- Email: [email protected]
Associations of the IL-1B level, IL-1A and IL-1B gene polymorphisms and ankylosing spondylitis risk in a Chinese Han population
Cytokine 126 (2020) 154918
Contents lists available at ScienceDirect
Cytokine journal homepage: www.elsevier.com/locate/cytokine
Associations of the IL-1B level, IL-1A and IL-1B gene polymorphisms and ankylosing spondylitis risk in a Chinese Han population Weixi Liub, Zhicheng Yanga, Ting Yana, Hui Zhanga, Ruiping Liua, a b
T
⁎
Department of Orthopedics, The Affiliated Changzhou No. 2 People’s Hospital of Nanjing Medical University, Changzhou 213003, China Xuzhou Medical University, Xuzhou 221004, China
A R T I C LE I N FO
A B S T R A C T
Keywords: Ankylosing spondylitis Polymorphism IL-1A IL-1B
Introduction: The aim of this study was to investigate the effect of interleukin (IL)-1A and IL-1B gene polymorphisms on ankylosing spondylitis (AS) susceptibility in a Chinese population. Additionally, we examined the association of IL-1B level with different genotype of rs2853550 polymorphism and clinicopathological features of AS patients. Materials and methods: The IL-1B concentration in plasma was determined by an enzyme-linked immunosorbent assay. The IL-1A rs3783546, IL-1A rs3783550 and IL-1B rs2853550 gene polymorphisms were determined by using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. Results: Our data indicated that the average plasma IL-1B concentration in the AS patients was markedly higher than in the control samples. Subgroup analyses suggested that there was no significant association between plasma IL-1B concentration and sex, age, HLA-B27, C-reactive protein (CRP), or grade of the sacroiliac joint in AS patients. We also found that the IL-1B rs2853550 AG genotype showed significantly correlation with an increased risk of AS. In comparing AS patients to control participants, elevated plasma concentrations were observed in AS patients while significant differences were found between the IL-1B rs2853550 AA genotypes. There is a negative correlation between the IL-1A rs3783550 and IL-1A rs3783546 polymorphisms in the AS patients in relation to controls. Conclusions: The IL-1B concentration in plasma was markedly higher in cases and AA genotype carriers. Furthermore, IL-1B rs2853550 AG was a genetic contributor to AS risk in a Chinese population.
1. Introduction Ankylosing spondylitis (AS) is a chronic inflammatory disease, which primarily affects the axial skeleton, and causes spinal ankylosis [1,2]. Most AS patients have low back pain, high fracture rate, and weak labor, which causes huge economic burden on society [3]. However, the etiology of AS remains unclear. Genetic composition, immune response dysfunctions and infectious agents may contribute to the development of AS [4]. A twin study suggested that the development of AS is largely determined through genetic factors may account for the development of AS significantly [5]. Abnormal immune function often results in the release of inflammatory factors, which include interleukin (IL)-1, IL-6, and tumor necrosis factor (TNF)-α [6–8]. IL-1 is secreted by activated macrophages in inflamed synovium, and initiates the recruitment of immune cells. The IL-1 gene cluster trigger innate inflammation (an important feature of AS) and host
defense against infection [10]. The cluster contained three cytokines, IL-1A, IL-1B, and IL-1RN [9], but few studies throw lights on IL-1A and IL-1B. Increased production of IL-1B has been observed in patients with AS when compared to healthy controls [11]. A genome-wide association studies conducted by Timms revealed et al. that the IL-1 gene cluster contains a major susceptibility locus for ankylosing spondylitis [9]. IL-1 gene single nucleotide polymorphisms (SNPs) are linked to AS, exploring the biological effects of IL-1 gene cluster polymorphisms may lead to new understanding and diagnostic capacity for AS. Consequently, this may assist in the development of effective AS treatments [12]. A meta-analysis showed that the OR IL-1A +889 allele (rs1800587) increased the risk of AS patients in Europe (OR = 1.357, 95% CI = 1.085–1.697, P = 0.007), while no association between the IL-1B −511 and +3953 polymorphisms and AS was found in the same population [13]. In a family study, there is a strong correlation between
Abbreviations: IL-1A, interleukin 1A; IL-1B, interleukin 1B; AS, ankylosing spondylitis; OR, odds ratio; CI, confidence interval; SNP, single nucleotide polymorphism ⁎ Corresponding author. E-mail address: [email protected] (R. Liu). https://doi.org/10.1016/j.cyto.2019.154918 Received 11 June 2019; Received in revised form 16 October 2019; Accepted 31 October 2019 1043-4666/ © 2019 Elsevier Ltd. All rights reserved.
Cytokine 126 (2020) 154918
W. Liu, et al.
the IL-1A-associated rs2856836 SNP and risk of spondyloarthritis (P = 0.009) and AS (P = 0.010) [14]. They also found a significant association between AS and IL-1A by combining family and case-control studies (rs1894399, P = 0.024) [14]. Our group explored the potential association between the plasma IL1B expression levels and clinical parameters and susceptibility of AS patients in a Chinese Han population. We also examined the associations between the IL-1B rs2853550 genotype and plasma IL-1B values. Lastly, we assessed the correlation between the IL-1A rs3783546, IL-1A rs3783550 and IL-1B rs2853550 polymorphisms and AS susceptibility.
Table 1 Patient demographics and risk factors in ankylosing spondylitis. Variable*
Cases (n = 190)
Controls (n = 190)
P
Age (years) Male/female CRP positive, no. (%) HLA-B27 positive, no. (%) Grading of sacroiliac joint, no. (%) Grade I Grade II Grade III Grade IV IL-1B levels** (pg/mL)
32.49 ( ± 10.15) 142/48 118 (62.11%) 151 (79.47.25%)
33.38 ( ± 8.10) 140/50 — — —
0.345 0.815 — — —
0 (0.00%) 136 (71.58%) 31 (16.32%) 23 (12.11%) 205.46 ( ± 81.62)
— — — — 157.04 ( ± 113.81)
— — — — 0.002
2. Patients and methods 2.1. Participants
Bold values are statistically significant (P < 0.05). * CRP: C-reactive protein. ** IL-1B concentrations were available in 85 AS cases (AA: 69; AG: 16; GG: 0 of IL-1B rs2853550 A/G) and 85 controls (AA: 65; AG: 20; GG: 0 of IL-1B rs2853550 A/G), with age, P = 0.214; sex, P = 0.506 (cases vs. controls).
