Autoantibodies to DNA in multicase families with schizophrenia

Antinuclear Autoantibodies in Health: Autoimmunity Is Not a Synonym of Autoimmune Disease

The incidence of autoimmune diseases is increasing. Antinuclear antibody (ANA) testing is a critical tool for their diagnosis. However, ANA prevalence in healthy persons has increased over the last decades, especially among young people. ANA in health occurs in low concentrations, with a prevalence up to 50% in some populations, which demands a cutoff revision. This review deals with the origin and probable physiological or compensatory function of ANA in health, according to the concept of immunological clearance, theory of autoimmune regulation of cell functions, and the concept of functional autoantibodies. Considering ANA titers ≤1:320 as a serological marker of autoimmune diseases seems inappropriate. The role of anti-DFS70/LEDGFp75 autoantibodies is highlighted as a possible anti-risk biomarker for autoimmune rheumatic disorders. ANA prevalence in health is different in various regions due to several underlying causes discussed in the review, all influencing additive combinations according to the concept of the mosaic of autoimmunity. Not only are titers, but also HEp-2 IFA) staining patterns, such as AC-2, important. Accepting autoantibodies as a kind of bioregulator, not only the upper, but also the lower borders of their normal range should be determined; not only their excess, but also a lack of them or "autoimmunodeficiency" could be the reason for disorders.

Natural Catalytic IgGs Hydrolyzing Histones in Schizophrenia: Are They the Link between Humoral Immunity and Inflammation?

Schizophrenia is known to be accompanied not only with an imbalance in the neurotransmitter systems but also with immune system dysregulation and chronic low-grade inflammation. Extracellular histones and nucleosomes as damage-associated molecular patterns (DAMPs) trigger systemic inflammatory and toxic reactions by activating Toll-like receptors. In this work, we obtained the first evidence that polyclonal IgGs of patients with schizophrenia effectively hydrolyze five histones (H1, H2a, H2b, H3, and H4). Several strict criteria were used to demonstrate that histone-hydrolyzing activity is a property of the analyzed IgGs. The IgGs histone-hydrolyzing activity level, depending on the type of histone (H1–H4), was statistically significantly 6.1–20.2 times higher than that of conditionally healthy donors. The investigated biochemical properties (pH and metal ion dependences, kinetic characteristics) of these natural catalytic IgGs differed markedly from canonical proteases. It was previously established that the generation of natural catalytic antibodies is an early and clear sign of impaired humoral immunity. One cannot, however, exclude that histone-hydrolyzing antibodies may play a positive role in schizophrenia pathogenesis because histone removal from circulation or the inflamed area minimizes the inflammatory responses. Thus, it can be assumed that histone-hydrolyzing antibodies are a link between humoral immunity and inflammatory responses in schizophrenia.

The relationship between serum cytokine levels and degree of psychosis in patients with schizophrenia

Several observations indicate that cytokine concentrations might also relate to the severity of the psychosis. In this study we assessed whether inflammatory and anti-inflammatory cytokine concentrations are associated with the degree of the psychotic manifestations. A group of 41 patients with schizophrenia suffering from an acute psychosis leading to hospitalization in a psychiatric ward were assessed for the intensity of their psychotic manifestations by the PANSS score. Serum IL-2R, IL-6, IL-8, IL-10 were analyzed by commercial ELISA kits. These patients were compared to controls without schizophrenia. At the univariate analysis, statistically significant elevated levels of the cytokines IL-6, IL-2R and IL-8 were detected in the sera of the patients with schizophrenia compared to controls. At the multivariate analysis, statistically significance held only for IL-2R concentration. Furthermore, positive correlation was found between symptom severity as measured by the PANSS and IL-6 levels as well as IL-2R levels. In Conclusion, our data indicate that elevated serum concentrations of IL-6, IL-8 and IL-2R are associated with severe clinical symptoms measured by the total, general, negative and positive scores of the PANSS scale.

[Antibodies to native and denatured DNA in the serum of patients with schizophrenia depending on the clinical features of the disease]

OBJECTIVE

To study the correlations between the level of antibodies to native and denatured DNA and psychopathological symptoms and illness duration in patients with schizophrenia.

