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Background The origin of suicidal behaviour is multifactorial including genetic, neurobiological and psychosocial correlates. Although there is no doubt that serotonin has a central role, the overall genetic findings with candidate genes of the serotonergic pathway are relatively inconsistent and suggests that other, yet unidentified, genes and gene products are also contributing to the vulnerability of suicidality. Proteomics is a powerful method to investigate modifications in protein expression. Methods We performed comparative proteomic analysis with prefrontal cortex tissues of 17 suicide victims and 9 controls. Results Applying two dimensional gel electrophoresis and image analysis we detected five protein spots to differ significantly in intensities between both groups. Three of them appeared only in suicide victims and could be identified by means of MALDI-TOF-MS analysis and protein database search as α crystallin chain B (CRYAB), glial fibrillary acidic protein (GFAP) and manganese superoxide dismutase (SOD2). CRYAB belongs to the low molecular heat shock proteins and GFAP is known as a marker of astrocytic activation in gliosis. SOD2 is a major antioxidant enzyme protecting cells against oxidative injury. Two further spots revealed higher intensities in the control group but had no unambiguous protein to match. Conclusions Our findings suggest that proteins, being involved in glial function, neurodegeneration and oxidative stress neuronal injury, might also have an impact upon the neurobiological cascade leading to suicidality. As animal data provide evidence for an up-regulation of GFAP synthesis in astrocytes due to alterations in 5-HT levels, similar mechanisms of interaction might also be relevant in humans.

Dysregulation of brain serotonin transmission is an important contributing factor in many psychiatric disorders. Tryptophan hydroxylase (TPH), the rate limiting enzyme in the biosynthesis of serotonin plays a major role as candidate gene in several psychiatric disorders. Recently, a second TPH isoform (TPH2) was identified in mice which was exclusively expressed in the brain. Due to the lack of data about its anatomic expression in humans we performed a mRNA expression analysis comparing TPH1 and TPH2 mRNA in several regions of the human brain (cortex, thalamus, hypothalamus, hippocampus, amygdala, cerebellum and raphe nuclei). The study was performed with post-mortem specimens obtained from eight individuals with sudden deaths, not directly involving CNS diseases. Our results demonstrate that the mRNA of both genes is expressed in each investigated brain region with variations between the brain areas, as well as between the particular genes. The major finding of this study was the high expression level of TPH2 mRNA in the raphe nuclei (∼4-fold more abundant than that of TPH1). The raphe nuclei showed the highest TPH2 mRNA levels at all, compared to the other regions (7-fold higher levels on average). To our knowledge, this is the fist study which demonstrates the localization of TPH1 and TPH2 mRNA in different regions of the human brain. Our findings provide further support for a duality of the serotonergic system and may open up new research strategies for the analysis of the repeatedly observed disturbances in the serotonergic system in patients suffering from several psychiatric disorders.

In 29 adults with attention deficit hyperactivity disorder (ADHD) striatal dopamine transporter (DAT) availability was assessed by [(99m)Tc]TRODAT-1 SPECT and correlated with 3' VNTR polymorphism of the DAT gene on chromosome 5p15.3. Seventeen patients showed homozygosity for the 10-repeat allele, two homozygosity of the 9 allele and 10 were heterozygous (9-10). No statistically significant difference in DAT availability was found between patients with 10-10 carriers (DAT 1.28 +/- 0.34) and with at least one 9 allele (DAT 1.31 +/- 0.27); when smokers were excluded, DAT availability was 1.38 +/- 0.28 in the 10-10 carriers (n = 12) and 1.42 +/- 0.19 in the 9-10 and 9-9 carriers (n = 7). In conclusion, no higher striatal DAT was found in patients with homozygosity of the 10 allele of the DAT gene in this study. These results differ from a study in 11 Korean children with ADHD, in which 10-10 carriers showed higher DAT availability in [(123)I]IPT SPECT. Discrepancies may be explained by differences in patient's age, ethnical differences, different imaging techniques or the limited number of patients included in both studies.

Most females with seasonal affective disorder (SAD) exhibit atypical vegetative symptoms such as overeating, and weight gain when depressed. The serotonin 2C receptor (5-HT 2C ) plays a key role in control of appetite and satiety. A 5-HT 2C Cys23Ser substitution, coded for by a single nucleotide polymorphism (Cys23Ser) within the 5-HT 2C gene, has been shown to influence 5-HT 2C function. We hypothesized that Cys23Ser influences weight regulation in females with SAD. Two independent samples from Austria (162 females with SAD, 119 controls), and Canada (90 females with SAD, 42 controls) were genotyped for Cys23Ser. Influence on weight regulation was analyzed within patients with atypical features. In Austrians, genotype distribution differed between patients and controls ( p = 0.044) and Cys23Ser was associated with weight ( p = 0.039), body mass index (BMI; p = 0.038), and seasonal appetite change ( p = 0.031). All values were highest in Cys/Cys, intermediate in Cys/Ser, and lowest in Ser/Ser carriers. In Canadian patients, Cys23Ser was associated with minimum lifetime BMI ( p = 0.046), with lowest values in Ser/Ser carriers. Our data provide evidence that Cys23Ser mediates severity of weight regulation disturbances in females with SAD, and the gene-dose effect-like differences suggest a direct functional role of Cys23Ser in the behavioral regulation of body weight.

