1Brain Behav. Immun. 2009 Jan 23: 134-42
PMID18771722
TitleFlow cytometric analysis of T cell subsets in paired samples of cerebrospinal fluid and peripheral blood from patients with neurological and psychiatric disorders.
AbstractRecent studies suggest inflammatory mechanisms involved in the pathogenesis of major psychiatric disorders (MPD). T cells play a major role during inflammation, but little is known about T cell subpopulations in the cerebrospinal fluid (CSF). We investigated the frequency of cells positive for the surface markers CD4, CD8, CD25, CD45, CD69, and CD127 in 45 paired cerebrospinal fluid (CSF) and peripheral blood (PB) samples by multiparameter flow cytometry from patients with MPD of the schizophrenic and affective spectrum with normal CSF cell counts and compared them with those from patients with non-inflammatory (NIND), chronic inflammatory (CIND) neurological disorders, and meningitis (MEN). In MEN patients, CD4+ cell frequency in PB, but not in CSF, was significantly increased as compared to CIND and NIND. No difference between patient groups was observed for CD8+. CD4+CD45RO+ double positive cells in PB were significantly lower in CIND than in MEN or NIND. The frequency of CD4+CD25+ cells in PB was significantly higher in MEN than in MPD or CIND. For CSF, the percentage of CD4+CD127(dim) cells was significantly lower in MEN than in MPD. CD4+CD127(dim) in PB and CSF showed overlapping characteristic clusters between MPD and CIND and MEN patients. Overall, the hypothesis of low degree inflammation in a subgroup of MPD is supported. The analysis of lymphocyte subsets in PB and CSF constitutes a novel promising tool to understand underlying pathomechanisms in psychiatric and neurological disorders on an individual case level.
SCZ Keywordsschizophrenia, schizophrenic
2Mol. Psychiatry 2010 Apr 15: 364-71
PMID19002140
TitleDifferential effects on T-cell function following exposure to serum from schizophrenia smokers.
AbstractCigarette smoking is more prevalent in subjects with schizophrenia compared to those with other psychiatric disorders or the general population and could therefore affect molecular pathways that impact the pathophysiology of this disorder. As smoking is also known to suppress immune responses, we investigated the effects of 'smoking-conditioned' serum obtained from schizophrenia and control subjects on healthy T cell in vitro. We found that T-cell proliferation was significantly increased following exposure to serum from smoking schizophrenia patients whereas no effect was observed when using serum from smoking control subjects or non-smoking patients and controls. We eliminated the possibility that these effects were due to quantitative differences in cigarette consumption as serum levels of the stable nicotine metabolite cotinine were similar in schizophrenic and control smokers. Molecular characterization showed that serum from patient smokers increased expression of T-cell activation markers CD69(high), CD25(high), co-stimulatory molecules CD26+, CD27+ and CD28+, and decreased T-cell receptor complex components TCRalpha/beta and CD3. Moreover, analysis of supernatants collected after T-cell exposure to serum from smoking patients showed a time-dependent decline in interleukin (IL)-2 levels, suggesting that the proliferation effect is promoted by enhanced IL-2 processing. These results suggest that cigarette smoking has selective effects on serum components that, in turn, lead to altered immune function in schizophrenia patients relative to healthy subjects. Further studies aimed at characterizing these components could result in a better understanding of the onset and aetiology of schizophrenia and potentially lead to novel therapeutic strategies.
SCZ Keywordsschizophrenia, schizophrenic
3Mol. Psychiatry 2010 Apr 15: 364-71
PMID19002140
TitleDifferential effects on T-cell function following exposure to serum from schizophrenia smokers.
AbstractCigarette smoking is more prevalent in subjects with schizophrenia compared to those with other psychiatric disorders or the general population and could therefore affect molecular pathways that impact the pathophysiology of this disorder. As smoking is also known to suppress immune responses, we investigated the effects of 'smoking-conditioned' serum obtained from schizophrenia and control subjects on healthy T cell in vitro. We found that T-cell proliferation was significantly increased following exposure to serum from smoking schizophrenia patients whereas no effect was observed when using serum from smoking control subjects or non-smoking patients and controls. We eliminated the possibility that these effects were due to quantitative differences in cigarette consumption as serum levels of the stable nicotine metabolite cotinine were similar in schizophrenic and control smokers. Molecular characterization showed that serum from patient smokers increased expression of T-cell activation markers CD69(high), CD25(high), co-stimulatory molecules CD26+, CD27+ and CD28+, and decreased T-cell receptor complex components TCRalpha/beta and CD3. Moreover, analysis of supernatants collected after T-cell exposure to serum from smoking patients showed a time-dependent decline in interleukin (IL)-2 levels, suggesting that the proliferation effect is promoted by enhanced IL-2 processing. These results suggest that cigarette smoking has selective effects on serum components that, in turn, lead to altered immune function in schizophrenia patients relative to healthy subjects. Further studies aimed at characterizing these components could result in a better understanding of the onset and aetiology of schizophrenia and potentially lead to novel therapeutic strategies.
SCZ Keywordsschizophrenia, schizophrenic
4Brain Behav. Immun. 2011 May 25: 604-15
PMID21195166
TitleActivation of the maternal immune system induces endocrine changes in the placenta via IL-6.
AbstractActivation of the maternal immune system in rodent models sets in motion a cascade of molecular pathways that ultimately result in autism- and schizophrenia-related behaviors in offspring. The finding that interleukin-6 (IL-6) is a crucial mediator of these effects led us to examine the mechanism by which this cytokine influences fetal development in vivo. Here we focus on the placenta as the site of direct interaction between mother and fetus and as a principal modulator of fetal development. We find that maternal immune activation (MIA) with a viral mimic, synthetic double-stranded RNA (poly(I:C)), increases IL-6 mRNA as well as maternally-derived IL-6 protein in the placenta. Placentas from MIA mothers exhibit increases in CD69+ decidual macrophages, granulocytes and uterine NK cells, indicating elevated early immune activation. Maternally-derived IL-6 mediates activation of the JAK/STAT3 pathway specifically in the spongiotrophoblast layer of the placenta, which results in expression of acute phase genes. Importantly, this parallels an IL-6-dependent disruption of the growth hormone-insulin-like growth factor (GH-IGF) axis that is characterized by decreased GH, IGFI and IGFBP3 levels. In addition, we observe an IL-6-dependent induction in pro-lactin-like protein-K (PLP-K) expression as well as MIA-related alterations in other placental endocrine factors. Together, these IL-6-mediated effects of MIA on the placenta represent an indirect mechanism by which MIA can alter fetal development.
SCZ Keywordsschizophrenia, schizophrenic