MATERIAL AND METHODS

The level of antibodies to native (double-stranded) DNA and denatured (single-stranded) DNA was studied in the serum of 50 patients with schizophrenia, including 12 patients with tardive dyskinesia (TD). The control group consisted of 30 people.

RESULTS

A significant twofold increase in antibodies to native DNA was detected in patients with TD. There was no correlation of the amount of antibodies to double-stranded DNA with the duration of disease and leading symptoms both between the groups of patients as well as in comparison with controls. A significant decrease in antibody levels to the denatured (single-stranded) DNA was found in schizophrenic patients compared to the control group (p=0.009). A significant decrease in the concentration of antibodies to single-stranded DNA in patients with increasing duration of the disease, as well as in patients with leading negative symptoms was revealed.

CONCLUSION

The results suggest that anti-DNAantibodies may not play a major role in the pathogenesis of schizophrenia.

Difference in inflammatory cytokine production by mononuclear cells from obese and non-obese schizophrenic patients

OBJECTIVE

Schizophrenic patients have an increased risk for obesity compared with the general population. Evidence suggests the existence of an inflammatory process in the etiology of both obesity and schizophrenia. Our study compares in vitro secretion of inflammatory cytokines by peripheral blood mononuclear cells (PBMC) obtained from obese and non-obese schizophrenic patients.

METHOD

Mononuclear cells were isolated from 20 obese (BMI >27) and 20 non-obese (BMI <24) schizophrenic in-patients. The levels of TNF-α, IL-1β, IL-6, IL-1ra, IL-10 or IL-2 and IFN-γ in the supernatants of stimulated PBMC, as well as leptin and adiponectin serum values were evaluated.

RESULTS

Peripheral blood mononuclear cells from patients in the obese group showed a significantly increased TNF-α and IL-1β production, whereas the release of IL-1ra was decreased as compared with the non-obese group. In the obese group, the serum concentration of leptin was significantly higher and that of adiponectin was significantly lower. The results of the remaining cytokines did not differ between the two groups.

CONCLUSION

Our study indicates the existence of a difference between obese and non-obese schizophrenic subjects as for inflammatory cytokine production and serum leptin and adiponectin levels, suggesting a 'subclinical inflammatory state' in obese schizophrenic patients that may contribute to a predisposition to inflammation and infections.

The prevalence of antinuclear antibodies in patients with schizophrenia spectrum disorders: results from a large cohort study

Background:

An increased prevalence of autoantibodies has been found in patients with schizophrenia, suggesting a role for autoimmunity in schizophrenia pathogenesis.

Methods:

We examined the presence of antinuclear antibodies (ANAs), with further determination of specific antibodies, in 368 patients with a schizophrenia spectrum disorder and 283 healthy controls.

Results:

No significant difference in prevalence of ANAs between patients (8%) and controls (11%) was found.

Conclusion:

We did not find an association between ANAs and schizophrenia spectrum disorders. We discuss potential reasons for the discrepancy with some previous studies, such as inclusion of patients using chlorpromazine, which can induce ANAs.

The use of proteomic biomarkers for improved diagnosis and stratification of schizophrenia patients

Schizophrenia is characterized by a wide spectrum of clinical manifestations, including strong effects on mood and behavior. Patients can also suffer from serious comorbidities including immune system or metabolic abnormalities. Recent advances using proteomic profiling approaches have increased our understanding of these molecular effects and have laid the groundwork for unraveling the heterogeneity of this broadly defined disease. These findings could lead to improved diagnosis and stratification of patients through identification of biochemically different disease subtypes and personalized medicine approaches. The inclusion of molecular signatures in psychiatry will be an important leap forward in providing more effective treatment of patients suffering from this debilitating disorder.

A systematic, quantitative review of blood autoantibodies in schizophrenia

OBJECTIVE

Schizophrenia is associated with immune system dysfunction, including an increased prevalence of autoimmune disorders and autoantibodies. We performed a systematic, quantitative review of self-reacting blood antibodies in patients with schizophrenia.

METHOD

We identified articles by searching PubMed, PsychInfo, and ISI, and the reference lists of identified studies.