In this study, we investigated whether availability of striatal dopamine transporter (DAT) may have an influence on the response of adult patients with attention deficit hyperactivity disorder (ADHD) on methylphenidate (MPH). In 18 non-smoking and non-medicated adult patients with ADHD, availability of DAT was measured with [(99m)Tc] TRODAT-1 SPECT. Then, the patients received methylphenidate (MPH), individually titrated up to 60 mg per day. Ten weeks later, clinical improvement was rated by Clinical Global Impressions scale. In all, 6 patients were classified as non-responders, and 12 responded to MPH. From the non-responders, 5 presented with a DAT availability below that of normal controls of the same age, whereas in the group of responders all patients had elevated DAT availability. There was a significant negative correlation between values for global clinical improvement and striatal DAT availability. In conclusion, ADHD patients with low DAT availability seem not to respond to therapy with MPH.

Neuropathic pain and fibromyalgia are prevalent diseases which have major consequences on healthcare resources and the individual. From the clinical point of view neuropathic pains represent a heterogeneous group of aetiologically different diseases ranging from cancer to diabetes. Patients with fibromyalgia also display clinical features common in neuropathic pain suggesting that there might be some overlap. The mechanisms responsible for symptoms and signs in both diseases are still unknown. Recently, there have been numerous reports of various pharmacological treatments of neuropathic pain and fibromyalgia with often disappointing results. Most of the studies were of short duration, had high attrition rates, and displayed other methodological problems. Some compounds had high rates of adverse effects which makes it often difficult for the patients to tolerate the treatment, especially in the long-term. At present, the best options for medication treatment are tricyclic antidepressants in lower dosage than usual in psychiatric disorders and a wide range of anticonvulsants. Opioids are sometimes recommended but have been found to have minor efficacy. Recently, there have been more controlled trials, which are reported here if they had been published between 2002 and 2004. Various compounds have been tested in different studies. Treatment of fibromyalgia, which has many features in common with depressive symptoms, became the focus of interest. New promising studies with dual serotonin-norepinephrine reuptake inhibitors (duloxetine and milnacipram) and a newer antiepileptic drug (pregabalin) are in progress. Future research will have to apply new approaches (eg, using a mechanism based classification of neuropathic pain and carrying out studies in populations with the same symptom but not necessarily the same disease) in order to find effective treatments for these common and often debilitating diseases.

Objectives: We have previously reported reduced serum levels of soluble intercellular adhesion molecule-1 (sICAM-1) in schizophrenic patients. A single-nucleotide polymorphism (SNP) of the ICAM-1 gene was described at position 241. The G→A SNP results in a nonsynonymous amino acid exchange of the ICAM-1 protein, and the A allele was shown to be also associated with several immunological disorders like rheumatoid arthritis. Methods: We investigated 70 schizophrenic patients and 128 unrelated healthy control persons regarding the relationship between the serum levels of sICAM-1 and the ICAM-1 G214A polymorphism. Results: We were able to replicate our previous finding of reduced sICAM-1 levels in schizophrenia. Healthy control persons carrying the polymorphic A allele showed markedly lower sICAM-1 serum levels than carriers of the homozygous GG wild type (p < 0.004). In contrast, no significant difference in the sICAM-1 serum levels were seen regarding the G241A genotype distribution in schizophrenic patients. Conclusion: We hypothesize that the biochemical effect of the G241A SNP is masked in schizophrenic patients, indicating a disease-related mechanism leading to reduced levels of sICAM-1 in schizophrenia.

Interferon-alpha (IFN-alpha) treatment is frequently complicated by symptoms of depression. The mechanism by which peripherally administered IFN-alpha enters and modulates the central nervous system remains unclear. The cell adhesion molecule ICAM-1 is involved in the regulation of blood-brain barrier (BBB) permeability. ICAM-1 expression was shown to increase during IFN-alpha treatment and recently the expression of ICAM-1 on vascular endothelial cells in the brain was found to be correlated with the development of depression. We therefore hypothesized that soluble ICAM-1 may be involved in the development of IFN-alpha associated depression. In a prospective study, serum levels of soluble ICAM-1 (double sandwich ELISA test) and symptoms of depression (SDS) were measured in 48 patients with malignant melanoma before and during adjuvant IFN-alpha treatment. Both, depression scores and the serum levels of sICAM-1 significantly increased after three months of IFN-alpha treatment compared to baseline levels (p.001). Patients who developed depression (SDS-index scoresor = 50) after three months of treatment had higher sICAM-1 levels compared to non-depressed patients. Furthermore, sICAM-1 levels were positively correlated with SDS values (r = .367, p = .018). Our data provides evidence for an association between the induction of sICAM-1 and the development of symptoms of depression during IFN-alpha treatment, possibly by enhancing BBB-permeability.

Background Tryptophan hydroxylase, the rate-limiting enzyme in the biosynthesis of serotonin, represents a major candidate in numerous genetic association analyses of suicidal behavior; however, the results are so far inconclusive. Recently, a second tryptophan hydroxylase isoform (TPH2) was identified in mice, which was exclusively present in the brain. In a previous postmortem study of our own group, we could demonstrate that TPH2 is also expressed in the human brain but not in peripheral tissues. Methods We performed single nucleotide polymorphisms, haplotypes, and linkage disequilibrium studies on 263 suicide victims and 266 healthy control subjects with 10 single nucleotide polymorphisms in the TPH2 gene. Results Significant association was detected between one single nucleotide polymorphism ( p = .004, global p = .01) and suicide. Additionally, haplotype analysis also produced support for association ( p p = .0001). Conclusions This is the first report about an association between TPH2 gene polymorphisms and completed suicide. Our findings provide evidence for an involvement of genetic variants in the TPH2 gene in suicidal behavior. These results might open up new research strategies for the analysis of the observed disturbances in the serotonergic system in several other psychiatric disorders.

