Immune parameters in euthymic bipolar patients and normal volunteers

ELSEVIER

Journal of Affective Disorders 32 (1994) 149-156

Immune

journalof AFFECTIVE DISORDERS

parameters in euthymic bipolar patients and normal volunteers Mark Hyman Rapaport

a,b,*

aDepartment of Psychiatry, University of California at San Diego, San Diego, CA, USA ’ Psychiatric Service, San Diego Veterans Administration Medical Center, San Diego, CA, USA Received 18 April 1994; revised 24 June 1994; accepted 13 July 1994

Abstract Immune system were in euthymic patients and normal volunteers. A review the existing suggested that patients might more likely signs immune activation. interleukin-2 receptors, circulating lymphocyte markers, were measured. Euthymic patients and volunteers did not on any these measures. Furthermore, bipolar patients not be by medication or gender. there no evidence immune system in euthymic patients. Keywords:

Bipolar

Flow

1. Introduction

The investigation of immune chiatry is challenging because interface between two rapidly Revitalization of interest in this work demonstrating changes in

function in psyit represents an changing fields. area began with immune function

* Address: Psychopharmacology Research Program, Department of Psychiatry, University of California at San Diego School of Medicine, 8950 Villa La Jolla Drive, Ste 2243, La Jolla, CA 92037, USA. Fax: (1) (619) 540-1491.

SIL-2R;

Autoantibody

with stress (Schleifer et al., 1983; Glaser et al., 1986; Irwin et al., 1987a; Irwin et al., 1987b). There have been an increasing number of studies assessing the status of the immune system in depression, schizophrenia and manic depression (Schleifer et al., 1984; Schleifer et al., 1989; Kronfol et al., 1988; Kronfol 1988; Kronfol et al., 1984; Irwin et al., 1987~; Irwin et al., 1990; Darko et al., 1989; Ganguli et al., 1987; Maes et al., 1990; McAllister et al., 1989; Muller et al., 1987). Our group has focused on investigations of immune activation in schizophrenia. We have consistently found that some schizophrenic patients have increased serum-soluble interleukin-2 receptors (SIL-2Rs) (Rapaport et al., 1989; Rapaport et al.,

0165-0327/94/$07.00 0 1994 Elsevier Science B.V. All rights reserved SSDI 0165.0327(94)00048-4

150

M.H. Rapaport /Journal

of AffectiL,e Disorders 32 (1994) 149-156

1993). This finding is not a neuroleptic effect (Rapaport et al., 1991; Rapaport and Lohr, submitted) and we have replicated in different ethnic groups as well (Rapaport et al., 1994). One crucial step in ascertaining whether a finding is of true clinical importance is the evaluation of its specificity. Thus far, we have demonstrated that markedly increased serum SIL-2Rs are not present in panic disorder (Rapaport and Stein, 1994) social phobia (Rapaport and Stein, submitted) or in major depression (Rapaport and Irwin, unpubl. data). Bipolar disorder is an important comparison group because it is an example of a psychiatric disorder which may manifest psychosis. Bipolar patients have been reported to have an increased prevalence of thyroid autoantibodies, changes in circulating phenotypic lymphocyte profiles and may even present with leukocytosis and fever during mania (Kronfol et al., 1988; Kronfol and House, 1988; Kronfol et al., 1984; Calabrese et al., 1987; Haggerty et al., 1987; Haggerty et al., 1990; Sengar et al., 1982; Wahlin et al., 1984; Deniker et al., 1978; Lazarus et al., 1986). However, findings of immune activation in bipolar disorder have been confounded by lithium Investigators have suggested that treatment. lithium may serve as an adjuvant for autoantibody production and may cause an increase in in vitro and in vivo functional immune measures (Albrecht and Hopf, 1982; Balazs et al., 1989; Jones et et al., 1988; Hart, 1988; al., 1990; Fuggeta O’Riordan et al., 1986). We recently demonstrated that normal volunteers administered lithium at therapeutic levels for 28 days had a mild (50 U/ml) increase in serum SIL-2Rs but did not have an increase in either antithyroid antibody prevalence or titers (Rapaport et al., in press). This study investigates a series of immune parameters in euthymic bipolar patients and matched normal volunteers in an attempt to ascertain if immune activation is a trait marker of bipolar illness. It was postulated that bipolar individuals would have increased serum SIL-2Rs, an increased prevalence of circulating phenotypic markers of immune activation (increased CD4 cells, the increased presentation of CD25, increased presentation of HLA-DR on lymphocytes and increased CD29/CD4-positive cells) as well

as an increased bodies.