RESULTS

Eighty-one of 111 studies identified met the inclusion criteria. There was a significant increased prevalence of positive titers for 20 different autoantibodies in patients with schizophrenia compared to controls. The prevalence of positive anti-cardiolipin IgG and NMDA receptor titers was also significantly increased in subjects with first-episode psychosis versus controls (p<0.01). Absolute titers for anti-cardiolipin IgG and IgM, and nerve growth factor were significantly increased in patients with schizophrenia compared to controls (p<0.02 for each).

CONCLUSION

Schizophrenia is associated with an increased prevalence of multiple autoantibodies, although there is marked study heterogeneity, and correlations between autoantibodies and clinical features are inconsistent. This area merits more research evaluation, especially controlling for potential confounding factors such as clinical status, age, genetic background, psychotropic medications, BMI, and smoking.

The TRIPS (Toll-like receptors in immuno-inflammatory pathogenesis) Hypothesis: a novel postulate to understand schizophrenia

Mounting evidence indicates that immune activation and/or immuno-inflammatory reactions during neurodevelopment apparently contribute to the pathogenesis and progression of schizophrenia. One of the important environmental factors that is known to trigger immune activation/inflammatory responses during early pregnancy is prenatal infection. Recent understanding from animal studies suggests that prenatal infection induced maternal immune activation (MIA)/inflammation in congruence with oxidative/nitrosative stress can lead to neurodevelopmental damage and behavioral abnormalities in the offspring. Although the underlying precise mechanistic processes of MIA/inflammation are yet to be completely elucidated, it is being increasingly recognized that Toll-like receptors (TLRs) that form the first line of defense against invading microorganisms could participate in the prenatal infection induced immune insults. Interestingly, some of the TLRs, especially TLR3 and TLR4 that modulate neurodevelopment, neuronal survival and neuronal plasticity by regulating the neuro-immune cross-talk in the developing and adult brain could also be affected by prenatal infection. Importantly, sustained activation of TLR3/TLR4 due to environmental factors including infection and stress has been found to generate excessive reactive oxygen species (ROS)/reactive nitrogen species (RNS) as well as pro-inflammatory mediators during embryogenesis, which result into neuronal damage by necrosis/apoptosis. In recent times, ROS/RNS and immuno-inflammatory mediators are being increasingly linked to progressive brain changes in schizophrenia. Although a significant role of TLR3/TLR4 in neurodegeneration is gaining certainty, their importance in establishing a causal link between prenatal infection and immuno-inflammatory, oxidative and nitrosative stress (IO&NS) responses and influence on adult presentation of schizophrenia is yet to be ascertained. We review here the current knowledge generated from the animal and human studies on the role of TLRs in schizophrenia and finally propose the "TRIPS Hypothesis" (Toll-like receptors in immuno-inflammatory pathogenesis) to elucidate the underlying mechanism(s) of TLR-mediated risk of schizophrenia. Considering the established role of TLR3 and TLR4 in antiviral and antibacterial responses respectively, we believe that in some cases of schizophrenia where IO&NS responses are evident, prenatal infection might lead to neuroprogressive changes in a TLR3/TLR4-dependent way.

Proteomic profiling in schizophrenia: enabling stratification for more effective treatment

Schizophrenia is a heterogeneous psychiatric disorder characterized by an array of clinical manifestations. Although the best known manifestations include serious effects on mood and behavior, patients can also display co-morbidities, including immune system or metabolic abnormalities. Thorough characterization of these conditions using proteomic profiling methods has increased our knowledge of these molecular differences and has helped to unravel the complexity and heterogeneity of this debilitating condition. This could lead to patient stratification through characterization of biochemically different subtypes of the disease. In addition, proteomic methods have recently been used for molecular characterization of the mechanism of action of antipsychotic medications in both preclinical models and patients. This has resulted in identification of molecular panels that show some promise for prediction of response or for monitoring treatment outcome. This review describes how proteomic profiling methods can impact the future of schizophrenia diagnosis and therapeutics, and facilitate personalized medicine approaches for more effective treatment management of schizophrenia patients.

