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T1220 Negative Feedback Regulation of Pathogenic CD4+ T Cells By Increased Granulopoiesis
T1219 Increased Expression of L-PGDS May Possibly Relate to Proinflammatory Roles in Colonic Mucosa of Ulcerative Colitis Patients Ryota Hokari, Hisayuki Matsunaga, Chikako Watanabe, Shunsuke Komoto, Masaaki Higashiyama, Mitsuyasu Nakamura, Chie Kurihara, Yoshikiyo Okada, Shigeaki Nagao, Atsushi Kawaguchi, Yoshikazu Tsuzuki, Soichiro Miura
T1217
Background The pathogenesis of ulcerative colitis (UC) is unclear, but enhancement of disease activity by usage of NSAIDs suggests involvement of prostanoid in its pathophysiology. Enhanced biosynthesis of prostaglandin (PG)D(2) has been suggested to contribute to inflammation in kidney or venular wall. Recently, PGD2 affects Th1/2 balance by stimulating Th2 cells via CRTH2 and suppressing Th1 cells via DP receptor In Vitro. However, the role of PGD2 in colonic mucosa is not studied at all. Thus we hypothesized that PGD2-CRTH2 may modulate colonic inflammation in UC. In this study we investigated the expression of enzymes for PGD2 synthesis and its relation to the activity of colitis. The role of L-PGDS using murine colitis model was also assessed. Methods Tissue samples were obtained by colonic biopsies from patients with UC or colonic polyps with informed consent. Th1/2 cell infiltration was studied immunohistochemically using antibody against CC chemokine receptor 5 (CCR5) and CRTH2. L-PGDS expression and Cox-2 expression were also investigated. Th1 related chemokine, MIP1-a and Th2 related enzymes, hematopoietic-type-prostaglandin D synthase (H-PGDS) and lipocalin-type-prostaglandin D synthase (L-PGDS) were studied by m-RNA expression using quantitative RT-PCR. C57Bl6 mice were treated with 3% dextran sodium sulfate drinking to induce colitis. Degree of inflammation was compared with L-PGDS -/- mice of the C57Bl6 background and control mice. Result CCR5 positive cells significantly increased in inflamed mucosa and it pararelled with disease activity. Mip1 alpha expression well co-related with CCR5. CRTH2 -positive cells was predominantly observed in the mildly inflamed or the margin of inflamed mucosa and decreased in severely active UC patients. mRNA expression of L-PGDS was increased in UC patients and it pararelled with disease activity. Co-localization of L-PGDS and Cox 2 were observed in mesenchymal cells in lamina propria in UC patients. On the contrary, H-PGDS did not differ from control mucosa. L-PGDS -/- mice showed lower disease activity than control mice. Conclusion: We first reported presence of L-PGD synthase in the Cox-2 + cells in UC patients and that only lipocalin type increased with disease activity. Infiltration of PGD2 receptor + cells also suggests PGD2 play some role in pathophysiology of UC. Animal model study suggests that PGD2 derived from L-PGDS + cells play proinflammatory role in UC.