prevalence

of thyroid

autoanti-

2. Methods The men and women in this study were selected from patient and control candidates who contacted the NIMH-funded Mental Health Outpatient Clinical Research Center (MHCRC) in the Department of Psychiatry at University of California at San Diego. Subjects gave informed written consent to participate in research and were recruited by means of advertisements in newspapers, flyers, articles in newsletters, public service announcements on radio and television, solicitations from community physicians, referrals from patient advocacy groups and word of mouth. All research candidates had a 30-40-min preliminary semistructured psychiatric and medical telephone interview performed by trained MHCRC staff. Individuals who were believed to have major depression, bipolar disorder or no psychiatric diagnosis and to be medically healthy were given an appointment for an evaluation. Candidates then underwent a medical history and physical examination, a complete blood count and SMA-20, urine analysis, a thyroid test and, if thought necessary, a urine toxicological screen. Subjects were interviewed using the Structured Clinical Interview for DSM III-R (SCID) (Spitzer et al., 1988). Family history was ascertained using the MHCRC-screening form which asked participants about the presence of psychiatric illness in maternal and paternal grandparents, aunts and uncles, parents, siblings and offspring. Subjects were evaluated by research fellows, psychologists and research assistants who underwent annual SCID training and semi-annual inter-rater reliability retraining. (K scores for these raters were 0.82 and 0.86.) Final diagnoses were made by consensus teams and were formulated by evaluating all available information, including the SCID interview, the clinical interview and review of all prior psychiatric records that could be obtained. To be included in this analysis subjects had to meet DSM-III-R criteria for bipolar disorder, in remission or no diagnosis, have a normal physical

M.H. Rapaport /Journal

examination, and laboratory values that fell within the normal range. (16 patients met criteria for bipolar I disorder and 10 patients met criteria for bipolar II disorder. Preliminary analyses found no immune parameter differences between these two groups.) 30 ml of blood was collected between 7:30 and 10:OO.

2.1. Flow cytometry

151

ofAffectil)e Disorders 32 (1994) 149-156

generated to distinguish the lymphocyte, monocyte and granulocyte populations. An elliptical gate was set around the lymphocyte population to eliminate the monocytes, granulocytes, unlysed red cells and dead cells from analysis. An isotype control directly conjugated with FITC and PE was run with each set of samples. The monoclonal antibody results were reported as a percentage of the lymphocyte population.

preparation

Samples, maintained at room temperature, were stained and assayed within 24 h of collection. Cells were stained using a direct labeling with fluorescent antibodies procedure (Becton Dickinson, 1986). 100 ~1 of whole blood was added to 20 ~1 of fluorescently labeled monoclonal antibodies (mouse recombinant monoclonal antibodies) CD3(FITC), CD4(FITC), CD8 (FITC), CD16(FITC), CD19(FITC), CD25(FITC), HLA-DR(FITC), CD19(FITC)/ HLA-DR(PE), CD19(FITC)/ CDS(PE), CD29(FITC)/CD4(PE) and isotopic controls conjugated with fluorescein isothiocyanate (FIT0 and phycoerthyrin (PE) (AMAC, Westbrook, ME) in transparent 5-ml glass tubes. The mixture was vortexed and left for 15 min at room temperature in the dark. Then, 2 ml of 1 x FACS Lysing Solution was added to the tubes (Becton Dickinson Immunocytometry Systems, San Jose, CA). Each tube was vortexed gently and incubated for 10 min at room temperature in the dark. Next, samples were centrifuged at 300 x g for 5 min at room temperature and the supernatants were aspirated. 1 ml of 1 x PBS was added to the pellets and the tubes were gently vortexed. The tubes were again centrifuged at 200 X g for 5 min at room temperature. The supernatants were aspirated and each pellet was resuspended in 0.5 ml of 1 X PBS. The tubes were stored at 4°C in the dark until the samples were analysed by flow cytometry. 5000 lymphocytes were analysed on an Ortho Cyto-Fluorograf 50-H (Becton Dickinson Immunocytometry Systems) equipped with a Model 2150 Data Processing System. For fluorescence excitation and generation of the scatter signal, a 5-W argon laser was used at 488 nm wavelength. A forward vs. right-angle scatter cytogram was