This study was approved by the Ethics Committee of Nanjing Medical University (Nanjing, China). All participants signed written informed written consent before taking part in the study. 190 AS patients were consecutively recruited from The Affiliated Changzhou No.2 People’s Hospital of Nanjing Medical University (Changzhou, China) and The Changzhou First Hospital (Changzhou, China), between September 2010 and January 2015. The diagnosis of AS was based on the American College of Rheumatology (Modified New York Criteria) [15]. 190 controls were traumatic patients without AS, matched AS for age ( ± 5 years) and sex, and recruited from the above hospitals during the same period. A pretested questionnaire was designed to obtain information of AS patients on demographic data and related risk factors. Consequently, 2 mL of peripheral blood was collected from participants, using tubes containing ethylenediamine tetra-acetic acid (EDTA). Genomic DNA was isolated from peripheral blood sample using the QIAamp DNA Blood Mini Kit (Qiagen, Hilden, Germany). Genotyping was measured by matrix-assisted laser desorption/ionization time-offlight mass spectrometry using the MassARRAY system (Sequenom, San Diego, CA, USA) as previously described [16]. The plasma concentration of IL-1B in 85 AS patients and 85 randomly selected controls was measured by using an enzyme-linked immunosorbent assay Kit (Boster, Wuhan, China). We conducted the data analysis following the manufacturer’s recommendations. We calculated the concentration of IL-1B through a standard curve.
Table 2 Logistic regression analysis of associations between IL-1A rs3783546 G/C, IL-1A rs3783550 G/T and IL-1B rs2853550 A/G polymorphisms and risk of ankylosing spondylitis. Genotype
Cases* (n = 190)
Controls (n = 190)
OR (95% CI)
P
n
%
n
%
IL-1A rs3783546 GG GC (GC vs. GG) CC (CC vs. GG) GC + CC vs. GG CC vs. GC + GG C vs. G
94 78 17 — — —
49.74 41.27 8.99 — — —
87 77 24 — — —
46.27 40.96 12.77 — — —
1.00 1.43 1.53 1.15 1.48 1.18
(0.71–2.87) (0.77–3.03) (0.77–1.72) (0.77–2.86) (0.87–1.61)
— 0.314 0.228 0.502 0.242 0.285
IL-1A rs3783550 GG GT (GT vs. GG) TT (TT vs. GG) GT + TT vs. GG TT vs. GT + GG T vs. G
94 78 17 — — —
49.74 41.27 8.99 — — —
87 76 24 — — —
46.52 40.64 12.84 — — —
1.00 1.45 1.53 1.14 1.49 1.18
(0.72–2.91) (0.77–3.03) (0.76–1.71) (0.77–2.87) (0.87–1.60)
— 0.297 0.228 0.533 0.235 0.298
IL-1B rs2853550 AA AG (AG vs. AA) GG (GG vs. AA) AG + GG vs. AA GG vs. AG + AA G vs. A
161 28 0 — — —
85.19 14.81 0 — — —
136 52 0 — — —
72.34 27.66 0 — — —
1.00 2.20 (1.32–3.76) NA 2.20 (1.32–3.76) NA 0.92 (0.56–1.52)
2.2. Statistical analyses — 0.003 NA 0.003 NA 0.751
Differences in demographics, categorical variables, and genotypes of IL-1A rs3783546, IL-1A rs3783550 and IL-1B rs2853550 polymorphism variants were investigated by a chi-squared test. The associations between IL-1A rs3783546, IL-1A rs3783550 and IL-1B rs2853550 polymorphisms and AS risk were evaluated by calculating crude odds ratios (ORs) and 95% confidence intervals (CIs) using logistic regression analyses. The Hardy-Weinberg equilibrium (HWE) was tested by a goodness-of-fit chi-squared test to evaluate the deviation of genotype distributions among controls. The plasma IL-IB concentrations of different genotypes were explored by the Student’s t-test. All statistical analyses were carried out by SAS software (version 9.1.3; SAS Institute, Cary, NC, USA).
Bold values are statistically significant (P < 0.05). * The genotyping was successful in: 189 cases and 188 controls for IL-1B rs2853550 A/G and IL-1A rs3783546 G/C; 189 cases and 187 controls for IL-1A rs3783550 G/T. Table 3 The relationship between the single nucleotide polymorphisms in the human IL1B rs2853550 A/G and production of IL-1B. Genotype (case/control)
IL-1B Production (pg/mL)*
P value
3. Results AA (69/65) AG (16/20) GG (0/0) AA + AG + GG
Case (n = 85)
Control (n = 85)
205.89 ± 89.26 203.58 ± 34.35 NA 205.46 ( ± 81.62)
154.73 ± 118.21 164.53 ± 100.61 NA 157.04 ( ± 113.81)
3.1. Characteristics of the study population
0.005 0.118 NA 0.002
The demographic and clinical characteristics of participants are provided in Table 1. Subjects were adequately matched for age and sex (P = 0.345 and 0.815, respectively). The genotype and allelic distributions of IL-1A, IL-IB are summarized in Table 2. No significant deviation from HWE was observed for IL-1A rs3783546, IL-1A rs3783550 and IL-1B rs2853550 respectively.
HWE in controls for IL-1B rs2853550 A/G: P = 0.219. Bold values are statistically significant (P < 0.05). * Mean ± standard deviation. 2
Cytokine 126 (2020) 154918
W. Liu, et al.
Fig. 1. Association between IL-1B levels and IL-1B rs2853550 A/G genotype frequencies in ankylosing spondylitis (AS) or control group. Table 4 Stratification of association between plasma concentration of IL-1B and clinic biomarkers in AS patients. Variable
Case, n
Mean ± Std. Deviation (pg/mL)
P
Table 5 Logistic regression analysis of associations between IL-1B rs2853550 A/G polymorphisms and risk of grading of sacroiliac joint of patients with ankylosing spondylitis. Cases of grading of sacroiliac joint I + II (n = 135)
Cases of grading of sacroiliac joint III + IV (n = 54)
OR (95% CI)
P
IL-1B rs2853550 AA AG (AG vs. AA)
112 23
49 5
— 0.181
GG (GG vs. AA) AG + GG vs. AA
0 23
0 5
GG vs. AG + AA A allele G allele (G vs. A)
0 247 23
0 103 5
1.00 2.01 (0.72–5.60) NA 2.01 (0.72–5.60) NA 1.00 1.92 (0.71–5.18)
Genotype
Age
≥30Ys < 30Ys
54 31
205.70 ± 85.42 205.32 ± 80.17
0.984
Sex
Male Female
61 24
209.22 ± 90.30 195.89 ± 54.10
0.501
HLA-B27
Negative Positive
24 61
229.80 ± 122.22 195.88 ± 57.19
0.203
CRP status
Negative Positive
35 50
197.78 ± 55.95 210.83 ± 95.79
0.471
Grading of sacroiliac joint
I + II III + IV
58 27
197.07 ± 63.60 223.48 ± 110.27
0.166
Bold values are statistically significant (P < 0.05).
NA 0.181 NA — 0.199
3.2. IL-1A/IL-1B SNPs and AS susceptibility
The genotyping was successful in 189 for IL-1B rs2853550 A/G.