A Novel Population of CD56+ HLA-DR+ Colonic Lamina Propria Cells Is Associated with Inflammation in Ulcerative Colitis Siew C. Ng, Sophie Plamondon, Hafid O. Al-Hassi, Nicholas R. English, Nichola L. Gellatly, Michael A. Kamm, Stella C. Knight, Andrew J. Stagg INTRODUCTION: The immunopathology of ulcerative colitis (UC) relates to an inappropriate mucosal immune response to constituents of the intestinal microbiota in genetically susceptible individuals. HLA-DR+ lin-/dim (lin = anti-CD3,14,16,19,34) cells extracted from human intestinal tissue contain CD11c+ myeloid dendritic cells (DC) that contribute to the immunoregulatory events that normally limit inflammatory responses to commensal bacteria. Also present within the HLA-DR+ lin-/dim population are hitherto poorly characterized CD11c- cells. We hypothesized that this population in the gut may also contribute to intestinal inflammation in active UC AIMS & METHODS: HLA-DR+ lin-/dim cells were identified in freshly isolated lamina propria mononuclear cells by multicolour flow cytometry, from patients with UC (n=48) and controls (n=22). The proportion and number of CD11c+ and CD11c- cells within this population were determined. Surface expression of the activation/maturation markers CD40, CD86, Toll-like receptors (TLR), TLR-2, TLR-4, and the natural killer cell marker, CD56 was assessed on each cell population. Morphology was assessed by electron microscopy and T cell stimulatory capacity measured in allogenic mixed leucocyte reaction (MLR). RESULTS: Lamina propria colonic HLA-DR+ lin-/dim cells, of the CD11c-, but not the CD11c+ subset, were significantly increased in inflamed tissue of patients with UC compared with control tissue (UC 447±94 versus Control 104±17 per mg; p<0.001). Numbers of CD11c- HLA-DR+ lin-/dim cells decreased after resolution of macroscopic inflammation. Nonetheless, CD11c- HLA-DR+ lin-/dim cells were significantly increased in non-inflamed tissue of UC patients compared with colonic tissue from healthy subjects (p<0.05). In UC, these CD11c- cells expressed CD40, CD86, TLR-2 and TLR-4 at lower levels than on their CD11c+ counterparts and were weakly stimulatory in an MLR. Few CD11c- HLA-DR+ lin-/dim colonic cells expressed markers associated with blood CD11c- HLA-DR+ lin-/dim plasmacytoid DC (BDCA2, BDCA4 and high levels of CD123) but a major subset expressed high levels of the Natural Killer (NK) marker CD56. CONCLUSION: Intestinal inflammation in UC is associated with the presence of a population of cells that share phenotypic features of both antigen presenting cells and NK cells. This novel population of human colonic cells may function in immune regulation or tissue repair. In addition, their increased presence in quiescent UC may be a marker of sub-clinical inflammatory activity
T1220 Negative Feedback Regulation of Pathogenic CD4+ T Cells By Increased Granulopoiesis Yasuhiro Nemoto, Takanori Kanai, Shuji Tohda, Teruji Totsuka, Ryuichi Okamoto, Kiichiro Tsuchiya, Tetsuya Fukuda, Hideo Yagita, Mamoru Watanabe Backgroud & Aims: Inflammatory bowel diseases (IBD) are characterized by massive infiltration of various innate and acquired immune cells in inflammatory sites. Most studies have so far focused on the capacity of innate immune cells to shape the adaptive immunity, and thus relatively little attention has been paid to the potential influence of acquired immunity on the innate immune system. However, it has been known that the circulating activated granulocytes are elevated with increased survival time in patients with severe IBD, suggesting an important role of granulocytes in chronic phase of IBD. As a clue, we have recently demonstrated that colitogenic CD4+ memory T cells reside in BM of colitic CD4+CD45RBhigh cell-transferred SCID mice. Methods: We here investigated if BM granulopoiesis was actually controlled by the presence of colitogenic BM CD4+ T cells. Results: We found that Gr1highCD11b+ polymorphonuclear granulocytes were significantly increased in colitic BM, resulting in the significant increase of granulocytes in the periphery of colitic mice. Of note, colitic BM CD4+ T cells were closely apposed to granulocytes, and produced high levels of IL-3, GM-CSF, and IL-17 as well as Th1 and Th17 cytokines. Consistently, In Vitro CFU assay revealed that G-, M-, and GM-colony formations were significantly induced by the supernatants from anti-CD3-stimulated colitic CD4+ T cells. Notably, the depletion of granulocytes in colitic mice by anti-Gr-1 mAb did not ameliorate colitis, but exacerbated the wasting disease with a markedly increased expansion of colitogenic CD4+ T cells in the periphery. Conclusions: Collectively, these results suggest that the increased granulopoiesis by pathogenic BM memory CD4+ T cells represents a negative feedback mechanism to control chronic and systemic inflammation.