2.2. Soluble interleukin-2

receptor assay

A commercially available sandwich enzyme immunoassay was used for the determination of SILl-2Rs (T-cell Diagnostics, Cambridge, MA). 50 ~1 of either standard or samples were pipetted in duplicate into the wells of the anti-IL-2R monoclonal antibody-coated polystyrene microtiter plate. 10 ~1 of HRP-conjugated anti-IL-2R antibody was added to each well and the plate was agitated for 15 s. The plate was then covered and incubated at room temperature for 3 h on a rotator set at 100 rpm. The sample was aspirated from the wells and the plate was washed 3 x with 350 ~1 of phosphate-buffered saline (PBS wash buffer). 100 ~1 of chromogen solution (o-phenylenediamine) solution was then added to the wells and incubated at room temperature for 30 min. 50 ~1 of 2 N H,SO, was added to each well and gently mixed. The plate was read in an automated ELISA reader set at 490 nm. The samples were assayed in duplicate and the mean value was reported. 1 U was equivalent to 3 pg/ml. The minimum level of sensitivity of the assay was 50 U/ml and the inter- and intraassay coefficients of variation were 5 and 3%, respectively (Kurman et al., 1992).

2.3. Mitogen stimulation Lymphocytes were purified using standard techniques and 2.5 x 10h lymphocytes/ml were cultured using a standard protocol (Current Protocols in Immunology, 1992). A standard curve was developed for PHA and 50 pg/ml was chosen as optimal. Cultures were stimulated with 50

M. H. Rapaport /Journal

152

pg/ml PHA for 48 h and supernatants harvested. Samples were frozen at -70°C they were assayed.

2.4. Supernatant

of Affecticbe Disorders 32 (I 994) 149-156

were until

IL-2 assay

IL-2 was measured blindly using a commercially available, competitive enzyme immunoassay (Assay Research, College Park, MD). Samples were split into duplicate fractions and run simultaneously. The assay relies on the competition of biotinylated IL-2 with specific IL-2 in standards or samples for a limited number of specific antibody binding sites. 100 ~1 of primary anti-IL-2 antibody was plated into each well of a 96-well ELISA plate and incubated for 2 h at room temperature. The unbound antibody was removed by washing 5 x with buffer. 50 ~1 of either standard or unknown sample was pipetted in the wells and then 50 ~1 of conjugated IL-2 was added. (The concentrations for the standard curve range from 0.005 to 5 ng.) The mixture of biotinylated IL-2 and standard/sample was incubated with the antibody for 2 h and then washed 5 x with buffer. A 1 : 2000 dilution of streptavidinconjugated alkaline phosphatase was added and incubated with the samples at room temperature for 45 min. The streptavidin alkaline phosphatase was removed by five washes with buffer and 100 ~1 of substrate (p-nitrophenyl phosphate disodium; 2 mg/ml in 10 mM NaHCO,, 12 mM Na ,CO,) was added to each well. The resultant color was read at 405 nm at 24 h. The data were analysed by computer-assisted logit-log transformation of the resultant optical densities (Microtiter Plate Manager; Bio-Rad, Richmond, CA). The limit of sensitivity of each assay is 0.1 ng/ml, with intra- and interassay coefficients of variation of 7 and 15%, respectively (Paciotti et al., 1992).

2.5. Antithyroid

antibody

assays

Samples were assayed for levels of thyroid antimicrosomal antibodies and antithyroglobulin antibodies. The antimicrosomal antibody assay was an RIA with a sensitivity of 10 U/ml and an

intraassay variation of < 8% and an interassay variation of < 11%. The normal range is < 25 U/ml (Fisher and Pandian, 1991). The antithyroglobulin assay employed was a radio-binding assay employing a goat anti-human IgG. The sensitivity of the assay was 10 U/ml with an intraassay variation of < 5% and an interassay variation of < 8%. The normal range is < 20 U/ml (Fisher and Pandian, 1991). 2.6. Statistics The data were analysed for homogeneity of variance and normal distribution. SIL-2Rs values were found to not be homogeneous and so they were log-transformed. ANOVAs were performed to contrast bipolar patients and normal volunteers. Since the number of subjects with positive autoantibody titers was small, these data did not undergo formal statistical analyses.