IL-1B rs2853550 polymorphism was associated with the increased risk of AS (Table 2). AG genotype had a significantly elevated risk of AS compared with AA genotype (OR = 2.20, 95% CI: 1.32–3.76; P = 0.003). It also showed that there had no significant associations between IL-1A rs3783546, IL-1A rs3783550 polymorphisms and risk of AS patients (Table 2).
significantly among two groups (Fig. 1). There is no significant association between plasma concentration of IL-1B and sex, age, HLA-B27, CRP, or grade of the sacroiliac joint in AS patients (Table 4).
3.3. IL-1B expression levels in participants and different genotypes
Further, we explored the effect of the genotype distributions of rs2853550 polymorphism on the AS grading of sacroiliac joint. No significant interaction was observed under the five models (Table 5).
3.4. IL-1B rs2853550 polymorphism and AS grading of sacroiliac joint
The higher plasma concentration of IL-1B was observed in AS patients (Table 1). The IL-1B plasma concentration was compared according to IL-1B rs2853550 genotypes. We found IL-1B rs2853550 AA genotype had significant higher concentration of IL-1B in case group when compared with control groups (Table 3). The IL-1B plasma concentrations of different IL-1B rs2853550 genotypes did not differ
3.5. Meta-analysis of IL-1B rs2853550 polymorphism Two studies (including this study) throw light on the association of IL-1B rs2853550 polymorphism with AS risk [17]. In order to better 3
Cytokine 126 (2020) 154918
W. Liu, et al.
Table 6 Meta-analysis of the associations between IL-1B rs2853550 A/G polymorphisms and AS risk. SNP
Comparison
Category
Category
OR (95% CI)
P-value
P for heterogeneity
IL-1B rs2853550
AG vs. AA
Total 2019 2017
This study Li et al. [17]
1.44 (0.64, 3.27) 2.20 (1.32, 3.76) 0.96 (0.59, 1.56)
0.379 0.003 0.853
0.021 – –
Total 2019 2017
This study Li et al. [17]
1.13(0.30, 4.26) NA 1.13 (0.30, 4.26)
0.856 NA 0.856
NA – –
Total 2019 2017
This study Li et al. [17]
1.45 (0.65, 3.23) 2.20 (1.32, 3.76) 0.97 (0.61, 1.55)
0.361 0.003 0.906
0.021 – –
Total 2019 2017
This study Li et al. [17]
1.14 (0.30, 4.28) NA 1.14(0.30, 4.28)
0.849 NA 0.849
NA – –
Total 2019 2017
This study Li et al. [17]
0.71(0.44, 1.16) 0.92(0.56, 1.52) 0.56(0.35, 0.89)
0.174 0.751 0.013
0.148 – –
GG vs. AA
GG + AG vs. AA
GG vs. AG + AA
G vs. A
Bold values are statistically significant of total values (P < 0.05).
developing AS, the IL-1B rs2853550 AG genotype of rs2853550 did. However, following the collation of our results with those generated by Li et al. (2017), IL-1B rs2853550 exhibited negative association with AS risk (Table 6). We searched Ensembl (http://grch37.ensembl.org/index.html) and found that rs2856836 A/G located in Chromosome 2:113587121 (forward strand), and was a binding site for transcription factors. So, SNP of rs2856836 A/G may exert its biological function by influencing the binding transcription factors. The positive findings need to be interpreted with caution due to several limitations. First, the control group was selected from trauma patients receiving surgery in the above hospitals, which led to an unavoidable selection bias. Second, further fine-mapping studies are required based on their functional characteristics. Third, despite collating our study population with results generated by Li et al. (2017), the sample size of this study was relatively small. We could not rule out the possibility of false-positive or false-negative results. Fourth, we would conduct the relevant experiment to investigate the association of different genotype and drug sensitivity of AS patients. Consequently, studies including larger, more ethnic populations are necessary to confirm these findings.
understand the genetic risk of IL-1B in the relationship with AS, we performed this meta-analysis to illuminate this association and determine whether the rs2853550 polymorphisms of IL-1B conferred susceptibility to AS. Our results revealed that this SNP was not associated with the risk of AS in the overall population under the five models. 4. Discussion We examined the associations between the IL-1A rs3783546, IL-1A rs3783550 and IL-1B rs2853550 polymorphisms and the risk of AS in a Chinese Han population. IL-1B rs2853550 AG was associated with an increased risk of AS. The average concentration of IL-1B in plasma was significantly higher in AS patients compared to controls, and that the homozygous AA, but not the heterozygote AG genotype, in AS patients possessed significantly higher concentrations of IL-1B. In our study, we found that there were no significant relationship between the IL-1Aassociated rs3783546 and rs3783550 polymorphisms and the risk of AS. IL-1 was involved in the pathogenesis of chronic inflammatory disorders of AS [14], with studies conducted on IL-1 indicating that it is a potential treatment target in patients with AS [18]. The average plasma levels of IL-1B in AS cases is controversial when compared to healthy controls. While one study proved that IL-1B levels were higher in patients with AS (median 242 pg/mL) than in controls (median 65 pg/mL; P = 0.002) [11], a separate study showed that higher IL-6 and TNF-α serum levels, but not IL-1B, were observed in AS patients than in cases with non-inflammatory back pain [19]. In our study, IL-1B concentrations were higher in AS individuals (median 205.46 pg/mL) when compared to control samples (median 157.04 pg/mL; P = 0.002). Stratification analysis indicated that the homozygote AA IL-1B rs2853550, but not heterozygote AG genotype, possessed significantly higher levels of IL-1B (AS median 205.89 pg/mL; control median 154.73 pg/mL; P = 0.005). Genetic factors contributed to the development of AS greatly [5], and many researchers have conducted studies on IL-1 SNPs across AS and healthy control. Li et al. (2017) conducted a study on the association between IL-1A and IL-1B polymorphisms with AS in a Chinese Han population. They found that the “T” genotype of IL-1A rs3783550 or “C” genotype of IL-1A rs3783546 was associated with decreased AS risk in the dominant (P = 0.044) and log-additive models. Furthermore, the minor allele “A” of rs2853550 may correlated with the reduced risk of AS under the dominant (P = 0.025) and log-additive models (P = 0.024) [17]. In this study, although the presence of IL-1A rs3783546 and IL-1A rs3783550 did not correlate to a risk of
Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper. Acknowledgements This study was supported in part by Changzhou High-Level Medical Talents Training Project (2016CZLJ011). References [1] J. Braun, J. Sieper, Ankylosing spondylitis, Lancet 369 (2007) 1379–1390, https:// doi.org/10.1016/S0140-6736(07)60635-7. [2] A.S. Rolle, B. Zimmermann, S.H. Poon, Etanercept-induced Henoch-Schonlein purpura in a patient with ankylosing spondylitis, J. Clin. Rheumatol. 19 (2013) 90–93, https://doi.org/10.1097/RHU.0b013e3182863027. [3] A. Boonen, S.M. van der Linden, The burden of ankylosing spondylitis, J. Rheumatol. Suppl. 78 (2006) 4–11. [4] Z. Li, S. Akar, H. Yarkan, S.K. Lee, P. Cetin, G. Can, G. Kenar, F. Capa, O.N. Pamuk, Y. Pehlivan, K. Cremin, E. De Guzman, J. Harris, L. Wheeler, A. Jamshidi, M. Vojdanian, E. Farhadi, N. Ahmadzadeh, Z. Yuce, E. Dalkilic, D. Solmaz, B. Akin, S. Donmez, I. Sari, P.J. Leo, T.J. Kenna, F. Onen, M. Mahmoudi, M.A. Brown, N. Akkoc, Genome-wide association study in Turkish and Iranian populations identify rare familial Mediterranean fever gene (MEFV) polymorphisms associated