Explorando o componente inflamatório da esquizofrenia

A esquizofrenia é uma doença heterogênea caracterizada por um conjunto de manifestações clínicas. Um grande número de estudos ao longo dos últimos 20 anos apontou para anormalidades no sistema imune em pacientes que sofrem dessa condição. Em adição, tem sido mostrado que a psicose e a disfunção cognitiva associadas com a esquizofrenia estão ligadas a doenças autoimunes. Aqui, revisamos a evidência que sugere que um status pró-inflamatório do sistema imune induz sintomas psicopatológicos e pode estar envolvido na fisiopatologia dessa principal doença mental. Também propomos que futuros estudos pré-clínicos e clínicos deveriam levar em conta tais causas predefinidas e o status do componente inflamatório. Estratificação de pacientes e estratégias de medicina personalizadas baseadas no direcionamento ao componente inflamatório da doença poderiam ajudar na redução de sintomas e da progressão da doença. Por fim, isso poderia levar a novos conceitos na identificação de alvos moleculares em esquizofrenia e estratégias de descoberta de drogas.

Expression of anti-cardiolipin antibodies and inflammatory associated factors in patients with schizophrenia

Numerous studies have implicated a connection between schizophrenia and autoimmune disorders. However, the precise relationship and underlying mechanism are still obscure. To further identify the association between autoimmune disorders and schizophrenia, the mRNA expressions of various cytokines and Toll-like receptors (TLRs) in monocytes are examined by using RT-PCR. Additionally, ELISA and zymography were performed to determine the anti-cardiolipin antibody (aCL) and MMP9 activity in serum form schizophrenic patients. Notably, significantly increased interleukin (IL)-6 and IL-10 mRNA were observed in schizophrenic patients, whereas significant reductions of TLR-3 and TLR-5 mRNA were detected. Moreover, significantly increased levels of aCL antibody and a higher frequency of positive-MMP9 activity were detected in serum from patients with schizophrenia. Meanwhile, no significant association was found between each of the medications and aCL activity. These findings demonstrated autoimmune-related phenomena in schizophrenic patients and further suggested a connection between schizophrenia and autoimmune disorders.

Autoimmune pathology accounts for common manifestations in a wide range of neuro-psychiatric disorders: the olfactory and immune system interrelationship

Smell has traditionally been considered a less important sense when compared to sight or hearing, but recent research has unraveled important features inherent to the sense of smell. Once considered just a chemical sensor for sampling the environment, data from animal models and human studies currently imply numerous and complex effects of smell on behavior, mood, and on the immune response. In this review we discuss a possible inter-relationship between olfactory impairment, autoimmunity and neurological/psychiatric symptoms in several diseases affecting the central nervous system (CNS) such as Parkinson, Alzheimer's disease, autism, schizophrenia, multiple sclerosis and neuropsychiatric lupus erythematosus. We suggest that common manifestations are not mere coincidences. Current data from animal models show that neuropsychiatric manifestations are intimately associated with smell impairment, and autoimmune dysregulation, via autoantibodies (anti-NMDAR, anti-ribosomal P) or other mechanisms. From clues of pathological manifestations, we propose a novel approach to the understanding of the interactions between the CNS, the smell and the immune system.

The ultrastructure of lymphocytes in schizophrenia

OBJECTIVE

Replicated abnormalities in schizophrenia include decreased cellular immunity. The aim of the study was to verify whether there are some abnormalities in the ultrastructure of lymphocytes in drug-free schizophrenic patients.

METHOD

Fifty-nine in-patients with paranoid schizophrenia (DSM-IV 295.30) and 31 normal controls were used. Psychosis severity was assessed by the PANSS psychotic cluster. Electron microscopy and morphometric methods were applied to estimate the frequency and ultrastructural parameters of small, large, large activated lymphocytes (LAL) (containing 10 and more mitochondria) and of atypical lymphocytes (lymphoblasts, LB).

RESULTS

The frequency of small lymphocytes in schizophrenic patients was lower and that of large lymphocytes, LAL and LB was higher than in controls (all p= < 0.01). The volume density (Vv) of mitochondria in LAL in individuals with schizophrenia was lower than in controls (p<0.05), correlated negatively with the frequency of LB, Vv and number of lysosomes in LB (all p<0.01) and with the psychosis severity (p<0.05). In schizophrenic patients a trend towards positive correlations between the frequency of LB and psychosis severity were found (p<0.07).