T1218 Intestinal Dendritic Cells in Ulcerative Colitis Have Altered CD103 (Alpha-E) Expression - in Support of Dysregulation in Gut-Homing Siew C. Ng, Sophie Plamondon, Michael A. Kamm, Stella C. Knight, Andrew J. Stagg INTRODUCTION: Attraction of T lymphocytes to sites of inflammation is central to the inflammatory process, and is heavily influenced by specialized gut dendritic cells (DC). Gut DC induce expression of homing molecules on T cells that they activate. In the mouse, the ability to imprint gut homing is found in a population of intestinal DC that expresses the integrin chain CD103(alpha-E). Colonic DC from ulcerative colitis (UC) induce higher levels of gut-homing Beta 7 integrin on T cells than do DC from healthy tissue. Characterising the expression of CD103 by human intestinal disease in health and inflammatory bowel disease (IBD) is likely to increase our ability to alter inflammatory cell recruitment. AIMS & METHODS: Using multi-colour flow cytometry, CD103 expression was assessed on lamina propria mononuclear cell populations extracted from colonic tissue in UC patients (n=13) and controls (n=17). The proportion and number of CD103+ cells were determined. Level of CD103 expression was measured as an intensity ratio (IR) with reference to isotypematched control labelling. CD103 expression was compared on myeloid DC (CD11c+ HLADR+ lineage-/dim), CD11c- HLA-DR+ lineage-/dim cells and lymphocytes. RESULTS: In controls, lamina propria CD103+ cells comprised a major fraction of myeloid DC population (mean±SEM 37±3%), but were infrequent among the CD11c- HLA-DR+ lineage-/dim (6±3%; p<0.05) and lymphocyte (8±1%) populations. Level of CD103 expression by myeloid DC (IR=7.3±1.2) and lymphocytes (IR=6.7±2%), was significantly higher than that of CD11ccells (IR=3.5±0.7; p<0.05). There was no significant difference in proportion of DC expressing CD103 in paired samples from ileum and colon. In UC, proportion of lamina propria myeloid DC and CD11c- HLA-DR+ lineage-/dim cells expressing CD103 (myeloid DC: 22±5%; CD11c- cells: 0±3%) was significantly lower than for equivalent populations from controls(p<0.05). Absolute number of colonic CD103+ myeloid DC was significantly lower for UC than controls. (UC 22±9 vs. control 49±9 per mg tissue; p<0.05). In addition, colonic myeloid DC and CD11c- HLA-DR+ lineage-/dim cells from UC tissue expressed lower levels of CD103 than equivalent cells from control tissue (IR: 4±0.8 vs. 7±1.3 myeloid DC, p<0.05; IR: 1±0.2 vs. 3.0±0.7 CD11c- HLA-DR+ lineage-/dim cells, p<0.05 ). CONCLUSION: CD103+ myeloid DC are present in the human colon and small intestine. Loss of CD103+ colonic DC in UC may result from effects on recruitment of precursors, local differentiation and/or migration from the tissues. These findings support a role for dysregulated control of gut-homing by DC in IBD. REFERENCE: Rigby et al. Gastroenterol 2006
T1221 Deletion of P-Selectin Glycoprotein1 Accelerates the Onset and Worsens IL10-/- Colitis Jeffrey Brown, Goo Lee, Gery Grimm, Terrence A. Barrett Background: PSGL1 is a homing ligand expressed on numerous immune cells (eg T cells, macrophages, platelets) and endothelial surfaces. It functions as pan-ligand for P-, L-, and E-selectin. In addition to its homing role, it has been implicated in apoptosis. We and others have demonstrated it to be critical to effector cell trafficking in the small intestine and in the pathogenesis of murine ileitis. This study examined the role of PSGL1 in IL-10-/- colitis. Methods/Results: BL/6 IL-10-/- mice (IL-10-/-) were crossed to BL/6 PSGL1-/- to create double KO (d-KO) mice. IL-10-/- mice and d-KO mice were both fed a short course of piroxicam (60mg/250g chow x 5d rather than the standard 60mg/250g x 7d followed by 7d of 80mg/250g chow) and tissues were examined 14 and 28 days later. At day 14 IL10-/- mice developed early, but mild evidence of expected proximal colitis (colitis score 3.8±2.4 out of 24) with mild hyperplasia of crypts, but no ulceration or transmural lesions. D-KO mice demonstrated advanced colitis (15.3±1.5, p<0.01). Weight loss was more pronounced and systemic inflammation significantly increased (serum amyloid A ELISA) in dKO mice. Examination of mucosal cytokine mRNA by Real Time PCR demonstrated no significant difference in lymphocyte-derived cytokine (IFN-γ, TNF, IL-6) that was minimally elevated. However, IL-1β increased nearly 22-fold in d-KO vs. IL-10-/- mice. CXCL10 increased 10-fold in d-KO mice. Regulatory function was not impaired in d-KO mice as
A-509
AGA Abstracts
AGA Abstracts
first correlate that could have functional significance between an epigenetic modification at the level of IFNG DNA and pANCA reactivity in UC patients. These results may provide insight into identifying distinct regulatory mechanisms of cytokine expression in subsets of UC patients that can lead to improved diagnostics and selective therapeutic targets. 1) Am J Gastroenterol. 2002 Nov;97(11):2820-8.