4
Cytokine 126 (2020) 154918
W. Liu, et al.
[5]
[6]
[7]
[8]
[9]
[10]
[11]
with ankylosing spondylitis, PLoS Genet. 15 (2019) e1008038, https://doi.org/10. 1371/journal.pgen.1008038. M.A. Brown, L.G. Kennedy, A.J. MacGregor, C. Darke, E. Duncan, J.L. Shatford, A. Taylor, A. Calin, P. Wordsworth, Susceptibility to ankylosing spondylitis in twins: the role of genes, HLA, and the environment, Arthrit. Rheumat. 40 (1997) 1823–1828, https://doi.org/10.1002/1529-0131(199710)40:10<1823::AIDART15>3.0.CO;2-1. M. Schulz, H. Dotzlaw, G. Neeck, Ankylosing spondylitis and rheumatoid arthritis: serum levels of TNF-alpha and its soluble receptors during the course of therapy with etanercept and infliximab, BioMed Res. Int. 2014 (2014) 675108, https://doi. org/10.1155/2014/675108. A. Bal, E. Unlu, G. Bahar, E. Aydog, E. Eksioglu, R. Yorgancioglu, Comparison of serum IL-1 beta, sIL-2R, IL-6, and TNF-alpha levels with disease activity parameters in ankylosing spondylitis, Clin. Rheumatol. 26 (2007) 211–215, https://doi.org/10. 1007/s10067-006-0283-5. B. Chen, K. Huang, L. Ye, Y. Li, J. Zhang, J. Zhang, X. Fan, X. Liu, L. Li, J. Sun, J. Du, Z. Huang, Interleukin-37 is increased in ankylosing spondylitis patients and associated with disease activity, J. Transl. Med. 13 (2015) 36, https://doi.org/10.1186/ s12967-015-0394-3. A.E. Timms, A.M. Crane, A.M. Sims, H.J. Cordell, L.A. Bradbury, A. Abbott, M.R. Coyne, O. Beynon, I. Herzberg, G.W. Duff, A. Calin, L.R. Cardon, B.P. Wordsworth, M.A. Brown, The interleukin 1 gene cluster contains a major susceptibility locus for ankylosing spondylitis, Am. J. Hum. Genet. 75 (2004) 587–595, https://doi.org/10.1086/424695. P. Das, S. Barua, S. Sarkar, N. Karak, P. Bhattacharyya, N. Raza, K.H. Kim, S.S. Bhattacharya, Plant extract-mediated green silver nanoparticles: efficacy as soil conditioner and plant growth promoter, J. Hazard. Mater. 346 (2018) 62–72, https://doi.org/10.1016/j.jhazmat.2017.12.020. M. Vazquez-Del Mercado, A. Garcia-Gonzalez, J.F. Munoz-Valle, T. Garcia-Iglesias, G. Martinez-Bonilla, G. Bernard-Medina, A. Sanchez-Ortiz, J.M. Ornelas-Aguirre, M. Salazar-Paramo, J.I. Gamez-Nava, L. Gonzalez-Lopez, Interleukin 1beta (IL-
[12]
[13]
[14]
[15]
[16]
[17]
[18]
[19]
5
1beta), IL-10, tumor necrosis factor-alpha, and cellular proliferation index in peripheral blood mononuclear cells in patients with ankylosing spondylitis, J. Rheumatol. 29 (2002) 522–526. K. Khazim, E.E. Azulay, B. Kristal, I. Cohen, Interleukin 1 gene polymorphism and susceptibility to disease, Immunol. Rev. 281 (2018) 40–56, https://doi.org/10. 1111/imr.12620. W.I. Lea, Y.H. Lee, The associations between interleukin-1 polymorphisms and susceptibility to ankylosing spondylitis: a meta-analysis, Joint, Bone, Spine: revue du rhumatisme 79 (2012) 370–374, https://doi.org/10.1016/j.jbspin.2011.06.010. D. Monnet, A. Kadi, B. Izac, N. Lebrun, F. Letourneur, E. Zinovieva, R. Said-Nahal, G. Chiocchia, M. Breban, Association between the IL-1 family gene cluster and spondyloarthritis, Ann. Rheumat. Dis. 71 (2012) 885–890, https://doi.org/10. 1136/annrheumdis-2011-200439. S. van der Linden, H.A. Valkenburg, A. Cats, Evaluation of diagnostic criteria for ankylosing spondylitis.A proposal for modification of the New York criteria, Arthrit. Rheumat. 27 (1984) 361–368. Y. Huang, Y. Liu, L. Jiang, R. Sun, H. Zhang, R. Liu, N. Xu, Apolipoprotein m (APOM) levels and APOM rs805297 G/T polymorphism are associated with increased risk of rheumatoid arthritis, Joint, Bone, Spine: revue du rhumatisme 81 (2014) 32–36, https://doi.org/10.1016/j.jbspin.2013.03.017. L. Li, B. Shi, W. Zheng, W. Xing, Y. Zhao, F. Li, D. Xin, T. Jin, Y. Zhu, X. Yang, Association of IL-1A and IL-1B polymorphisms with ankylosing spondylitis among the Chinese Han population: a case-control study, Oncotarget 8 (2017) 28278–28284, https://doi.org/10.18632/oncotarget.16004. D. Wendling, Interleukin-1: a new therapeutic target for ankylosing spondylitis? Joint, Bone, Spine: revue du rhumatisme 72 (2005) 357–358, https://doi.org/10. 1016/j.jbspin.2004.10.013. J. Gratacos, A. Collado, X. Filella, R. Sanmarti, J. Canete, J. Llena, R. Molina, A. Ballesta, J. Munoz-Gomez, Serum cytokines (IL-6, TNF-alpha, IL-1 beta and IFNgamma) in ankylosing spondylitis: a close correlation between serum IL-6 and disease activity and severity, Br. J. Rheumatol. 33 (1994) 927–931.