CONCLUSION

The data suggest that the excess of LB in schizophrenic patients is associated with the dysfunction of energy metabolism in LAL, and these abnormalities are related to schizophrenia.

Reduced anticardiolipin antibodies in first episode and chronic schizophrenia

The objective of this study was to measure anticardiolipin antibodies (aCL) in major psychiatric diseases. In Experiment 1, 96 subjects were evaluated: 20 first episode schizophrenia patients, [SCZ1] 20 chronic schizophrenia patients in acute exacerbation [SCZ2], l9 bipolar patients, 20 schizoeffective patients and 17 healthy age matched controls. In Experiment 2, 97 subjects were studied: 20 first episode schizophrenia patients [SCZ1], 60 chronic schizophrenia patients in acute exacerbation [SCZ2] and 17 healthy matched controls. Diagnosis was performed according to DSM-IV. Serum samples were tested for aCL in parallel by enzyme-linked immunosorbent assay in the presence of bovine serum. Five positive control samples with high levels of aCL were run in parallel. Background binding to wells uncoated with cardiolipin (CL) was also measured. In Experiment 1, aCL levels were similar in the control, bipolar and schizoeffective groups. In contrast, aCL levels in the SCZ1 and SCZ2 groups were significantly lower than in controls. In Experiment 2, Significantly lower levels of aCL antibodies were found in all schizophrenic patients versus controls. Interestingly, background levels in both experiments were higher in the schizophrenic groups than in controls. Serum aCL levels are lower in schizophrenic patients, and especially in first episode cases, than in controls. One possible explanation for the lower levels of aCL in schizophrenic patients is the consumption of these antibodies in the acute phase and exacerbation of the disease. The higher background levels in schizophrenic patients may indicate a high level of antibodies to some serum component in schizophrenic patients that is still unclear and needs further elucidation.

Schizophrenia, autoimmunity and immune system dysregulation: A comprehensive model updated and revisited

Recent investigation suggests a strong relationship between immunological effects and the pathophysiology of schizophrenia. Two prevalent approaches exist to this association. First, is more empirical a-priori research investigating immunological changes prevalent in schizophrenia and the second approach is more hypothesis-driven with analysis of immunological changes in schizophrenia based on known irregularities of the illness. The former approach is based upon three predominant lines of investigation including observations of a diffuse non-specific overactivation of the immunological response system, of a T-helper cell type 1 immune activation and of a T-helper cell type 2 immune activation in subgroups of schizophrenia patients. These last two theories suggest that a subgroup of patients with schizophrenia may demonstrate features of an autoimmune process, a theory supported by a growing database of investigation. The latter approach notes that many observations of immune dysregulation in schizophrenia overlap with central etiopathophysiological mechanisms as well as with clinical manifestations of the illness. Immunotherapy offers the opportunity to modify or re-balance the immune system and may become useful in management of the illness. Given that autoimmune mechanisms could interrupt neurotransmission, any process interfering with this disruption including therapeutic antibodies to involved cytokines, or with various other natural autoantibodies or immune system regulators, may become useful in the augmentative management of the illness.

Immune dysregulation and self‐reactivity in schizophrenia: Do some cases of schizophrenia have an autoimmune basis?

Schizophrenia affects 1% of the world's population, but its cause remains obscure. Numerous theories have been proposed regarding the cause of schizophrenia, ranging from developmental or neurodegenerative processes or neurotransmitter abnormalities to infectious or autoimmune processes. In this review, findings suggestive of immune dysregulation and reactivity to self in patients with schizophrenia are examined with reference to criteria for defining whether or not a human disease is autoimmune in origin. Associations with other autoimmune diseases and particular MHC haplotypes, increased serum levels of autoantibodies, and in vivo and in vitro replication of some of the functional and ultrastructural abnormalities of schizophrenia by transfer of autoantibodies from the sera of patients with schizophrenia suggest that, in some patients at least, autoimmune mechanisms could play a role in the development of disease. Recent findings regarding specific autoimmune responses directed against neurotransmitter receptors in the brain in patients with schizophrenia will also be reviewed.