T1217
Background The pathogenesis of ulcerative colitis (UC) is unclear, but enhancement of disease activity by usage of NSAIDs suggests involvement of prostanoid in its pathophysiology. Enhanced biosynthesis of prostaglandin (PG)D(2) has been suggested to contribute to inflammation in kidney or venular wall. Recently, PGD2 affects Th1/2 balance by stimulating Th2 cells via CRTH2 and suppressing Th1 cells via DP receptor In Vitro. However, the role of PGD2 in colonic mucosa is not studied at all. Thus we hypothesized that PGD2-CRTH2 may modulate colonic inflammation in UC. In this study we investigated the expression of enzymes for PGD2 synthesis and its relation to the activity of colitis. The role of L-PGDS using murine colitis model was also assessed. Methods Tissue samples were obtained by colonic biopsies from patients with UC or colonic polyps with informed consent. Th1/2 cell infiltration was studied immunohistochemically using antibody against CC chemokine receptor 5 (CCR5) and CRTH2. L-PGDS expression and Cox-2 expression were also investigated. Th1 related chemokine, MIP1-a and Th2 related enzymes, hematopoietic-type-prostaglandin D synthase (H-PGDS) and lipocalin-type-prostaglandin D synthase (L-PGDS) were studied by m-RNA expression using quantitative RT-PCR. C57Bl6 mice were treated with 3% dextran sodium sulfate drinking to induce colitis. Degree of inflammation was compared with L-PGDS -/- mice of the C57Bl6 background and control mice. Result CCR5 positive cells significantly increased in inflamed mucosa and it pararelled with disease activity. Mip1 alpha expression well co-related with CCR5. CRTH2 -positive cells was predominantly observed in the mildly inflamed or the margin of inflamed mucosa and decreased in severely active UC patients. mRNA expression of L-PGDS was increased in UC patients and it pararelled with disease activity. Co-localization of L-PGDS and Cox 2 were observed in mesenchymal cells in lamina propria in UC patients. On the contrary, H-PGDS did not differ from control mucosa. L-PGDS -/- mice showed lower disease activity than control mice. Conclusion: We first reported presence of L-PGD synthase in the Cox-2 + cells in UC patients and that only lipocalin type increased with disease activity. Infiltration of PGD2 receptor + cells also suggests PGD2 play some role in pathophysiology of UC. Animal model study suggests that PGD2 derived from L-PGDS + cells play proinflammatory role in UC.
A Novel Population of CD56+ HLA-DR+ Colonic Lamina Propria Cells Is Associated with Inflammation in Ulcerative Colitis Siew C. Ng, Sophie Plamondon, Hafid O. Al-Hassi, Nicholas R. English, Nichola L. Gellatly, Michael A. Kamm, Stella C. Knight, Andrew J. Stagg INTRODUCTION: The immunopathology of ulcerative colitis (UC) relates to an inappropriate mucosal immune response to constituents of the intestinal microbiota in genetically susceptible individuals. HLA-DR+ lin-/dim (lin = anti-CD3,14,16,19,34) cells extracted from human intestinal tissue contain CD11c+ myeloid dendritic cells (DC) that contribute to the immunoregulatory events that normally limit inflammatory responses to commensal bacteria. Also present within the HLA-DR+ lin-/dim population are hitherto poorly characterized CD11c- cells. We hypothesized that this population in the gut may also contribute to intestinal inflammation in active UC AIMS & METHODS: HLA-DR+ lin-/dim cells were identified in freshly isolated lamina propria mononuclear cells by multicolour flow cytometry, from patients with UC (n=48) and controls (n=22). The proportion and number of CD11c+ and CD11c- cells within this population were determined. Surface