The pathophysiological mechanisms, as well as the molecular loci of antidepressant drug action have not yet been established, but recent models proposed that several adaptive mechanisms in signal transduction cascades beyond the receptor and reuptake systems are involved in antidepressant action and play an important role in the etiology of affective disorders. In this context, the dysbindin gene (dystrobrevin-binding-protein 1, DTNBP1), which was recently reported to be associated with schizophrenia seems to be an interesting candidate gene for affective disorders. Dysbindin is widely expressed in the human brain and binds to the dystrophin-associated protein complex (DPC) which appears to be involved in signal transduction pathways, which have been repeatedly investigated and described as altered or disturbed in affective disorders [McLeod et al. [2003: Psychopharmacol Bull 35:24-41]; Brambilla et al. [2003: Mol Psychiatry 8:721-737]]. Therefore, we investigated whether five SNPs in the dysbindin gene could be susceptibility factors in the ethiology of major depression or for the response to antidepressant treatment in a sample of 293 patients compared to 220 healthy controls. Applying single SNP evaluation, as well as haplotype analysis we could not detect an association between the dysbindin polymorphisms and major depression or the response to antidepressant treatment. In conclusion, our results suggest that SNPs in the dysbindin gene are unlikely to play a major role in the pathophysiology of major depression or are in linkage disequilibrium (LD) with a neighboring mutation or gene. Further analysis are needed to confirm these results.

The neurotransmitter serotonin (5-hydroxytryptamine, 5-HT) has been implicated in numerous human disorders. Dysfunction of serotonergic neurotransmission is thought to play a major role in the pathophysiology of the fibromyalgia syndrome (FMS) which is characterised by non-restorative sleep and severe pain. In our study, both serotonin receptor subunit genes, HTR3A and HTR3B, have been investigated for sequence variations in FMS patients in order to reveal a possible involvement in the aetiology of FMS. We examined DNA samples from 48 patients with FMS representing sporadic cases by single-strand conformation polymorphism (SSCP) and denaturing high-performance liquid chromatography (dHPLC) analysis, sequenced samples with conspicuous patterns and performed statistical calculations. HTR3A mutational analysis revealed one novel as well as five known sequence variations. Investigating HTR3B, we detected seven formerly described mutations and one novel sequence variant. Statistical computation rated all variants as probably non-disease-related polymorphisms. Nevertheless, one might speculate about an effect of the respective sequence variants on the severity of the disease. Sequence variants of the serotonin receptor subunit genes HTR3A and HTR3B indicate no obvious significance in the aetiology of fibromyalgia, yet they represent the basis for future studies on their pharmacogenetic relevance.

Tryptophan hydroxylase (TPH), being the rate-limiting enzyme in the biosynthesis of serotonin plays a major role as candidate gene in several psychiatric disorders. Recently, a second TPH isoform (TPH2) was identified in mice, which was exclusively present in the brain. In a previous post-mortem study of our own group, we could demonstrate that TPH2 is also expressed in the human brain, but not in peripheral tissues. This is the first report of an association study between polymorphisms in the TPH2 gene and major depression (MD). We performed single-nucleotide polymorphism (SNP), haplotype and linkage disequlibrium studies on 300 depressed patients and 265 healthy controls with 10 SNPs in the TPH2 gene. Significant association was detected between one SNP (P=0.0012, global P=0.0051) and MD. Haplotype analysis produced additional support for association (P

Serotonergic mechanisms are thought to play an important role in the pathogenesis of seasonal affective disorder (SAD). The expression of the serotonin transporter (5-HTT) is regulated in part by an insertion/deletion polymorphism in the serotonin transporter gene promoter region (5-HTTLPR). The 5-HTTLPR short allele (s) has been associated with anxiety-related personality traits and depression, and one study observed an association between the 5-HTTLPR s-allele and SAD and the trait of seasonality. We genotyped 138 SAD patients and 146 healthy volunteers with low seasonality for 5-HTTLPR. No difference between patients and controls was found for genotype distribution and s-allele frequency. However, genotype distribution and allele frequencies were strongly associated with DSM-IV depression subtypes. Melancholic depression was associated with the 5-HTTLPR long (l) allele and atypical depression with the 5-HTTLPR s-allele (two-sided Fisher's exact test: genotype distribution: P=0.0038; allele frequencies: P=0.007). Our data are compatible with the hypothesis of a disease process that is not causally related to 5-HTTLPR, but involves 5-HT neurotransmission and 5-HTTLPR somewhere on its way to phenotypic disease expression.

Noradrenergic dysfunction has been implicated in the development of affective disorders. beta-adrenergic receptors (betaARs) mediate the response to norephinephrine, are coupled to the cAMP signaling cascade, supposed to be altered in their density and/or sensitivity in depression, and down regulated in several brain regions after long term treatment with different but not all antidepressants. A recently identified functional polymorphism in the beta(1)-adrenergic receptor (G1165C) leading to the amino acid variation Gly389Arg was associated with an enhanced coupling to the stimulatory G(s)-protein and increased adenylyl cyclase activation, disturbances which are often observed in affective disorders. Therefore, we investigated whether this beta(1)AR polymorphism is associated with major depression or with the response to antidepressant treatment in a sample of 259 patients compared to 206 healthy controls. Although we could not detect an association between the beta(1)AR polymorphism and major depression we found a tendency for a relation between CC homozygosity and a better and even faster response to antidepressant treatment in those patients, which were treated with antidepressants affecting directly or indirectly the beta(1)AR system (tricyclic antidepressants, noradrenergic and serotonergic specific agents, selective noradrenaline reuptake inhibitors) determined by the HAMD and CGI score (P = 0.05). However, after correction for multiple testing (Bonferroni) these results did not remain significant. Nevertheless, these findings suggest that the presence of the C allele might be an indicator for antidepressant treatment response.