Overproduction of neutrophil radical oxygen species correlates with negative symptoms in schizophrenic patients: parallel studies on neutrophil chemotaxis, superoxide production and bactericidal activity

Defective neutrophil function in schizophrenic patients has recently been reported. There are several lines of evidence to support the contribution of oxygen free radicals in schizophrenia, including increased lipid peroxidation, fatty acids and alterations in blood levels of anti-oxidant enzymes. Eighteen schizophrenic patients (DSM-IV) and 15 healthy controls were studied. Neutrophil chemotaxis, superoxide production and bactericidal activity were investigated. A statistically significant increase of superoxide anion release was found in schizophrenic patients compared with controls (mean+/-S.E.M., patients: 6.89+/-0.30 nmol O2-/10(6) cells/min, controls: 5.13+/-0.55 nmol O2-/10(6) cells/min). Moreover, a significant positive correlation between superoxide production and negative symptoms as assessed by the Positive and Negative Syndrome Scale was demonstrated. No differences were detected in chemotaxis and phagocytosis between schizophrenic patients and healthy controls. The present findings of a positive correlation between superoxide generation and negative symptoms in schizophrenic patients support the hypothesis that superoxide anion may participate in the pathogenesis of schizophrenia, as an excess of free radicals could contribute to the deterioration phase of the disease. Further studies are required to establish the role of oxidative stress in the ethiopathogenesis of schizophrenia.

Autoantibodies to serotonin in serum of patients with psychiatric disorders

Antibodies to serotonin in serum were investigated by ELISA in patients with paranoid schizophrenia (N=27), schizoaffective psychosis (N=38), depression (N=67), Alzheimer's disease (N=21), chronic alcoholism (N=43), rheumatoid arthritis (N=25), and multiple sclerosis (N=16), and in healthy volunteers (N=60). Increased antibody reactivity to serotonin was found in schizoaffective psychosis, chronic alcoholism, and rheumatoid arthritis. Decreased antibody reactivity to serotonin was found in multiple sclerosis and depression. These anti-serotonin antibodies belong to the class of so-called natural autoantibodies. Alterations of these natural autoantibodies could indicate a disturbance to the immune system. It is possible that these antibodies could also influence receptor function. Autoantibodies to neurotransmitters in a wide spectrum of psychiatric disorders have not previously been reported.

Review of immunological and immunopathological findings in schizophrenia

The involvement of immunological and immunopathological mechanisms in the etiopathogenesis of schizophrenia has been a matter of research, with recently increasing effort. This article reviews the findings focusing on postmortem neuropathology, the blood-brain barrier, antibodies, acute phase proteins, immunocompetent cells, and activation markers of immunocompetent cells. Evidence for the two primarily postulated hypotheses (the infectious hypothesis and the autoimmune hypothesis) is critically discussed. On the basis of the findings, perspectives for future research are outlined aiming at a precise and consequent strategy to elucidate a potential involvement of immune mechanisms in the etiopathogenesis of schizophrenia.

Electron microscopy of oligodendroglia in severe mental illness

Qualitative electron microscopy was performed to verify whether brain pathology in schizophrenia and bipolar disorder is associated with alterations of oligodendroglial cells and myelinated fibers. Ultrastructural signs of apoptosis and necrosis of oligodendroglial cells were found in the prefrontal area 10 and the caudate nucleus in both schizophrenia and bipolar disorder. Damage of myelin sheath lamellae, with the formation of concentric lamellar bodies, were detected in both brain structures in schizophrenia. There was also a significant decrease in the area of the nucleus and the volume density of mitochondria in oligodendrogliocytes in the caudate nucleus and in the prefrontal cortex in schizophrenia, as compared to normal controls. Volume density of heterochromatin was significantly increased (+14%) in the caudate nucleus in schizophrenia. The density of concentric lamellar bodies (as an indicator of damage of myelinated fibers) was dramatically increased (4.5-fold) in the caudate nucleus in schizophrenia, as compared to controls, and was positively correlated with volume density of heterochromatin. Multiple regression analysis and analysis of covariance demonstrated that these changes could not be explained by the effects of postmortem delay, age, neuroleptic medication, or gender. Pathology of oligodendroglia might be an essential feature of severe mental disorders.