expression of the activation/maturation markers CD40, CD86, Toll-like receptors (TLR), TLR-2, TLR-4, and the natural killer cell marker, CD56 was assessed on each cell population. Morphology was assessed by electron microscopy and T cell stimulatory capacity measured in allogenic mixed leucocyte reaction (MLR). RESULTS: Lamina propria colonic HLA-DR+ lin-/dim cells, of the CD11c-, but not the CD11c+ subset, were significantly increased in inflamed tissue of patients with UC compared with control tissue (UC 447±94 versus Control 104±17 per mg; p<0.001). Numbers of CD11c- HLA-DR+ lin-/dim cells decreased after resolution of macroscopic inflammation. Nonetheless, CD11c- HLA-DR+ lin-/dim cells were significantly increased in non-inflamed tissue of UC patients compared with colonic tissue from healthy subjects (p<0.05). In UC, these CD11c- cells expressed CD40, CD86, TLR-2 and TLR-4 at lower levels than on their CD11c+ counterparts and were weakly stimulatory in an MLR. Few CD11c- HLA-DR+ lin-/dim colonic cells expressed markers associated with blood CD11c- HLA-DR+ lin-/dim plasmacytoid DC (BDCA2, BDCA4 and high levels of CD123) but a major subset expressed high levels of the Natural Killer (NK) marker CD56. CONCLUSION: Intestinal inflammation in UC is associated with the presence of a population of cells that share phenotypic features of both antigen presenting cells and NK cells. This novel population of human colonic cells may function in immune regulation or tissue repair. In addition, their increased presence in quiescent UC may be a marker of sub-clinical inflammatory activity
T1220 Negative Feedback Regulation of Pathogenic CD4+ T Cells By Increased Granulopoiesis Yasuhiro Nemoto, Takanori Kanai, Shuji Tohda, Teruji Totsuka, Ryuichi Okamoto, Kiichiro Tsuchiya, Tetsuya Fukuda, Hideo Yagita, Mamoru Watanabe Backgroud & Aims: Inflammatory bowel diseases (IBD) are characterized by massive infiltration of various innate and acquired immune cells in inflammatory sites. Most studies have so far focused on the capacity of innate immune cells to shape the adaptive immunity, and thus relatively little attention has been paid to the potential influence of acquired immunity on the innate immune system. However, it has been known that the circulating activated granulocytes are elevated with increased survival time in patients with severe IBD, suggesting an important role of granulocytes in chronic phase of IBD. As a clue, we have recently demonstrated that colitogenic CD4+ memory T cells reside in BM of colitic CD4+CD45RBhigh cell-transferred SCID mice. Methods: We here investigated if BM granulopoiesis was actually controlled by the presence of colitogenic BM CD4+ T cells. Results: We found that Gr1highCD11b+ polymorphonuclear granulocytes were significantly increased in colitic BM, resulting in the significant increase of granulocytes in the periphery of colitic mice. Of note, colitic BM CD4+ T cells were closely apposed to granulocytes, and produced high levels of IL-3, GM-CSF, and IL-17 as well as Th1 and Th17 cytokines. Consistently, In Vitro CFU assay revealed that G-, M-, and GM-colony formations were significantly induced by the supernatants from anti-CD3-stimulated colitic CD4+ T cells. Notably, the depletion of granulocytes in colitic mice by anti-Gr-1 mAb did not ameliorate colitis, but exacerbated the wasting disease with a markedly increased expansion of colitogenic CD4+ T cells in the periphery. Conclusions: Collectively, these results suggest that the increased granulopoiesis by pathogenic BM memory CD4+ T cells represents a negative feedback mechanism to control chronic and systemic inflammation.