The typical antipsychotic drugs like chlorpromazine and haloperidol were discovered by serendipity in the 1950s. A number of so-called “me too” drugs with similar chemical structures and modes of action were marketed in the subsequent years. The first atypical antipsychotic, clozapine, was an exception because it lacked some of the pharmacological properties of the typical antipsychotics related to the extrapyrimidal motor system. This unique feature of clozapine significantly broadened understanding of the mode of action of antipsychotics, and created new hypotheses for schizophrenia. Hypothesis-orientated development of new drugs was only recently initiated. Abnormalities of the immune system in schizophrenia are being increasingly discussed: shifts in the levels of T helper cells subsets 1 and 2 (Th1 and Th2) have been observed, and studies with risperidone and the cyclooxengenase (COX2) inhibitor celecoxib as an add-on therapy have provided very promising results. The glutamate N-methyl-D-aspartate (NMDA) receptors have also been investigated in relation to neuropathological abnormalities in prefrontal areas of the brain of patients with schizophrenia. This may lead to new technologies like artificial networks related to the glutamate NMDA receptor system. New molecular biological techniques used in pharmacogenomics and proteomics offer new and exciting directions for future drug developments.

Fibromyalgia (FM) is a prevalent syndrome with chronic pain and a hypothesized underlying disturbance of the tryptophan (TRP) metabolism. We performed a tryptophan depletion (TD) test in 17 FM patients and 17 controls. TRP, 5-hydroxyindoleacetic acid (5-HIAA), kynurenine (KYN), and interleukin-6 (IL-6) were measured. Additionally pain perception was monitored in the FM patients. FM patients and controls exhibited a decrease of TRP and KYN during TD. 5-HIAA levels also decreased in all controls and in 11 FM patients, but showed a marked increase in 6 FM patients. IL-6 significantly increased during TD in the patients, but not in the controls. Pain perception was not affected in the FM patients. These data demonstrate an altered TRP metabolism in a subgroup of FM patients, where the TD seems to activate 5-HT metabolism. Our findings may have diagnostic as well as therapeutic implications in the field of fibromyalgia.

Substance P (for “powder”), identified as a gut tachykinin in 1931 and involved in the control of multiple other autonomic functions, notably pain transmission, is the focus of intense fundamental and clinical psychiatric research as a central neurotransmitter, neuromodulator, and immunomodulator, along with sister neurokinins A and B (NKA and NKB), discovered in 1984. Substance P is widely distributed throughout the central nervous system, where if is often colocalized with serotonin, norepinephrine, and dopamine. Many neurokinin (NK) receptor antagonists and agonists have been synthesized and some clinically tested. A double-blind study of MK869, a selective NK1 receptor antagonist that blocks the action of substance P, showed significant activity versus placebo and fewer sexual side effects than paroxetine in outpatients with major depression and moderate anxiety. Substance P, which is degraded by the angiotensin-converting enzyme (ACE), may mediate modulation of therapeutic outcome in affective disorders by functional polymorphism within the ACE gene: the D allele is associated with higher ACE levels and increased neuropeptide degradation, with the result that patients with major depression who carry the D allele have lower depression scores and shorter hospitalization. ACE polymorphism genotypinq might thus identify those patients with major depression likely to benefit from NK1 receptor antagonist therapy.

The expanding field of psychoneuroimmunology has markedly increased knowledge about the interference of the central nervous system and the immune system. Immunological abnormalities in psychiatric patients have been repeatedly described in the last century. Modern concepts of immunology and the growing knowledge of psychoneuroimmunology may help in understanding the distinct immunological mechanisms in psychiatric disorders. One of these concepts regarding the adaptive immune system is the discrimination between Th1-like cell-mediated and Th2-like antibody-related immune responses. This article systematically describes alterations of Th1- or Th2-specific parameters in the major psychiatric disorders schizophrenia, major depression, and Alzheimer's disease. There are several hints of associations of these two distinct arms of immune response with subgroups of schizophrenia and major depression. The immunological research in Alzheimer's disease has already led to a preclinical model of immunotherapy. Categorization of immune parameters may also help to identify a possible immune-related pathophysiology in psychotic and affective disorders, resulting in specific treatment strategies.

The available data on the role of 5-HT in a variety of behaviors support the hypothesis that a dysfunction in brain serotoninergic system activity contributes to vulnerability to major depression. The diversity in the electrophysiological actions of 5-HT in the central nervous system can now be categorized according to receptor subtypes and their respective effector mechanisms. In particular, the implication of central postsynaptic 5-HT2A receptor in affective disorders has been supported by findings consistent with the hypothesis of 5-HT2A receptor up-regulation in depression. For these reasons, the 5-HT2A receptor (HTR2A) gene can be considered as a candidate gene in bipolar affective disorder (BPAD). We tested the possible genetic contribution of the polymorphic DNA variation T102C in exon 1 of HTR2A (chromosome 13q14-21) gene in a large European multicentric case-control sample. Allele and genotype frequencies, as well as homo-heterozygote distributions were compared between the two groups of 309 bipolar affective disorder patients and 309 matched controls. No significant differences were observed in the allelic and genotypic (also for homo-heterozygote) distribution between BPAD and controls. These results indicate that, in our sample, the 5-HT2A receptor polymorphism studied is unlikely to play a major role in the genetic susceptibility to BPAD. Am. J. Med. Genet. (Neuropsychiatr. Genet.) 96:136-140, 2000.