Immune related genetic polymorphisms and schizophrenia among the Chinese

Genetic association studies were conducted among two independent cohorts of Chinese ethnicity. The samples consisted of cases and unrelated controls, ascertained from Guangzhou, China, and Singapore. The studies were prompted by our earlier report of an association between schizophrenia and HLA DQB1 alleles (HLA DQB1*0602 and HLA DQB1*0303) in the Singapore sample. Polymorphisms of HLA DQB1 and flanking markers on chromosome 6p21.3 were investigated in the first part of the study. A significant negative association with HLA DQB1*0402 was detected in the Guangzhou sample (Odds ratio, OR 0.26, 95% confidence intervals, CI 0.1, 0.6; p < 0.02, corrected for multiple comparisons). Additional analysis of the Guangzhou and Singapore samples revealed associations at three other anonymous markers flanking HLA DQB1. In the second part of the study, three polymorphisms at the Interleukin-1 gene cluster (IL-1, chromosome 2q13-q21) were investigated in both cohorts, since associations with schizophrenia have been reported in another sample. Persuasive evidence for an association at IL-1 was not detected in either sample. Our results suggest a susceptibility locus for schizophrenia in the HLA region among the Chinese, but further clarification is necessary.

Elevation of CD5+ B lymphocytes in schizophrenia

BACKGROUND

A variety of immunologic alterations have been observed in patients with schizophrenia. These findings have lent support to theories that autoimmune mechanisms may be important in some patients with the illness. The CD5+ B lymphocyte, a B-cell subset associated with autoimmune disease, has been the subject of two previously published studies yielding disparate results.

METHODS

In this study, we used immunofluorescent flow cytometry to measure CD5+ B cells, total B and T cells, and CD4 and CD8 subsets in patients with schizophrenia and in normal control subjects.

RESULTS

A significantly higher percentage of patients with schizophrenia, relative to normal control subjects, exhibited an elevated level of CD5+ B cells (27.6% vs 6.7%). Antipsychotic withdrawal had no effect on CD5+ B-cell levels, suggesting that medication effects were not the cause of this difference. No other studied lymphocyte subsets differed between the two groups.

CONCLUSIONS

A subset of patients with schizophrenia have elevated levels of CD5+ B cells. This finding replicates an earlier study by another group and provides further evidence suggestive of autoimmune manifestations in schizophrenia.

Leukocyte differentials predict short-term clinical outcome following antipsychotic treatment in schizophrenia

BACKGROUND

The majority of patients with schizophrenia and many of their unaffected siblings exhibit a relative granulocytosis and lymphopenia. To characterize these abnormalities better, we examined leukocyte differentials and organ nonspecific autoantibodies in relationship to intake phenomenology and short-term clinical outcome.

METHODS

We studied patients with schizophrenia (n = 81) and their siblings (n = 18). At intake assessment, about one-half of the probands (n = 38) were neurolepticnaive first-episode patients; the remainder were medication-free for at least 2 weeks. Hematologic indices were obtained at intake assessment, and psychiatric symptomatology was assessed at baseline and following 6 months of clinically determined treatment.

RESULTS

A relative granulocytosis and lymphopenia prospectively predicted poorer recovery in positive, but not negative, symptoms after 6 months of antipsychotic treatment. Abnormal leukocyte proportions were specific to patients who presented with clinically significant positive symptomatology at intake. In contrast, clinically significant negative symptoms were only evident in a small subgroup of patients who were positive for antinuclear autoantibodies and/or rheumatoid factor.

CONCLUSIONS

Future research should further test the hypothesis that a relative granulocytosis and lymphopenia reflect genetic loading for the pathophysiologic determinants of positive symptoms. Future research also should determine the etiologic significance of organ nonspecific autoimmunity in predominantly negative symptom schizophrenia.