3. Results The mean age of the 26 bipolar patients was 41.0 years (SD 10.6) and the mean age of the 34 volunteers was 39.4 years (SD 12.1). As illustrated in Table 1, bipolar subjects and normal volunteers did not differ in terms of any of the circulating phenotypic lymphocyte markers evaluated in

Table 1 A comparison of circulating phenotypic in bipolar subjects and controls

CD3 CD4 CD8 CD16 CD19 CD25 HLADR CD19HLA CD19CD5 CD29CD4 CD4CD8

lymphocyte

markers

Bipolar subjects (n = 26)

Normal volunteer (n = 34)

df

F

P

73.2 (5.9) 47.6 (7.3) 27.4 (5.7) 10.2 (4.5) 8.6 (3.6) 5.5 (3.7) 13.18 (3.4) 7.62 (3.5) 1.80 (1.5) 25.0 (6.1) 1.8 (0.61)

73.4 (6.2) 44.6 (7.5) 30.1 (8.1) 11.2 (6.9) 8.5 (5.1) 4.5 (2.7) 14.1 (6.8) 7.1 (4.6) 1.80 (1.7) 24.2 (5.6) 1.6 (0.54)

1,58 1,58 1,58 1,58 1,5X 1,58 1,58 1,58 1,58 1,58 1,58

0.015 2.39 1.89 0.151 0.008 0.102 0.470 0.153 0.071 0.317 2.22

0.903 0.128 0.175 0.699 0.926 0.751 0.496 0.697 0.791 0.576 0.142

of Affective

M.H. Rapaport /Journal Table 2 A comparison

of circulating

CD3 CD4 CD8 CD16 CD19 CD25 HLADR CD19HLA CD19CD5 CD29CD4 CD4CD8

phenotypic

lymphocyte

markers

in medicated

and unmedicated

bipolar

153

subjects

and normal

Medicated bipolar subjects (n = 14)

Unmedicated bipolar subjects (n = 12)

Normal volunteers (n = 34)

df

F

P

73.7 (7.1) 48.3 (8.1) 27.3 (7.0) 10.5 (4.9) 8.88 (4.1) 6.01 (4.4) 13.14 (3.7) 7.53 (3.9) 2.15 (1.9) 26.18 (7.5) 1.92 (0.71)

72.6 (4.2) 46.9 (6.4) 27.6 (4.0) 9.82 (4.2) 8.41 (3.2) 4.92 (2.9) 13.22 (3.0) 7.72 (3.2) 1.36 (0.85) 23.78 (3.7) 1.76 (0.47)

73.4 (6.2) 44.6 (7.5) 30.1 (8.1) 11.2 (6.9) 8.5 (5.1) 4.5 (2.7) 14.1 (6.8) 7.1 (4.6) 1.89 (1.7) 24.2 (5.6) 1.6 (0.54)

2,57 2,57 2,57 2,57 2,57 2,57 2,57 2,57 2,57 2,57 2,57

0.114 1.29 0.978 0.118 0.630 0.597 0.211 0.082 0.825 0.679 1.34

0.893 0.283 0.387 0.889 0.963 0.559 0.794 0.921 0.443 0.511 0.269

this study. The bipolar patients and normal volunteers did not differ in serum SIL-2R levels, 255.1 (120.8 U/ml) vs. 265.9 (145.0) U/ml> (df = 1,58; F = 0.036, P = 0.850). The two groups also did not differ in terms of PHA-stimulated purified lymphocyte culture supernatant IL-2 levels, 1.5 (1.03) ng/ml for the bipolar subjects vs. 1.09 (0.80) ng/ml for the controls; (df = 1,58, F = 2.937, P = 0.92). Antimicrosomal and antithyroglobulin antibodies were measured in 14 bipolar patients and 19 controls. None of the bipolar patients and only 1 of the controls was positive for antimicrosomal or antithyroglobulin antibody titers.

Table 3 A comparison of circulating phenotypic in bipolar male and female subjects

CD3 CD4 CD8 CD16 CD19 CD25 HLADR CDlYHLA CD19CD5 CD29CD4 CD4CD8

Disorders 32 (1994) 149-156

lymphocyte

markers

Bipolar Male Subjects (n = 9)

Bipolar Female Subjects (n = 17)

DF

F

P

72.44 46.82 28.53 12.10 7.63 5.46 12.17 6.88 1.47 25.40 1.70

73.61 48.11 26.88 9.21 9.21 5.53 13.71 8.01 1.96 24.90 1.91

1,24 1,24 1,24 1,24 1,24 1,24 1,24 1,24 1,24 1,24 1,24

0.223 0.176 0.482 2.49 1.08 0.002 1.21 0.594 0.269 0.037 0.699

0.641 0.679 0.494 0.128 0.310 0.989 0.281 0.452 0.608 0.849 0.411

(5.7) (4.65) (5.41) (5.37) (2.93) (4.39) (3.32) (2.67) (0.80) (3.31) (0.40)