Contents lists available at ScienceDirect
Cytokine journal homepage: www.elsevier.com/locate/cytokine
Associations of the IL-1B level, IL-1A and IL-1B gene polymorphisms and ankylosing spondylitis risk in a Chinese Han population Weixi Liub, Zhicheng Yanga, Ting Yana, Hui Zhanga, Ruiping Liua, a b
T
⁎
Department of Orthopedics, The Affiliated Changzhou No. 2 People’s Hospital of Nanjing Medical University, Changzhou 213003, China Xuzhou Medical University, Xuzhou 221004, China
A R T I C LE I N FO
A B S T R A C T
Keywords: Ankylosing spondylitis Polymorphism IL-1A IL-1B
Introduction: The aim of this study was to investigate the effect of interleukin (IL)-1A and IL-1B gene polymorphisms on ankylosing spondylitis (AS) susceptibility in a Chinese population. Additionally, we examined the association of IL-1B level with different genotype of rs2853550 polymorphism and clinicopathological features of AS patients. Materials and methods: The IL-1B concentration in plasma was determined by an enzyme-linked immunosorbent assay. The IL-1A rs3783546, IL-1A rs3783550 and IL-1B rs2853550 gene polymorphisms were determined by using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. Results: Our data indicated that the average plasma IL-1B concentration in the AS patients was markedly higher than in the control samples. Subgroup analyses suggested that there was no significant association between plasma IL-1B concentration and sex, age, HLA-B27, C-reactive protein (CRP), or grade of the sacroiliac joint in AS patients. We also found that the IL-1B rs2853550 AG genotype showed significantly correlation with an increased risk of AS. In comparing AS patients to control participants, elevated plasma concentrations were observed in AS patients while significant differences were found between the IL-1B rs2853550 AA genotypes. There is a negative correlation between the IL-1A rs3783550 and IL-1A rs3783546 polymorphisms in the AS patients in relation to controls. Conclusions: The IL-1B concentration in plasma was markedly higher in cases and AA genotype carriers. Furthermore, IL-1B rs2853550 AG was a genetic contributor to AS risk in a Chinese population.
1. Introduction Ankylosing spondylitis (AS) is a chronic inflammatory disease, which primarily affects the axial skeleton, and causes spinal ankylosis [1,2]. Most AS patients have low back pain, high fracture rate, and weak labor, which causes huge economic burden on society [3]. However, the etiology of AS remains unclear. Genetic composition, immune response dysfunctions and infectious agents may contribute to the development of AS [4]. A twin study suggested that the development of AS is largely determined through genetic factors may account for the development of AS significantly [5]. Abnormal immune function often results in the release of inflammatory factors, which include interleukin (IL)-1, IL-6, and tumor necrosis factor (TNF)-α [6–8]. IL-1 is secreted by activated macrophages in inflamed synovium, and initiates the recruitment of immune cells. The IL-1 gene cluster trigger innate inflammation (an important feature of AS) and host
defense against infection [10]. The cluster contained three cytokines, IL-1A, IL-1B, and IL-1RN [9], but few studies throw lights on IL-1A and IL-1B. Increased production of IL-1B has been observed in patients with AS when compared to healthy controls [11]. A genome-wide association studies conducted by Timms revealed et al. that the IL-1 gene cluster contains a major susceptibility locus for ankylosing spondylitis [9]. IL-1 gene single nucleotide polymorphisms (SNPs) are linked to AS, exploring the biological effects of IL-1 gene cluster polymorphisms may lead to new understanding and diagnostic capacity for AS. Consequently, this may assist in the development of effective AS treatments [12]. A meta-analysis showed that the OR IL-1A +889 allele (rs1800587) increased the risk of AS patients in Europe (OR = 1.357, 95% CI = 1.085–1.697, P = 0.007), while no association between the IL-1B −511 and +3953 polymorphisms and AS was found in the same population [13]. In a family study, there is a strong correlation between
Abbreviations: IL-1A, interleukin 1A; IL-1B, interleukin 1B; AS, ankylosing spondylitis; OR, odds ratio; CI, confidence interval; SNP, single nucleotide polymorphism ⁎ Corresponding author. E-mail address: [email protected] (R. Liu). https://doi.org/10.1016/j.cyto.2019.154918 Received 11 June 2019; Received in revised form 16 October 2019; Accepted 31 October 2019 1043-4666/ © 2019 Elsevier Ltd. All rights reserved.
Cytokine 126 (2020) 154918
W. Liu, et al.
the IL-1A-associated rs2856836 SNP and risk of spondyloarthritis (P = 0.009) and AS (P = 0.010) [14]. They also found a significant association between AS and IL-1A by combining family and case-control studies (rs1894399, P = 0.024) [14]. Our group explored the potential association between the plasma IL1B expression levels and clinical parameters and susceptibility of AS patients in a Chinese Han population. We also examined the associations between the IL-1B rs2853550 genotype and plasma IL-1B values. Lastly, we assessed the correlation between the IL-1A rs3783546, IL-1A rs3783550 and IL-1B rs2853550 polymorphisms and AS susceptibility.
Table 1 Patient demographics and risk factors in ankylosing spondylitis. Variable*
Cases (n = 190)
Controls (n = 190)
P
Age (years) Male/female CRP positive, no. (%) HLA-B27 positive, no. (%) Grading of sacroiliac joint, no. (%) Grade I Grade II Grade III Grade IV IL-1B levels** (pg/mL)
32.49 ( ± 10.15) 142/48 118 (62.11%) 151 (79.47.25%)
33.38 ( ± 8.10) 140/50 — — —
0.345 0.815 — — —
0 (0.00%) 136 (71.58%) 31 (16.32%) 23 (12.11%) 205.46 ( ± 81.62)
— — — — 157.04 ( ± 113.81)
— — — — 0.002
2. Patients and methods 2.1. Participants
Bold values are statistically significant (P < 0.05). * CRP: C-reactive protein. ** IL-1B concentrations were available in 85 AS cases (AA: 69; AG: 16; GG: 0 of IL-1B rs2853550 A/G) and 85 controls (AA: 65; AG: 20; GG: 0 of IL-1B rs2853550 A/G), with age, P = 0.214; sex, P = 0.506 (cases vs. controls).