Immune alterations in schizophrenia have been described for decades. However, modern immunological methods and new insights into the highly developed and functionally differentiated immune system allows an integrative view of both, the older and also recent findings of immunological abnormalities in schizophrenia. Both, the unspecific and the specific arm of the immune system seem to be involved in the dysfunction of the immune system in schizophrenia. The unspecific "innate" immune system shows signs of an overactivation in unmedicated schizophrenic patients, as increased monocytes and gamma delta-cells point to. Increased levels of Interleukin-6 (IL-6) and the activation of the IL-6 system in schizophrenia might also be the result of the activation of monocytes/macrophages. On the contrary, several parameters of the specific cellular immune system are blunted, e.g. the decreased T-helper-1 (TH-1) related immune parameters in schizophrenic patients both, in vitro and in vivo. It seems that a TH-1-TH-2 imbalance with a shift to the TH-2 system is associated with schizophrenia. During antipsychotic therapy with neuroleptics, the specific TH-1 related immune answer becomes activated, but also the B-cell system and the antibody production increases.

Objective. To analyze the genotypes of the promoter region of the serotonin transporter gene (5-HTT) in patients with fibromyalgia (FM). Methods. Genomic DNA from 62 patients meeting the American College of Rheumatology 1990 criteria for FM and 110 healthy controls was analyzed by polymerase chain reaction. Additionally, the psychopathologic state of 52 of the FM patients was evaluated using the Beck Depression Inventory (BDI) and the Symptom Checklist-90-Revised (SCL-90-R). Results. The 5-HTTLPR genotypes in FM patients versus controls were distributed as follows: L/L 27% versus 34%, L/S 42% versus 50%, and S/S 31% versus 16%. FM patients with the S/S genotype had higher mean scores on the BDI and the SCL-90-R compared with those in the L/L and L/S groups. Conclusion. A higher frequency of the S/S genotype of 5-HTT was found in FM patients compared with healthy controls. The S/S subgroup exhibited higher mean levels of depression and psychological distress. These results support the notion of altered serotonin metabolism in at least a subgroup of patients with FM. Fibromyalgia (FM) is a syndrome of unknown etiology characterized by chronic widespread pain, increased tenderness on palpation, and additional symptoms such as disturbed sleep, stiffness, fatigue, and psychological distress (1). The pathophysiologic mechanisms underlying FM have been hypothetically linked to disturbances in serotonin (5-HT) metabolism and transmission (2). This hypothesis is based on several recent findings. Studies have shown that levels of tryptophan (the precursor of serotonin) and other amino acids are decreased in sera of FM patients (3), that FM patients have an abnormal serum tryptophan transport ratio (4), and that 5-HT serum levels in FM patients are lower compared with controls (2,5). Similar abnormalities regarding 5-HT metabolism have been found in the cerebrospinal fluid of FM patients (6,7).

Patients with schizophrenia rarely develop rheumatoid arthritis, an autoimmune disease that exhibits genetic association with the HLA DRB1*04 gene. We previously investigated the hypothesis that schizophrenia is negatively associated with DRB1*04, and found that only half the expected number of schizophrenic patients had this gene when compared with controls. We now report the results of DRB1*04 genotyping in pedigrees multiply affected with schizophrenia. Polymerase chain reaction amplification and sequence-specific oligonucleotide probes were used to determine the DRB1 genotypes of the 187 members of 23 pedigrees multiply affected with RDC schizophrenia. DQA1, DQB1 and DPB1 genotypes were similarly determined. We analysed data using the extended transmission/disequilibrium test and found a trend for the preferential non-transmission of DRB1*04 alleles from heterozygous parents to their schizophrenic offspring (16 of 23 alleles not transmitted, chi 2 = 3.5, p = 0.06). We found no evidence for a gene of major effect using GENEHUNTER for parametric and non-parametric linkage analysis. The results from this small sample need to be interpreted with caution, but they are in keeping with previous reports and suggest that HLA DRB1*04 alleles may be associated with a reduced risk of schizophrenia.

Despite strong evidence provided by genetic epidemiology of genetic involvement in the aetiology of bipolar and unipolar affective disorders, the exact nature of the predisposing gene(s) is still being investigated through linkage and association studies. The interaction of susceptibility genes and environmental factors in these diseases is also of fundamental importance and requires proper investigation. Interesting theories have recently been proposed examining the possible role of various chromosomal regions, candidate genes and mutations in affective disorders. Reliable multicentre-based methodology is currently being employed to examine these theories, with attention given to statistical analysis and the statistical power of the sample. The present article describes the European Collaborative Project on Affective Disorders (ECPAD) 'Interactions between genetic and psychosocial vulnerability factors', involving 15 European centres. A description is given of the association and family samples collected for the project and also the methodology used to analyse interactions in the gene-psychosocial environment. This material provides a powerful tool in the search for susceptibility genes in affective disorders and takes into account non-genetic aetiological factors.