(6.11) (8.49) (5.97) (3.90) (4.00) (3.57) (3.44) (3.97) (1.83) (7.29) (0.69)

volunteers

In an attempt to determine whether a medication effect might be confounding the data, we performed an analysis contrasting patients who had been medication free for at least 60 days (n = 4) or never medicated (n = 8) with patients who had been stabilized on lithium carbonate monotherapy for at least 60 days (n = 14) and normal volunteers (n = 34). The three groups did not differ in age (42.7 (8.2) years vs. 41.1 (12.3) years vs. 39.4 (12.1) years.) As illustrated in Table 2, there were, no significant differences in circulating lymphocyte phenotypic markers between any of the three groups. The three groups also had similar serum SIL-2R levels (222.2 (60.4) U/ml vs. 283.3 (152.0) U/ml vs. 265.9 (145.0) U/ml: df = 2,57; F = 0.58; P = 0.5) and supernatant IL-2 levels (1.33 (0.89) ng/ml vs. 1.64 (1.2) ng/ml vs. 1.09 (0.80) ng/ml: df = 2,57; F = 1.83; P = 0.16). In a preiiminary analysis, we contrasted our bipolar patients by gender. There were 9 men and 17 women with a mean age of 40.9 (12.0) years for men and 42.4 (9.9) years for the women. As demonstrated in Table 3, there were no statistically significant differences between bipolar men and women with respect to circulating lymphocyte phenotype markers. The mean serum SIL-2R levels were 312.2 (175.5) U/ml for the men and 224.8 (67.6) U/ml for the women (df = 1,24; F = 3.34; P = 0.08). The mean lymphocyte culture supernatant IL-2 levels were 1.44 (1.13) ng/ml

154

M.H. Rapaport /Journal

ofAffectice

for the men and 1.53 (1.010) ng/ml for the women (df = 1,24; F = 0.038, P = 0.85.)

4. Discussion Euthymic bipolar patients and normal controls had similar circulating phenotypic lymphocyte marker percentages, serum SIL-2R levels, supernatant IL-2 levels and antithyroid antibody prevalence. Although it is possible that there might be alterations in some other immune parameter, such as CD38/CD8 or CD45ra/CD4 populations, there was no evidence of immune activation in euthymic bipolar subjects in this study. The finding that thyroid antibody prevalence was similar for patients and controls differ from some reports in the literature. The majority of these studies report prevalence rates of 9-20% (Haggerty et al., 1987; Haggerty et al., 1990; Calabrese et al., 1985; Lazarus et al., 1986) and the preponderance of autoantibody-positive patients were either rapid-cycling patients or bipolar patients in a mixed mood state (Haggerty et al., 1987; Cowdry et al., 1983). Therefore, it is possible that the presence of antithyroid antibodies at rates greater than normally found in the population only occurs in specific symptomatic subgroups of bipolar patients. This also fits with data from the autoimmune literature which indicates that levels of specific autoantibodies may vary widely over time (Vrethem, et al., 1992). An alternative explanation for this finding is that the sample size reported here is relatively small. Yet, even so, if the prevalence of antithyroid antibody-positive bipolar patients were truly in the 9-20% range, some bipolar subjects should be autoantibody-positive. The preliminary data found that lithium treatment did not alter circulating lymphocyte phenotypic surface marker percentages. This differs from Wahlin et al. (1984) who claimed that lithium perturbed CD4 and CD8 cell numbers; however, a statistical analysis of their data did not demonstrate significant differences in these phenotypic markers before and after lithium treatment (Wahlin et al., 1984). The finding that lithium treatment did not affect serum SIL-2Rs also is intriguing. On the surface, it contradicts a recent