This study was approved by the Ethics Committee of Nanjing Medical University (Nanjing, China). All participants signed written informed written consent before taking part in the study. 190 AS patients were consecutively recruited from The Affiliated Changzhou No.2 People’s Hospital of Nanjing Medical University (Changzhou, China) and The Changzhou First Hospital (Changzhou, China), between September 2010 and January 2015. The diagnosis of AS was based on the American College of Rheumatology (Modified New York Criteria) [15]. 190 controls were traumatic patients without AS, matched AS for age ( ± 5 years) and sex, and recruited from the above hospitals during the same period. A pretested questionnaire was designed to obtain information of AS patients on demographic data and related risk factors. Consequently, 2 mL of peripheral blood was collected from participants, using tubes containing ethylenediamine tetra-acetic acid (EDTA). Genomic DNA was isolated from peripheral blood sample using the QIAamp DNA Blood Mini Kit (Qiagen, Hilden, Germany). Genotyping was measured by matrix-assisted laser desorption/ionization time-offlight mass spectrometry using the MassARRAY system (Sequenom, San Diego, CA, USA) as previously described [16]. The plasma concentration of IL-1B in 85 AS patients and 85 randomly selected controls was measured by using an enzyme-linked immunosorbent assay Kit (Boster, Wuhan, China). We conducted the data analysis following the manufacturer’s recommendations. We calculated the concentration of IL-1B through a standard curve.
Table 2 Logistic regression analysis of associations between IL-1A rs3783546 G/C, IL-1A rs3783550 G/T and IL-1B rs2853550 A/G polymorphisms and risk of ankylosing spondylitis. Genotype
Cases* (n = 190)
Controls (n = 190)
OR (95% CI)
P
n
%
n
%
IL-1A rs3783546 GG GC (GC vs. GG) CC (CC vs. GG) GC + CC vs. GG CC vs. GC + GG C vs. G
94 78 17 — — —
49.74 41.27 8.99 — — —
87 77 24 — — —
46.27 40.96 12.77 — — —
1.00 1.43 1.53 1.15 1.48 1.18
(0.71–2.87) (0.77–3.03) (0.77–1.72) (0.77–2.86) (0.87–1.61)
— 0.314 0.228 0.502 0.242 0.285
IL-1A rs3783550 GG GT (GT vs. GG) TT (TT vs. GG) GT + TT vs. GG TT vs. GT + GG T vs. G
94 78 17 — — —
49.74 41.27 8.99 — — —
87 76 24 — — —
46.52 40.64 12.84 — — —
1.00 1.45 1.53 1.14 1.49 1.18
(0.72–2.91) (0.77–3.03) (0.76–1.71) (0.77–2.87) (0.87–1.60)
— 0.297 0.228 0.533 0.235 0.298
IL-1B rs2853550 AA AG (AG vs. AA) GG (GG vs. AA) AG + GG vs. AA GG vs. AG + AA G vs. A
161 28 0 — — —
85.19 14.81 0 — — —
136 52 0 — — —
72.34 27.66 0 — — —
1.00 2.20 (1.32–3.76) NA 2.20 (1.32–3.76) NA 0.92 (0.56–1.52)
2.2. Statistical analyses — 0.003 NA 0.003 NA 0.751
Differences in demographics, categorical variables, and genotypes of IL-1A rs3783546, IL-1A rs3783550 and IL-1B rs2853550 polymorphism variants were investigated by a chi-squared test. The associations between IL-1A rs3783546, IL-1A rs3783550 and IL-1B rs2853550 polymorphisms and AS risk were evaluated by calculating crude odds ratios (ORs) and 95% confidence intervals (CIs) using logistic regression analyses. The Hardy-Weinberg equilibrium (HWE) was tested by a goodness-of-fit chi-squared test to evaluate the deviation of genotype distributions among controls. The plasma IL-IB concentrations of different genotypes were explored by the Student’s t-test. All statistical analyses were carried out by SAS software (version 9.1.3; SAS Institute, Cary, NC, USA).
Bold values are statistically significant (P < 0.05). * The genotyping was successful in: 189 cases and 188 controls for IL-1B rs2853550 A/G and IL-1A rs3783546 G/C; 189 cases and 187 controls for IL-1A rs3783550 G/T. Table 3 The relationship between the single nucleotide polymorphisms in the human IL1B rs2853550 A/G and production of IL-1B. Genotype (case/control)
IL-1B Production (pg/mL)*
P value
3. Results AA (69/65) AG (16/20) GG (0/0) AA + AG + GG
Case (n = 85)
Control (n = 85)
205.89 ± 89.26 203.58 ± 34.35 NA 205.46 ( ± 81.62)
154.73 ± 118.21 164.53 ± 100.61 NA 157.04 ( ± 113.81)
3.1. Characteristics of the study population
0.005 0.118 NA 0.002
The demographic and clinical characteristics of participants are provided in Table 1. Subjects were adequately matched for age and sex (P = 0.345 and 0.815, respectively). The genotype and allelic distributions of IL-1A, IL-IB are summarized in Table 2. No significant deviation from HWE was observed for IL-1A rs3783546, IL-1A rs3783550 and IL-1B rs2853550 respectively.
HWE in controls for IL-1B rs2853550 A/G: P = 0.219. Bold values are statistically significant (P < 0.05). * Mean ± standard deviation. 2
Cytokine 126 (2020) 154918
W. Liu, et al.
Fig. 1. Association between IL-1B levels and IL-1B rs2853550 A/G genotype frequencies in ankylosing spondylitis (AS) or control group. Table 4 Stratification of association between plasma concentration of IL-1B and clinic biomarkers in AS patients. Variable
Case, n
Mean ± Std. Deviation (pg/mL)
P
Table 5 Logistic regression analysis of associations between IL-1B rs2853550 A/G polymorphisms and risk of grading of sacroiliac joint of patients with ankylosing spondylitis. Cases of grading of sacroiliac joint I + II (n = 135)
Cases of grading of sacroiliac joint III + IV (n = 54)
OR (95% CI)
P
IL-1B rs2853550 AA AG (AG vs. AA)
112 23
49 5
— 0.181
GG (GG vs. AA) AG + GG vs. AA
0 23
0 5
GG vs. AG + AA A allele G allele (G vs. A)
0 247 23
0 103 5
1.00 2.01 (0.72–5.60) NA 2.01 (0.72–5.60) NA 1.00 1.92 (0.71–5.18)
Genotype
Age
≥30Ys < 30Ys
54 31
205.70 ± 85.42 205.32 ± 80.17
0.984
Sex
Male Female
61 24
209.22 ± 90.30 195.89 ± 54.10
0.501
HLA-B27
Negative Positive
24 61
229.80 ± 122.22 195.88 ± 57.19
0.203
CRP status
Negative Positive
35 50
197.78 ± 55.95 210.83 ± 95.79
0.471
Grading of sacroiliac joint
I + II III + IV
58 27
197.07 ± 63.60 223.48 ± 110.27
0.166
Bold values are statistically significant (P < 0.05).
NA 0.181 NA — 0.199
3.2. IL-1A/IL-1B SNPs and AS susceptibility
The genotyping was successful in 189 for IL-1B rs2853550 A/G.