The proteins MUC18 and Mader have been identified as markers of tumor progression in melanoma cells. MUC18, also known as MCAM (melanoma cell adhesion molecule) and as CD146 (endothelial antigen), is a cell adhesion molecule belonging to the immunoglobulin superfamily. Mader is a transcriptional regulator shown to negatively regulate EGR-1. As it is known that neoplastic cells of neuroectodermal origin frequently express neuron-specific molecules, we studied whether these melanoma-associated antigens are found in normal CNS tissue. We investigated the expression of MUC18/MCAM and Mader in adult human post mortem CNS tissue by immunohistochemistry, immunoblot and two-dimensional gel electrophoresis. Our results show that Mader is preferentially expressed on neurons and glial cells and that the adhesion protein MUC18/MCAM is mainly expressed on vasculature within the CNS. These observations may have important implications for further studies investigating their possible roles in cell adhesion and proliferation control within the CNS.

The implication of cell adhesion molecules (CAMs) in the mediation of the immune response to inflammatory stimuli has been shown in different neurological syndromes. The neural cell adhesion molecule (NCAM) and the myelin associated glycoprotein (MAG) are functionally important CNS-cell adhesion molecules (CAMs) and members of the immunoglobulin gene superfamily (IgSF). Both CAMs are expressed from the time of neuronal induction and myelin formation and are likely to contribute to the generally adhesive properties of neurons and oligodendrocytes. The present study describes, by means of SDS-PAGE and immunoblotting, a novel CNS antigen which is a glycoprotein detected in post mortem frontal lobe tissue of ten subjects at an M(r) 65 and 113 kD which showed the greatest sequence homology to neuronal IgSF members like NCAM. This expected membrane CAM, with probable functions in CNS cell-cell interactions, had been detected first in primary human melanoma cells, with increasing expression as tumors progress and is expected to be a developmentally regulated CAM in neuroectodermal tissues.

There is a long standing controversy if dopamine receptors are present on human lymphocytes. In recent years the expression of dopamine D3 and D5 receptors was demonstrated with molecular biological methods. Using reverse transcription and polymerase chain reaction (RT-PCR) we were able to demonstrate the expression of the dopamine D4 receptor (DRD4) mRNA in human circulating lymphocytes. Direct sequencing of the RT-PCR product assured that it corresponds to the human DRD4 sequence. However, because of the unusual high G/C content of the DRD4, several precautions have to be applied for reliable results.

Alterations in protein composition are often present in diseases of the central nervous system (CNS). Inflammatory processes causing these alterations have been suggested by many authors to underlie the cerebral disturbance in some cases of schizophrenia. In a previous study, two disease-associated additional polypeptides P1 and P2 could be detected in the cerebrospinal fluid (CSF) of 60 out of 123 (49%) schizophrenic patients. These polypeptides were identified as cleavage products of the beta-chain of fibrin(ogen), an acute-phase protein which is increased in inflammatory processes. Because investigations of brain tissue might better reflect the disease process than cerebrospinal fluid, we examined 6 post mortem brains (3 schizophrenics, 3 normal controls) for the presence of fibrin(ogen) and its cleavage products by two dimensional gel electrophoresis followed by immunoblotting. We detected fibrin(ogen) and its degradation products P1 and P2 in all schizophrenic brain tissue samples, but not in that from controls. These results are consistent with previous CSF observations and suggest that a CNS inflammatory process may be occurring in a subgroup of schizophrenic patients.

Several groups have reported weak evidence for linkage between schizophrenia and genetic markers located on chromosome 22q using the lod score method of analysis. However these findings involved different genetic markers and methods of analysis, and so were not directly comparable. To resolve this issue we have performed a combined analysis of genotypic data from the marker D22S278 in multiply affected schizophrenic families derived from 11 independent research groups worldwide. This marker was chosen because it showed maximum evidence for linkage in three independent datasets (Vallada et al., Am J Med Genet 60:139-146, 1995; Polymeropoulos et al., Neuropsychiatr Genet 54:93-99, 1994; Lasseter et al., Am J Med Genet, 60:172-173, 1995. Using the affected sib-pair method as implemented by the program ESPA, the combined dataset showed 252 alleles shared compared with 188 alleles not share (chi-square 9.31, 1df, P = 0.001) where parental genotype data was completely known. When sib-pairs for whom parental data was assigned according to probability were included the number of alleles shared was 514.1 compared with 437.8 not shared (chi-square 6.12, 1df, P = 0.006). Similar results were obtained when a likelihood ratio method for sib-pair analysis was used. These results indicate that may be a susceptibility locus for schizophrenia at 22q12.

SummaryIn acquired peripheral demyelinating disease only few publications point out the possibility of simultaneous involvement of the CNS. We describe two patients with chronic polyneuropathy and monoclonal gammopathy of undetermined significance (MGUS) developing a progressive dementia syndrome with extensive cerebral white matter alterations.

Tryptophan hydroxylase (TPH) as rate limiting enzyme in the biosynthesis of serotonin plays a major role as candidate gene in several psychiatric disorders. Recently a second TPH isoform (TPH2) was identified in mice, which was exclusively expressed in the brain. We investigated whether the mRNA of the human homologue of this new TPH2 isoform is expressed in the human brain but not in peripheral tissues. The study was performed with postmortem specimen obtained from two subjects who died on cardiovascular failure. TPH2 mRNA levels were determined by quantitative real time RT-PCR. TPH2 mRNA was exclusively present in the human brains but not in the investigated peripheral tissues. Our finding may open up new research strategies for the analysis of the repeatedly observed disturbances in the serotonergic system in patients suffering from several psychiatric disorders.