Disorders 32 (1994) 149-156

study from our laboratory where we demonstrated that normal controls treated with lithium for 28 days had a slight (50 U/ml) but significant increase in serum SIL-2Rs (Rapaport et al., 1984). Several factors may help account for this discrepancy. Review of the current data show that lithium-treated bipolar subjects did have a slight increase in serum SIL-2Rs (283.3 (150.2) U/ml for lithium-treated subjects vs. 222.2 (60.4) U/ml for medication-free patients and 265.9 (145.0) U/ml for normal volunteers) but this increase was not statistically significant. Thus, in both instances, we found slight elevations in serum SIL-2R levels with lithium treatment but these elevations did not exceed the normal reference range for the assay (Rubin and Nelson, 1990) and probably are not clinically significant. A second explanation for this finding was presented in a recent study by Ozdemir and colleagues who found that chronic lithium treatment did not cause any of the hematologic changes which are frequently associated with acute lithium administration (Ozdemir et al., 1994). And, although there are some studies in the literature indicating that acute lithium treatment may augment the functional activity of lymphocytes, no longitudinal in vitro data exist to suggest that chronic treatment augments immune function (Albrecht and Hopf, 1982; Solomon et al., 1969; Jones et al., 1990; Fuggeta et al., 1988; Hart, 1988; O’Riordan et al., 1986). When immune measures in bipolar patients were analysed according to gender, no significant differences emerged. There was a weak trend toward men having slightly higher serum SIL-2Rs than women but the sample size was small and both values fell well within the normal range of the assay (Rubin and Nelson, 1990). And, a review of previous studies have not found gender differences in serum SIL-2R levels (see Rubin and Nelson, 1990). In conclusion, euthymic bipolar patients did not differ significantly from matched normal volunteers. In a preliminary analysis, neither lithium treatment nor gender differences seemed to alter this finding. Therefore, it is reasonable to assume that euthymic bipolar patients are not immunologically different from controls. This implies that

M.H. Rapaport /Journal

of Affective Disorders 32 (1994) 149-156

the immune differences previously reported in symptomatic bipolar patients probably represent state dependent effect (Schiffer et al., 1986; Kronfol and House, 1988; Kronfol et al., 1984; Haggerty et al., 1987; Haggerty et al., 1990; Calabrese et al., 1985; Lazarus et al., 1986).

Acknowledgements

This work is MOlRR00827 and acknowledge Gary for their technical

supported by MH 3091416, UCSD RS162-M. We wish to Anderson and Nancy O’Shea support.

References Albrecht, _I. and Hopf, U. (1982) Humoral autoimmune phenomena under long-term treatment with lithium with special regard to thyroidal autoantibodies. Klin. Wochenschr. 60, 1501-1504. Balazs, C., Kiss, E. and Farid, N. (1989) Effect of lithium on chemiluminescence of polymorphonuclear granulocytes and mononuclear cells in peripheral blood. Acta Med. Hung. 46, 31-42. Becton Dickinson Monoclonal Antibody Source Book. 2nd Ed. (1986) Direct immunofluorescence staining of cell surface antigens in unseparated blood. Calabrese, J.R., Gulledge, A.D., Hahn, K., Skwerer, R., Kotz, M., Schumacher, O.P., Gupta, M.K., Krupp, N. and Gold, P.W. (1985) Autoimmune thyroiditis in manic-depressive patients treated With lithium. Am. J. Psychiatry 142, 1318-1321. Calabrese, J.R., Kling, M.A. and Gold, P.W. (1987) Alterations in immunocompetence during stress, bereavement, and depression. Am. J. Psychiatry 144, 1123-1134. Cowdry, R.W., Wehr, T.A., Zis, A.P. and Goodwin, F.K. (1983) Thyroid abnormalities associated with rapid-cycling bipolar illness. Arch. Gen. Psychiatry 40, 414-420. Current Protocols in Immunology. Greene Publishing and Wiley-Interscience, New York, NY, 1992. Darko, D.F., Gillin, J.C., Risch, C., Bulloch, K., Golshan, S., Tasevska, Z. and Hamburger, R.N. (1989) Mitogen-stimulated lymphocyte proliferation and pituitary hormones in major depression. Biol. Psychiatry 26, 145-155. Deniker, P., Eyquem, R., Bernheim, R., Loo, H. and Delarue, P. (1978) Thyroid autoantibody levels during lithium therapy. Neuropsychobiology 4, 270-275. Fisher, D.A. and Pandian, M.R. (1991) Antithyroid Antibodies: Antithyroglobulin, Antimicrosomal, Antithyroid Peroxidase. Nichols Institute, pp. l-6. Fuggeta, M.P., Alvino, E., Romani, L., Grohmann, U., Potenza, C. and Guiliani, A. (1988) Increase of natural