IL-1B rs2853550 polymorphism was associated with the increased risk of AS (Table 2). AG genotype had a significantly elevated risk of AS compared with AA genotype (OR = 2.20, 95% CI: 1.32–3.76; P = 0.003). It also showed that there had no significant associations between IL-1A rs3783546, IL-1A rs3783550 polymorphisms and risk of AS patients (Table 2).
significantly among two groups (Fig. 1). There is no significant association between plasma concentration of IL-1B and sex, age, HLA-B27, CRP, or grade of the sacroiliac joint in AS patients (Table 4).
3.3. IL-1B expression levels in participants and different genotypes
Further, we explored the effect of the genotype distributions of rs2853550 polymorphism on the AS grading of sacroiliac joint. No significant interaction was observed under the five models (Table 5).
3.4. IL-1B rs2853550 polymorphism and AS grading of sacroiliac joint
The higher plasma concentration of IL-1B was observed in AS patients (Table 1). The IL-1B plasma concentration was compared according to IL-1B rs2853550 genotypes. We found IL-1B rs2853550 AA genotype had significant higher concentration of IL-1B in case group when compared with control groups (Table 3). The IL-1B plasma concentrations of different IL-1B rs2853550 genotypes did not differ
3.5. Meta-analysis of IL-1B rs2853550 polymorphism Two studies (including this study) throw light on the association of IL-1B rs2853550 polymorphism with AS risk [17]. In order to better 3
Cytokine 126 (2020) 154918
W. Liu, et al.
Table 6 Meta-analysis of the associations between IL-1B rs2853550 A/G polymorphisms and AS risk. SNP
Comparison
Category
Category
OR (95% CI)
P-value
P for heterogeneity
IL-1B rs2853550
AG vs. AA
Total 2019 2017
This study Li et al. [17]
1.44 (0.64, 3.27) 2.20 (1.32, 3.76) 0.96 (0.59, 1.56)
0.379 0.003 0.853
0.021 – –
Total 2019 2017
This study Li et al. [17]
1.13(0.30, 4.26) NA 1.13 (0.30, 4.26)
0.856 NA 0.856
NA – –
Total 2019 2017
This study Li et al. [17]
1.45 (0.65, 3.23) 2.20 (1.32, 3.76) 0.97 (0.61, 1.55)
0.361 0.003 0.906
0.021 – –
Total 2019 2017
This study Li et al. [17]
1.14 (0.30, 4.28) NA 1.14(0.30, 4.28)
0.849 NA 0.849
NA – –
Total 2019 2017
This study Li et al. [17]
0.71(0.44, 1.16) 0.92(0.56, 1.52) 0.56(0.35, 0.89)
0.174 0.751 0.013
0.148 – –
GG vs. AA
GG + AG vs. AA
GG vs. AG + AA
G vs. A
Bold values are statistically significant of total values (P < 0.05).
developing AS, the IL-1B rs2853550 AG genotype of rs2853550 did. However, following the collation of our results with those generated by Li et al. (2017), IL-1B rs2853550 exhibited negative association with AS risk (Table 6). We searched Ensembl (http://grch37.ensembl.org/index.html) and found that rs2856836 A/G located in Chromosome 2:113587121 (forward strand), and was a binding site for transcription factors. So, SNP of rs2856836 A/G may exert its biological function by influencing the binding transcription factors. The positive findings need to be interpreted with caution due to several limitations. First, the control group was selected from trauma patients receiving surgery in the above hospitals, which led to an unavoidable selection bias. Second, further fine-mapping studies are required based on their functional characteristics. Third, despite collating our study population with results generated by Li et al. (2017), the sample size of this study was relatively small. We could not rule out the possibility of false-positive or false-negative results. Fourth, we would conduct the relevant experiment to investigate the association of different genotype and drug sensitivity of AS patients. Consequently, studies including larger, more ethnic populations are necessary to confirm these findings.
understand the genetic risk of IL-1B in the relationship with AS, we performed this meta-analysis to illuminate this association and determine whether the rs2853550 polymorphisms of IL-1B conferred susceptibility to AS. Our results revealed that this SNP was not associated with the risk of AS in the overall population under the five models. 4. Discussion We examined the associations between the IL-1A rs3783546, IL-1A rs3783550 and IL-1B rs2853550 polymorphisms and the risk of AS in a Chinese Han population. IL-1B rs2853550 AG was associated with an increased risk of AS. The average concentration of IL-1B in plasma was significantly higher in AS patients compared to controls, and that the homozygous AA, but not the heterozygote AG genotype, in AS patients possessed significantly higher concentrations of IL-1B. In our study, we found that there were no significant relationship between the IL-1Aassociated rs3783546 and rs3783550 polymorphisms and the risk of AS. IL-1 was involved in the pathogenesis of chronic inflammatory disorders of AS [14], with studies conducted on IL-1 indicating that it is a potential treatment target in patients with AS [18]. The average plasma levels of IL-1B in AS cases is controversial when compared to healthy controls. While one study proved that IL-1B levels were higher in patients with AS (median 242 pg/mL) than in controls (median 65 pg/mL; P = 0.002) [11], a separate study showed that higher IL-6 and TNF-α serum levels, but not IL-1B, were observed in AS patients than in cases with non-inflammatory back pain [19]. In our study, IL-1B concentrations were higher in AS individuals (median 205.46 pg/mL) when compared to control samples (median 157.04 pg/mL; P = 0.002). Stratification analysis indicated that the homozygote AA IL-1B rs2853550, but not heterozygote AG genotype, possessed significantly higher levels of IL-1B (AS median 205.89 pg/mL; control median 154.73 pg/mL; P = 0.005). Genetic factors contributed to the development of AS greatly [5], and many researchers have conducted studies on IL-1 SNPs across AS and healthy control. Li et al. (2017) conducted a study on the association between IL-1A and IL-1B polymorphisms with AS in a Chinese Han population. They found that the “T” genotype of IL-1A rs3783550 or “C” genotype of IL-1A rs3783546 was associated with decreased AS risk in the dominant (P = 0.044) and log-additive models. Furthermore, the minor allele “A” of rs2853550 may correlated with the reduced risk of AS under the dominant (P = 0.025) and log-additive models (P = 0.024) [17]. In this study, although the presence of IL-1A rs3783546 and IL-1A rs3783550 did not correlate to a risk of
Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper. Acknowledgements This study was supported in part by Changzhou High-Level Medical Talents Training Project (2016CZLJ011). References [1] J. Braun, J. Sieper, Ankylosing spondylitis, Lancet 369 (2007) 1379–1390, https:// doi.org/10.1016/S0140-6736(07)60635-7. [2] A.S. Rolle, B. Zimmermann, S.H. Poon, Etanercept-induced Henoch-Schonlein purpura in a patient with ankylosing spondylitis, J. Clin. Rheumatol. 19 (2013) 90–93, https://doi.org/10.1097/RHU.0b013e3182863027. [3] A. Boonen, S.M. van der Linden, The burden of ankylosing spondylitis, J. Rheumatol. Suppl. 78 (2006) 4–11. [4] Z. Li, S. Akar, H. Yarkan, S.K. Lee, P. Cetin, G. Can, G. Kenar, F. Capa, O.N. Pamuk, Y. Pehlivan, K. Cremin, E. De Guzman, J. Harris, L. Wheeler, A. Jamshidi, M. Vojdanian, E. Farhadi, N. Ahmadzadeh, Z. Yuce, E. Dalkilic, D. Solmaz, B. Akin, S. Donmez, I. Sari, P.J. Leo, T.J. Kenna, F. Onen, M. Mahmoudi, M.A. Brown, N. Akkoc, Genome-wide association study in Turkish and Iranian populations identify rare familial Mediterranean fever gene (MEFV) polymorphisms associated