Replication was attempted of a recent report on linkage between bipolar affective disorder and pericentrometric loci on chromosome 18. Linkage to these markers was excluded in a sample of five extended multiplex families using lod-score and affected-pedigree-member methods. In one family, however, the lod score exceeded 1.0. Although the proposed susceptibility genes are unlikely to have a major impact on the occurrence of bipolar disorder, they might modify the genetic risk in a minority of familial cases.

Alterations of the cerebrospinal fluid (CSF) protein contents and the blood brain barrier (BBB) in schizophrenia have been observed by several authors but no relationship to clinical characteristics like psychopathology, the course or the duration of the disease could be described until now. We have studied 27 schizophrenic patients upon each of whom a lumbar punction had been carried out for clinical reasons. The average values of the patients were within the normal range. Nine patients (33%) showed the total protein content to be >45 mg% and 6 (22%) >50 mg%. In the latter 6 patients an impaired BBB (raised albumin CSF/serum quotient) and in 4 patients (15%) a raised CSF immunoglobulin (IgG) were observed. No relation to the patient's age and the duration of the disease was found but correlations with the Scale for the Assessment of Negative Symptoms (SANS) showed significant results in the subscores “affective flattening/affective blunting”, “alogia/paralogia” as well as in the total score with respect to the CSF contents of albumin and IgG (p=0.009−0.02). These correlations suggest that the CSF albumin and the CSF IgG are related to the negative symptomatology in schizophrenia and that patients with these CSF alterations may have a higher risk of developing negative symptoms.

The human γδ T cell receptor (TCR) is normally expressed on lymphoid tissue. Since expression of different molecules of the T cell system has been described for human brain cells, we examined the expr

The human gamma delta T cell receptor is normally expressed on lymphoid tissue. Because expression of different molecules of the T-cell system has been described on human brain cells, we examined the expression of T-cell receptor gamma delta antigens with a panel of various anti-gamma/delta TCR mAbs using immunohistochemistry on different regions of frozen human postmortem tissue of five different brains. We found expression of gamma/delta TCR antigens on brain tissue in different regions of the brain, probably on neurons. Using mAbs against the 70-kd human heat-shock-protein (hsp 70), immunohistochemistry showed staining of microglia. A polymerase chain reaction analysis using a highly sensitive primer sequence against the constant region delta sequence supports the notion that the gamma/delta TCR is expressed in human brain; however, the sequence cannot be assigned to a specific tissue with this method. Both heat shock proteins and the gamma/delta TCR seem to be involved in autoimmune processes, and their expression on colocalizing structures in human CNS may play a role in triggering neuropsychiatric autoimmune disorders.

The antipsychotic effects of dopamine D2 receptor antagonists (neuroleptics) and the psychotomimetic effects of dopamine agonists suggest that a defect of the D2 receptor gene might be a factor in the etiology of schizophrenia. Fifteen families that contained several members suffering from schizophrenia were tested for linkage between the D2 receptor gene and schizophrenia. In addition, four flanking markers were tested. The mode of inheritance was assumed to be dominant. Five different models of the affection status, which ranged from a narrow to a broad definition of the affection status, were studied. Linkage analysis was carried out with dominant, recessive, and intermediate modes of transmission. Two-point and multipoint analyses between schizophrenia and the D2 receptor gene resulted in log-likelihood differences < -2 for all five models, and linkage between this candidate gene and schizophrenia was excluded. A mutation in the D2 receptor gene itself is therefore extremely unlikely to be related to a higher susceptibility to schizophrenia, at least in the present group of families.

Noradrenergic mechanisms have been involved in the pathogenesis of Gilles de la Tourette Syndrome (GTS). Since the central alpha 2 adrenergic agonist clonidine is widely used as a therapeutic agent in GTS, the present study aimed at assessing whether GH release after clonidine, representing central alpha 2-adrenergic receptor sensitivity, was altered in GTS. After administration of 2 micrograms/kg body weight clonidine, the GH response was examined in nine drug-free, alcohol-abstinent GTS patients (eight men, one woman) and in nine age- and sex-matched abstinent healthy controls. A blunted response of GH release (5 ng/ml) was observed in seven patients and the area under the curve (AUC) of the GH-release was significantly reduced (p.01) compared to controls. This finding indicates an involvement of the noradrenergic system in GTS.

Substance P (for “powder”), identified as a gut tachykinin in 1931 and involved in the control of multiple other autonomic functions, notably pain transmission, is the focus of intense fundamental and clinical psychiatric research as a central neurotransmitter, neuromodulator, and immunomodulator, along with sister neurokinins A and B (NKA and NKB), discovered in 1984. Substance P is widely distributed throughout the central nervous system, where if is often colocalized with serotonin, norepinephrine, and dopamine. Many neurokinin (NK) receptor antagonists and agonists have been synthesized and some clinically tested. A double-blind study of MK869, a selective NK1 receptor antagonist that blocks the action of substance P, showed significant activity versus placebo and fewer sexual side effects than paroxetine in outpatients with major depression and moderate anxiety. Substance P, which is degraded by the angiotensin-converting enzyme (ACE), may mediate modulation of therapeutic outcome in affective disorders by functional polymorphism within the ACE gene: the D allele is associated with higher ACE levels and increased neuropeptide degradation, with the result that patients with major depression who carry the D allele have lower depression scores and shorter hospitalization. ACE polymorphism genotypinq might thus identify those patients with major depression likely to benefit from NK1 receptor antagonist therapy.