155

killer activity of mouse lymphocytes following in vitro and in vivo treatment with lithium. Immunopharmacol. Immunotoxicol. 10, 79-91. Ganguli, R., Rabin, B.S., Kelly, R.H., Lyte, M. and Ragu, U. (1987) Clinical and laboratory evidence of autoimmunity in acute schizophrenia. Ann. N.Y. Acad. Sci. 496, 676-85. Glaser, R., Kiecolt-Glaser, J.K., Stout, J.C., Tarr, K.L., Speicher, C.E. and Holiday, J.E. (1986) Stress related impairments in cellular immunity. Psychiatric Res. 16, 233-239. Haggerty, J.J., Evans, D.L., Golden, R.N., Pedersen, C.A., Simon, J.S. and Nemeroff, C.B. (1990) The presence of antithyroid antibodies in patients with affective and nonaffective psychiatric disorders. Biol. Psychiatry 27, 51-60. Haggerty, J.J., Simon, J., Evans, D.L. and Nemeroff, C.B. (1987) Relationship of serum TSH concentration and antithyroid antibodies to diagnosis and DST response in psychiatric inpatients. Am. J. Psychiatry 144, 1491-1493. Hart, D.A. (1988) Lithium potentiates antigen-dependent stimulation of lymphocytes only under suboptimal conditions Int. J. Immunopharmacol. 10, 153-160. Irwin, M., Caldwell, C., Smith, T.L., Brown, S., Schuckit, M.A., aand Gillin, J.C. (1990) Major depressive disorder, alcoholism, and reduced natural killer cell cytotoxicity: role of severity of depressive symptoms and alcohol consumption. Arch. Gen. Psychiatry 47, 713-719. Itwin, M., Daniels, M., Smith, T.L., Bloom, E. and Weiner, H. (1987a) Impaired natural killer cell activity during bereavement. Brain Behav. Immun. 1, 98-104. Irwin, M., Daniels, M. and Weiner, H. (1987b) Immune and neuroendocrine changes during bereavement. Psychiatr. Clin. North America 10, 449-465. Irwin, M., Smith, T.L. and Gillin, J.C. (1987~) Low natural killer cytotoxicity in major depression. Life Sci. 41, 21272133. Jones, J.M., Yeralan, O., Hines, G., Maher, M., Roberts, D.W. and Benson, R.W. (1990) Effects of lithium and rubidium on immune responses of rats. Toxicol. Lett. 52, 163-168. Kronfol, Z., Hamdan-Allen, G. and Black, D.W. (1988) Fever and leukocytosis: physical manifestations of bipolar affective disorder. Prog. Neuro-Psychopharmacol. Biol. Psychiatr. 12, 887-891. Kronfol, Z. and House, J.D. (1988) Immune function in mania. Biol. Psychiatry 24, 341-343. Kronfol, Z., Turner, R., House, J.D. and Winokur, W.E. (1984) Elevated blood nueutrophil concentrations in mania. J. Clin. Psychiat. 47, 63-65. Kurman, C., Rubin, L. and Nelson, D. (1992) Soluble products of immune activation: soluble interleukin-2 receptor (SIL-2R, tat protein). In: N. Rose et al. (Eds.), Manual of Clinical Laboratory Immunology American Society for Microbiology, Washington, DC, pp. 256-260. Lazarus, J.H., McGregor, A.M., Ludgate, M., Darke, C., Creagh, F.M. and Kingswood, C.J. (1986) Effect of lithium carbonate therapy on thyroid immune status in manic depressive patients: a prospective study. J. Affect. Disorders, 11, 155-160.