T1218 Intestinal Dendritic Cells in Ulcerative Colitis Have Altered CD103 (Alpha-E) Expression - in Support of Dysregulation in Gut-Homing Siew C. Ng, Sophie Plamondon, Michael A. Kamm, Stella C. Knight, Andrew J. Stagg INTRODUCTION: Attraction of T lymphocytes to sites of inflammation is central to the inflammatory process, and is heavily influenced by specialized gut dendritic cells (DC). Gut DC induce expression of homing molecules on T cells that they activate. In the mouse, the ability to imprint gut homing is found in a population of intestinal DC that expresses the integrin chain CD103(alpha-E). Colonic DC from ulcerative colitis (UC) induce higher levels of gut-homing Beta 7 integrin on T cells than do DC from healthy tissue. Characterising the expression of CD103 by human intestinal disease in health and inflammatory bowel disease (IBD) is likely to increase our ability to alter inflammatory cell recruitment. AIMS & METHODS: Using multi-colour flow cytometry, CD103 expression was assessed on lamina propria mononuclear cell populations extracted from colonic tissue in UC patients (n=13) and controls (n=17). The proportion and number of CD103+ cells were determined. Level of CD103 expression was measured as an intensity ratio (IR) with reference to isotypematched control labelling. CD103 expression was compared on myeloid DC (CD11c+ HLADR+ lineage-/dim), CD11c- HLA-DR+ lineage-/dim cells and lymphocytes. RESULTS: In controls, lamina propria CD103+ cells comprised a major fraction of myeloid DC population (mean±SEM 37±3%), but were infrequent among the CD11c- HLA-DR+ lineage-/dim (6±3%; p<0.05) and lymphocyte (8±1%) populations. Level of CD103 expression by myeloid DC (IR=7.3±1.2) and lymphocytes (IR=6.7±2%), was significantly higher than that of CD11ccells (IR=3.5±0.7; p<0.05). There was no significant difference in proportion of DC expressing CD103 in paired samples from ileum and colon. In UC, proportion of lamina propria myeloid DC and CD11c- HLA-DR+ lineage-/dim cells expressing CD103 (myeloid DC: 22±5%; CD11c- cells: 0±3%) was significantly lower than for equivalent populations from controls(p<0.05). Absolute number of colonic CD103+ myeloid DC was significantly lower for UC than controls. (UC 22±9 vs. control 49±9 per mg tissue; p<0.05). In addition, colonic myeloid DC and CD11c- HLA-DR+ lineage-/dim cells from UC tissue expressed lower levels of CD103 than equivalent cells from control tissue (IR: 4±0.8 vs. 7±1.3 myeloid DC, p<0.05; IR: 1±0.2 vs. 3.0±0.7 CD11c- HLA-DR+ lineage-/dim cells, p<0.05 ). CONCLUSION: CD103+ myeloid DC are present in the human colon and small intestine. Loss of CD103+ colonic DC in UC may result from effects on recruitment of precursors, local differentiation and/or migration from the tissues. These findings support a role for dysregulated control of gut-homing by DC in IBD. REFERENCE: Rigby et al. Gastroenterol 2006
T1221 Deletion of P-Selectin Glycoprotein1 Accelerates the Onset and Worsens IL10-/- Colitis Jeffrey Brown, Goo Lee, Gery Grimm, Terrence A. Barrett Background: PSGL1 is a homing ligand expressed on numerous immune cells (eg T cells, macrophages, platelets) and endothelial surfaces. It functions as pan-ligand for P-, L-, and E-selectin. In addition to its homing role, it has been implicated in apoptosis. We and others have demonstrated it to be critical to effector cell trafficking in the small intestine and in the pathogenesis of murine ileitis. This study examined the role of PSGL1 in IL-10-/- colitis. Methods/Results: BL/6 IL-10-/- mice (IL-10-/-) were crossed to BL/6 PSGL1-/- to create double KO (d-KO) mice. IL-10-/- mice and d-KO mice were both fed a short course of piroxicam (60mg/250g chow x 5d rather than the standard 60mg/250g x 7d followed by 7d of 80mg/250g chow) and tissues were examined 14 and 28 days later. At day 14 IL10-/- mice developed early, but mild evidence of expected proximal colitis (colitis score 3.8±2.4 out of 24) with mild hyperplasia of crypts, but no ulceration or transmural lesions. D-KO mice demonstrated advanced colitis (15.3±1.5, p<0.01). Weight loss was more pronounced and systemic inflammation significantly increased (serum amyloid A ELISA) in dKO mice. Examination of mucosal cytokine mRNA by Real Time PCR demonstrated no significant difference in lymphocyte-derived cytokine (IFN-γ, TNF, IL-6) that was minimally elevated. However, IL-1β increased nearly 22-fold in d-KO vs. IL-10-/- mice. CXCL10 increased 10-fold in d-KO mice. Regulatory function was not impaired in d-KO mice as
A-509
AGA Abstracts
AGA Abstracts
first correlate that could have functional significance between an epigenetic modification at the level of IFNG DNA and pANCA reactivity in UC patients. These results may provide insight into identifying distinct regulatory mechanisms of cytokine expression in subsets of UC patients that can lead to improved diagnostics and selective therapeutic targets. 1) Am J Gastroenterol. 2002 Nov;97(11):2820-8.