Antibodies to neuroblastoma cell line proteins in patients with schizophrenia

The presence of antibodies against neural antigens was investigated in the serum of patients with schizophrenia, major depression and normal controls. Different immunological abnormalities, humoral and cellular, were reported in schizophrenia and major depression. The pathogenesis of schizophrenia is multifactorial. An autoimmune mechanism was suggested as a possible factor. We tested the serum of 26 patients with schizophrenia, eight patients with major depression and 22 normal controls. The serum samples were tested for antibody binding to protein extracts of IMR-32 neuroblastma cell line using Western blot analysis. Immunoglobulins of eight patients with schizophrenia (30.71%) reacted with a protein of 80-85 kDa. Serum samples from subjects of other groups did not react with this protein. Sera of all patients with major depression but one, and all normal controls reacted with HSP 60 kDa to different extent. This is an apparent discrepancy with the findings of Kilidireas et al. [Kilidireas, K., Latov, N., Strauss, D.H., Gorig, A.D., Hashim, G.A., Gorman, J.M., Sadig, S.A., 1992. Antibodies to the human 60 kDa heat shock protein in patients with schizophrenia. Lancet 340, 569-572.] who demonstrated the presence of antibodies against HSP 60 kDa in 44% of patients with schizophrenia tested and 8% of normal subjects. HSP 60 kDa is an antigen of many pathogens and antibodies against it might be a result of an infection and cannot be a good indicator for an autoimmune process. The presence of antibodies against a protein of 80-85 kDa should be investigated as a possible specific indicator.

Neurobehavioral alterations in autoimmune mice

Inbred MRL, NZB and BXSB strains of mice spontaneously develop a systemic, lupus-like autoimmune disease. The progress of autoimmunity is accompanied with a cascade of behavioral changes, most consistently observed in tasks reflective of emotional reactivity and the two-way avoidance learning task. Given the possibility that behavioral alterations may reflect a detrimental consequence of autoimmune-inflammatory processes and/or an adaptive response to chronic malaise, they are tentatively labeled as autoimmunity-associated behavioral syndrome (AABS). It is hypothesized that neuroactive immune factors (pro-inflammatory cytokines, brain-reactive antibodies) together with endocrine mediators (corticotropin-releasing factor, glucocorticoids) participate in the etiology of AABS. Since AABS develops natively, and has a considerable face and predictive validity, and since the principal pathway to autoimmunity is known, AABS may be a useful model for the study of CNS involvement in human autoimmune diseases and by extension, for testing autoimmune hypotheses of several mental disorders (major depression, schizophrenia, Alzheimer's disease, autism and AIDS-related dementia).

Leukocytes and organ-nonspecific autoantibodies in schizophrenics and their siblings: markers of vulnerability or disease?

To determine whether leukocyte counts and organ-nonspecific autoantibodies mark familial vulnerability for schizophrenia and/or the disease itself, we examined 92 patients with schizophrenia and 94 unrelated, demographically balanced, healthy individuals. In addition, for 19 of the probands, one of their nonschizophrenia, full siblings also was recruited. At the time of the blood draw, most probands (87%) had been free of medications for a minimum of 2 weeks and about half were neuroleptic-naive, first-episode patients. Results indicate that a relative lymphopenia in the context of a relative granulocytosis appears to mark familial vulnerability for schizophrenia, whereas an absolute monocytosis appears to mark spectrum manifestations of the clinical phenotype. The former observation is consistent with the hypothesis that the etiology of schizophrenia is immunologically mediated, whereas the latter is consistent with emerging evidence that an inflammatory process is associated with the expression of the disorder. Neither antinuclear antibody nor rheumatoid factor emerged as liability or disease markers.

Anticardiolipin antibodies are elevated in drug-free, multiply affected families with schizophrenia

The objective of this study was to measure anticardiolipin antibodies in patients and healthy relatives in multicase families with schizophrenia. Twenty-eight (28) multicase families with schizophrenia were examined. One hundred three drug-free patients and 66 first-degree relatives consented to evaluation by DSM-III-R criteria. Criteria for patient definition included the following: age > or = 16, a confirmed hospital diagnosis of schizophrenia, knowledge of biological parents, and consent to participate. Additional data were drawn from family history and medical records. Serum samples were tested separately for IgG and IgM anticardiolipin by enzyme-linked immunosorbent assay (ELISA) and designated positive/negative by comparison to the reactivity of an age-matched control group. IgG anticardiolipin antibodies were significantly more common in both patients and relatives compared to controls. IgM anticardiolipin antibodies were significantly more common in patients. In 75% of families at least one member was anticardiolipin positive and this positivity correlated with patient positivity. The relevance of anticardiolipin antibodies in both patients and healthy relatives of some multicase families to the pathogenesis of schizophrenia is discussed.