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M.H. Rapaport /Journal

of Affective Disorders 32 (1994) 149-156

Maes, M., Bosmans, E., Suy, E., Vandervorst, C., DeJonckheere, C. and Raus, J. (1991) Depression-related disturbances in mitogen-induced lymphocyte responses and interleukin-lp and soluble interleukin-2 receptor production. Acta Psychiatr. Stand. 84, 379-386. McAllister, C.G., Rapaport, M.H., Pickar, D., Prodnuchny, T.A., Christison, G., Alphs, L.D. and Paul, S.M. (1989) Increased numbers of CDS+ B lymphocytes in schizophrenic patients. Arch. Gen. Psychiatry 46, 890-894. McAllister, C.G., Rapaport, M.H., Pickar, D. and Paul, SM. (1989) Effects of short-term administration of antipsychotic drugs on lymphocyte subsets in schizophrenic patients. Arch. Gen. Psychiatry, 46, 957-9.58. Muller, N., Ackenheil, M., Eckstein, R., Hofschuster, E. and Mempel, W. (1987) Reduced suppressor cell function in psychiatric patients. Ann. N.Y. Acad. Sci. 496, 686-90. O’Riordan, J.W., Kelleher, D., Williams, Y. and Bloomfield, F.J. (1986) Effect of Lithium therapy on inflammatory response. Inflammation 10, 49-57. Ozdemir, M.A., Sofuoglu, S., Tanrikulu, G., Aldanmaz, F., Esel, E. and Dundar, S. (1994) Lithium-induced hematologic changes in patients with bipolar affective disorder. Biol. Psychiatry, 35, 210-213. Paciotti, G.F., Baron, D., Licinio, J., Tamarkin, L., Wong, M.L., Gold, P.W., Altemus, M.E. and Rubinow, D. (1992) Novel enzyme immunoassays for the detection of cytokines interleukin-1 and interleukin-2 in the circulation of normal subjects: 24 hour profile. Prog. NeuroEndocrinImmunol. 5, 21-30. Rapaport, M.H., Torrey, E.F., McAllister, C.G., Nelson, D.L., Pickar, D. and Paul, S.M. (1993) Increased serum soluble interleukin-2 receptors in schizophrenic monozygotic twins. Eur. Arch. Psychiatry Clin. Neurosci., in press. Rapaport, M.H., McAllister, C.G., Kim, Y.S., Han, J.H., Pickar, D., Nelson, D.L., Kirch, D.G. and Paul, S.M. (1994) Increased serum soluble interleukin-2 receptors in Caucasian and Korean schizophrenic patients. Biol. Psychiatry 35, 56-60. Rapaport, M.H. and Stein, M.B. (1994) Serum cytokine and soluble interleukin-2 receptors in patients with panic disorder. Anxiety 1, 22-25.

Rapaport, M.H., Doran, A.R., Nelson, D., McAllister, C., Magliozzi, J.R. and Paul, S.M. (1991) Haloperidol and soluble interleukin-2 receptors. Biol. Psychiatry 30, 10631065. Rapaport, M.H., McAllister, C.G., Pickar, D., Nelson, D.L. and Paul, SM. (1989) Elevated levels of soluble interleukin 2 receptors in schizophrenia. Arch. Gen. Psychiatry 46, 291-292. Rubin, L.A. and Nelson, D.L. (1990) The soluble interleukin-2 receptor: biology, function and clinical application. Ann. Intern. Med. 113, 619-627. Schiffer, R.B., Wineman, N.M. and Weitkamp, L.R. (1986) Association between bipolar affective disorder and multiple sclerosis. Am. J. Psychiatry, 143, 94-95. Schleifer, S.J., Keller, SE., Camarino, M., Thornton, J.C. and Stein, M.M. (1983) Suppression of lymphocyte stimulation following bereavement. JAMA, 374-377. Schleifer, S., Keller, S., Meyerson, A., Raskin, J., Davis, K. and Stein, M. (1984) Lymphocyte function in major depressive disorder. Arch. Gen. Psychiatry 41, 484-486. Schleifer, S., Keller, S., Bond, R., Cohen, J. and Stein, M. (1989) Major depressive disorder and immunity, role of age, sex, severity and hospitalization. Arch. Gen. Psychiatry 46, 81-87. Sengar, D.P.S., Waters. B.G.H. and Dunne, J.V. (1982) Lymphocyte subpopulations and mitogenic responses of lymphocytes in manic depressive disorder. Biol. Psychiatry 17, 1017-1022. Solomon, G., Allansmith, M., McClellan, B. and Amkraut, A. (1969) Immunoglobulins in psychiatric patients. Arch. Gen. Psychiatry, 20, 272-277. Spitzer, R., Williams, J., Gibbon, M. and First, M. (1988) Instruction Manual for the Structured Clinical Interview for DSM III-R (SCID). New York, NY. Vrethem, M., Skogh, T., Berlin, G. and Ernerudh, J. (1992) Autoantibodies versus clinical symptoms in blood donors. J. Rheumatol. 19, 1919-1921. Wahlin, A., von Knorring, L. and Roos, G. (1984) Altered distribution of T lymphocyte subsets in lithium-treated patients. Neuropsychobiol. Med. 11, 243-246.