Treatment-resistance in schizophrenia remains a public health problem: about 20% to 30% of patients do not respond to antipsychotic therapy. Clozapine has been shown to be effective in about one-third of patients, but the medical risks and weekly blood tests limit its broad application. While the heterogeneity of the disease and the duration of untreated psychosis are important, pharmacogenomic aspects must also be considered. Pharmacogenomic investigations offer the opportunity to individualize antipsychotic therapy according to the growing knowledge of the function and effect of the genetic polymorphisms that affect the pharmacokinetics and pharmacodynamics of antipsychotics. On the pharmacokinetic level, polymorphic phase I and II drug-metabolizing enzymes and transport proteins affect drug concentration at the target structure. The cytochrome P450 enzymes, N-acetyltransferase, and multidrug resistance protein (MDR1) particularly influence this parameter. Genetic alterations affecting drug pharmacodynamic properties have an impact on therapeutic outcome that is generally independent of the applied dosage regimen. A combined analysis of genetic polymorphisms in the dopaminergic and serotonergic receptors, neurotransmitter transporters, and other target structures involved in psychiatric disorders is already a powerful predictor of therapeutic outcome. An understanding of other factors influencing gene expression and protein production will facilitate individualized therapy in the future.

Muller, Norbert, Elisabeth Hofschuster, Manfred Ackenheil, Wolfgang Mempel and Reinhold Eckstein: Investigations of the Cellular Immunity during Depression and the Free Interval. Evidence for an Immune Activation in Affective Psychosis. Prog. Neuro-PsychopharmacoL & Biol. Psychiat. 1993, 17(5); 713–730. 1. 1. Results of investigations of the immune function in affective disorders are conflicting. Some authors described an immune suppression, others an immune activation in major depression. The authors performed a study of cellular immunity in the MDD subtype endogenous depression. 23 patients suffering from endogenous depression were investigated during the depressive state, the results were compared with a group of 14 patients during the free interval and 51 healthy controls. 2. 2. The lymphocyte proliferation after incubation with diphteria- and tetanus toxoid, mainly stimulating T-cells, was reduced but after incubation with an antigen-cocktail, stimulating both, T- and B-cells, was increased in patients during depression and during the free interval compared to controls. 3. 3. The CD3+ - and CD4+ -cells were significantly enhanced in both groups of patients while the CD8+-cells showed no differences to the controls. The ratio CD4+/CD8+ was increased in patients, too, as described in some autoimmune disorders. 4. 4. The suppressor cell activity was significantly reduced in the PWM-assay and in the PHA-assay. The mixed lymphocyte culture showed a tendency to reduced suppressor cell activity as well 5. 5. The results point to an immune activitation and to a disturbed control of the proliferative activity in affective psychosis. A T-cell related defect, not compensated by an increased number of CD3+ - and CD4+ -cells is discussed. 6. 6. From our point of view, the conflicting results of psychoneuroimmunological investigations m depressive disorders may be related to etiologically different subgroups of depression. The diagnostic category of MDD is possibly one of the traps in psychoneuroimmunology.

Until recently, attention has been focused on the pathogenetic aspects of immunological findings in schizophrenic patients. There has been no mention of the relationship between such findings and schizophrenic symptoms. To study the probable relationship between T-cells and T-cell subgroups in the course and prognosis of schizophrenia, immunological and psychopathological parameters were correlated in 55 patients suffering from schizophrenia (ICD-9: 295.0-295.6) or schizoaffective psychosis (ICD-9: 257.7) before neuroleptic treatment. The correlations were performed for a second time in 24 of these patients after clinical improvement at a reinvestigation. Positive correlations of the Brief Psychiatric Rating Scale and the Scale for Assessment of Negative Symptoms with the numbers of CD3+ and CD4+ T-cells (total T- and T-helper cells), which were enhanced compared with controls, were found at the reinvestigation after clinical improvement, whereas no significant correlation could be detected at the pretreatment investigation. These results show that the cellular immune parameters are related to the course of the psychopathological symptoms in schizophrenia and, possibly, are a marker of the therapeutic outcome or neuroleptic treatment.

The clinical action of Zotepine was examined in an open and in a randomised double-blind controlled study in in-patients displaying a productive or minus pattern of symptoms within the framework of a schizophrenic disease or schizoaffective psychosis. The present paper discusses only the results achieved in treating schizophrenic minus patterns of signs and symptoms. In Study I 20 schizophrenic patients were treated with two different Zotepine dosages. Group 2 (n = 12) showed at an average daily dose of 168 +/- 15 mg (150-190 mg) a significant improvement (p less than 0.05) of the anergy subscore in the BPRS scale as well as a significant improvement of the subscores affective flattening, anhedonia/asociality and attentional imparvement in the SANS scale, compared with Group 1 (n = 8) with an average daily dose of 270 +/- 37 mg (240-340 mg). This improvement developed already during the first two weeks of the treatment. In Study II the antipsychotic action of Zotepine compared to that of perazine was studied under double-blind conditions. The average daily dose in the Zotepine group (n = 20) was around 241 +/- 70 mg (106-396 mg), in the perazin group (n = 19) at 348 +/- 09 mg (214-575 mg). With regard to the BPRS subscore anergy and all the subscores of the SANS scale, there was a distinct improvement without significant group differences. Both substances were comparably well tolerated.