4
Cytokine 126 (2020) 154918
W. Liu, et al.
[5]
[6]
[7]
[8]
[9]
[10]
[11]
with ankylosing spondylitis, PLoS Genet. 15 (2019) e1008038, https://doi.org/10. 1371/journal.pgen.1008038. M.A. Brown, L.G. Kennedy, A.J. MacGregor, C. Darke, E. Duncan, J.L. Shatford, A. Taylor, A. Calin, P. Wordsworth, Susceptibility to ankylosing spondylitis in twins: the role of genes, HLA, and the environment, Arthrit. Rheumat. 40 (1997) 1823–1828, https://doi.org/10.1002/1529-0131(199710)40:10<1823::AIDART15>3.0.CO;2-1. M. Schulz, H. Dotzlaw, G. Neeck, Ankylosing spondylitis and rheumatoid arthritis: serum levels of TNF-alpha and its soluble receptors during the course of therapy with etanercept and infliximab, BioMed Res. Int. 2014 (2014) 675108, https://doi. org/10.1155/2014/675108. A. Bal, E. Unlu, G. Bahar, E. Aydog, E. Eksioglu, R. Yorgancioglu, Comparison of serum IL-1 beta, sIL-2R, IL-6, and TNF-alpha levels with disease activity parameters in ankylosing spondylitis, Clin. Rheumatol. 26 (2007) 211–215, https://doi.org/10. 1007/s10067-006-0283-5. B. Chen, K. Huang, L. Ye, Y. Li, J. Zhang, J. Zhang, X. Fan, X. Liu, L. Li, J. Sun, J. Du, Z. Huang, Interleukin-37 is increased in ankylosing spondylitis patients and associated with disease activity, J. Transl. Med. 13 (2015) 36, https://doi.org/10.1186/ s12967-015-0394-3. A.E. Timms, A.M. Crane, A.M. Sims, H.J. Cordell, L.A. Bradbury, A. Abbott, M.R. Coyne, O. Beynon, I. Herzberg, G.W. Duff, A. Calin, L.R. Cardon, B.P. Wordsworth, M.A. Brown, The interleukin 1 gene cluster contains a major susceptibility locus for ankylosing spondylitis, Am. J. Hum. Genet. 75 (2004) 587–595, https://doi.org/10.1086/424695. P. Das, S. Barua, S. Sarkar, N. Karak, P. Bhattacharyya, N. Raza, K.H. Kim, S.S. Bhattacharya, Plant extract-mediated green silver nanoparticles: efficacy as soil conditioner and plant growth promoter, J. Hazard. Mater. 346 (2018) 62–72, https://doi.org/10.1016/j.jhazmat.2017.12.020. M. Vazquez-Del Mercado, A. Garcia-Gonzalez, J.F. Munoz-Valle, T. Garcia-Iglesias, G. Martinez-Bonilla, G. Bernard-Medina, A. Sanchez-Ortiz, J.M. Ornelas-Aguirre, M. Salazar-Paramo, J.I. Gamez-Nava, L. Gonzalez-Lopez, Interleukin 1beta (IL-
[12]
[13]
[14]
[15]
[16]
[17]
[18]
[19]
5
1beta), IL-10, tumor necrosis factor-alpha, and cellular proliferation index in peripheral blood mononuclear cells in patients with ankylosing spondylitis, J. Rheumatol. 29 (2002) 522–526. K. Khazim, E.E. Azulay, B. Kristal, I. Cohen, Interleukin 1 gene polymorphism and susceptibility to disease, Immunol. Rev. 281 (2018) 40–56, https://doi.org/10. 1111/imr.12620. W.I. Lea, Y.H. Lee, The associations between interleukin-1 polymorphisms and susceptibility to ankylosing spondylitis: a meta-analysis, Joint, Bone, Spine: revue du rhumatisme 79 (2012) 370–374, https://doi.org/10.1016/j.jbspin.2011.06.010. D. Monnet, A. Kadi, B. Izac, N. Lebrun, F. Letourneur, E. Zinovieva, R. Said-Nahal, G. Chiocchia, M. Breban, Association between the IL-1 family gene cluster and spondyloarthritis, Ann. Rheumat. Dis. 71 (2012) 885–890, https://doi.org/10. 1136/annrheumdis-2011-200439. S. van der Linden, H.A. Valkenburg, A. Cats, Evaluation of diagnostic criteria for ankylosing spondylitis.A proposal for modification of the New York criteria, Arthrit. Rheumat. 27 (1984) 361–368. Y. Huang, Y. Liu, L. Jiang, R. Sun, H. Zhang, R. Liu, N. Xu, Apolipoprotein m (APOM) levels and APOM rs805297 G/T polymorphism are associated with increased risk of rheumatoid arthritis, Joint, Bone, Spine: revue du rhumatisme 81 (2014) 32–36, https://doi.org/10.1016/j.jbspin.2013.03.017. L. Li, B. Shi, W. Zheng, W. Xing, Y. Zhao, F. Li, D. Xin, T. Jin, Y. Zhu, X. Yang, Association of IL-1A and IL-1B polymorphisms with ankylosing spondylitis among the Chinese Han population: a case-control study, Oncotarget 8 (2017) 28278–28284, https://doi.org/10.18632/oncotarget.16004. D. Wendling, Interleukin-1: a new therapeutic target for ankylosing spondylitis? Joint, Bone, Spine: revue du rhumatisme 72 (2005) 357–358, https://doi.org/10. 1016/j.jbspin.2004.10.013. J. Gratacos, A. Collado, X. Filella, R. Sanmarti, J. Canete, J. Llena, R. Molina, A. Ballesta, J. Munoz-Gomez, Serum cytokines (IL-6, TNF-alpha, IL-1 beta and IFNgamma) in ankylosing spondylitis: a close correlation between serum IL-6 and disease activity and severity, Br. J. Rheumatol. 33 (1994) 927–931.