Outcome of influenza vaccination in combat-related post-traumatic stress disorder (PTSD) patients.

Post-traumatic stress disorder (PTSD) is an anxiety disorder that can occur after exposure to extreme traumatic experience such as war trauma, and is accompanied by fear, helplessness or horror. Exposure to trauma can result in immune dysregulation and influence susceptibility to infectious disease as well as vaccine efficacy. The aim of the study was to determine the relation of psychological stress and the immune response to influenza vaccination in combat-related PTSD patients (n = 28). Detection of anti-viral antibody titre was performed by inhibition of haemagglutination assay. Ex vivo tetramer staining of CD8(+) T lymphocytes was used to monitor T cells specific for human leucocyte antigen (HLA)-A*0201-restricted influenza A haemagglutinin antigens before and after vaccination. Twenty patients showed a fourfold antibody titre increase to one or both influenza A viral strains, and 18 of them showed the same response for both influenza B viral strains. Ten of 15 healthy controls showed a fourfold rise in antibody titre to both influenza A viral strains and eight of them showed the same response for both influenza B viral strains. HLA-A*0201(+) PTSD patients (n = 10) showed a significant increase of influenza-specific CD8 T cells after vaccination. Although those PTSD patients had a lower number of influenza-specific CD8(+) T cells before vaccination compared to HLA-A*0201(+) healthy controls (n = 6), there was no difference in influenza A antibody titre between PTSD patients and control subjects before vaccination. The generated humoral and cellular immune response in PTSD patients argues against the hypothesis that combat-related PTSD in war veterans might affect protection following influenza vaccination.

Increased Toll-like receptor 4 expression in infants with respiratory syncytial virus bronchiolitis.

The fusion protein of the respiratory syncytial virus (RSV) binds to the pattern recognition receptors, TLR4 and CD14, and initiates innate immunity response to the virus. The aim of the study was to investigate the expression of TLR4 on peripheral blood lymphocytes and monocytes in peripheral blood of infants in both acute and convalescent phase of RSV bronchiolitis (n = 26). In addition, TNF-alpha expression in lipopolysaccharide-stimulated monocytes was also assessed. The results showed TLR4 to be expressed predominantly by monocytes in both sick infants and controls. During the acute phase of infection monocytes up-regulated TLR4 in eight infants, which returned to the levels recorded in controls 4-6 weeks from infection. There was no difference in the percentage of TNF-alpha secreting monocytes. Of the clinical parameters tested, minimal oxygen saturation was found to correlate negatively with this expression in the group of infants with increased TLR4. Additional studies are under way to correlate this finding with the outcome of the immune response to RSV.

Flow cytometric determination of glucocorticoid receptor (GCR) expression in lymphocyte subpopulations: lower quantity of GCR in patients with post-traumatic stress disorder (PTSD).

Assessment of the intracellular glucocorticoid receptor (GCR) level may be useful in monitoring functional disturbances of the hypothalamic-pituitary-adrenocortical axis or effects of prolonged steroid therapy. Cytosolic ligand binding assays have recently been supplemented by flow cytometric determination of receptor expression in individual cells. A method based on multiparametric analysis of whole blood by simultaneous labelling of intracellular GCRs and surface markers of lymphocyte subsets is described. We examined 25 healthy male volunteers and 35 age- and sex-matched post-traumatic stress disorder (PTSD) patients within 8 years from traumatic event. PTSD patients had a lower relative quantity of GCR in all lymphocyte populations tested as compared with healthy volunteers. NK cells of both groups showed higher expression of GCR than other lymphocyte subsets. In PTSD patients, the expression of GCR in B lymphocytes was also higher than in T cell. Although serum cortisol level was lower in PTSD patients, there was no correlation between cortisol level and GCR expression. Multiparameter flow cytometric determination of GCR expression in lymphocyte subpopulations may provide a useful tool for monitoring immunoregulatory action of glucocorticoids.