Naive CD4+ T cells and recent thymic emigrants in common variable immunodeficiency.

BACKGROUND: Common variable immunodeficiency (CVID) comprises a heterogeneous group of disorders classified as predominantly antibody deficiencies. The aim of this study was to analyze levels of naïve CD4+ T cells and recent thymic emigrant (RTE) cells in CVID patients and healthy controls. METHODS: Twenty patients with CVID and 20 age- and sex-matched healthy controls were studied. CD4+ T cells were negatively isolated from peripheral blood mononuclear cells by magnetic beads, and cell surface markers (CD45RA, CD62L and CD31) were assessed by flow cytometry. The normal range of naïve CD4+ T cells detected in the control group (33%-63%) was used to classify the CVID patients into 2 groups (< or = 33% and >33% naïve CD4+ T cells). RESULTS: Naïve CD4+ T cells (CD45RA+ CD62L+) and RTE cells (CD45RA+CD62L+CD31+) were significantly lower in male CVID patients compared to both female patients and healthy male controls. There were also more male patients in the group with naive CD4+ T-cell levels of 33% or less. Autoimmunity was only observed in this group. CONCLUSIONS: Lower numbers of naïve CD4+ T cells and RTE cells in male CVID patients might be due to lower thymic output in these patients. The classification of patients based on naïve CD4+ T cell levels seems to be consistent with clinical features.

Molecular diagnosis of trichomoniasis in negative samples examined by direct smear and culture.

BACKGROUND: Trichomoniasis is an extremely common sexually transmitted infection (STI) worldwide and is associated with important public health problems, including amplification of HIV transmission. This disease is in forms of symptomatic and asymptomatic in women and may depend on host as well as parasite variables. Most of the studies reported from females are based on examination of vaginal secretions and urine samples by direct smear and culture in modified Diamond's media. The aim of this study was checking the samples, which were negative by direct smear and culture, with PCR technique. METHODS: The urine samples and vaginal discharge of patients attending Gynecology Clinics of Mazandaran Province, Iran with different symptoms rechecked for Trichomonas vaginalis by PCR technique using primers targeting a conserved region of the beta-tubulin genes of the parasite. Data were analyzed by Epi Info software program RESULTS: Out of 161 negative samples by direct smear and culture, seven samples (4.3%) were positive by PCR technique. CONCLUSION: Diagnosis of trichomoniasis by PCR is a sensitive and specific method that could play important role to help the physicians for properly treatment and control of infection.

Efficacy and long-term immunogenicity of hepatitis B vaccine in haemodialysis patients.

BACKGROUND: Hepatitis B vaccine is effective in protection against hepatitis B virus (HBV) infection in haemodialysis (HD) patients, but the antibody response is variable in this population and the persistence of immunity in them remains largely unknown. In this study we aimed to evaluate the efficacy and long-term immunogenicity of hepatitis B vaccine in HD patients. METHODS: In this study, we initially offered HBV vaccination as double dose, four vaccine series schedule (40 microg injections intramuscularly in the deltoid muscle at 0, 1, 2 and 6 months) to 54 HD patients who were negative for hepatitis B core antibody and did not receive any dose of HBV vaccine previously. Serum levels of hepatitis B surface antibody (anti-HBs) tested 1-2 months after completion of vaccination. Then we follow the patients up to 1 year after primary vaccination to evaluate the persistence of immunity (as indicated by serum levels of anti-HBs higher than or equal to 10 IU/l). RESULTS: After primary vaccination, 87% of patients developed anti-HBs levels above 10 IU/l. 27.8% and 59.2% of them were weak responders and high responders respectively. 13% of patients were non-responders. After 1-year follow-up, 18.18% of responders had lost their anti-HBs (transient responders). All of them were initially in weak responders group and had lower anti-HBs levels. CONCLUSION: We found an average percentage of seroconversion after primary HBV vaccination in HD patients. Our study also supported this fact that an antibody titre above 100 IU/l following primary vaccination is necessary to maintain that level of antibody 1 year later.

Frequency analysis of HBsAg-specific B lymphocytes in high-responder individuals to recombinant hepatitis B vaccine: comparison of LDA and ELISPOT assays.

The determination of the frequency of antigen-specific lymphocytes may provide invaluable information for the evaluation of the immune response to different antigens and pathogens. Different methods are employed to determine the frequency of specific B lymphocytes in peripheral blood. In this study, the frequency of hepatitis B surface antigen (HBsAg)-specific B lymphocytes was determined by a limiting dilution assay (LDA) and an enzyme-linked immunospot assay (ELISPOT) in seven healthy adult high responders to recombinant HBsAg. Peripheral blood mononuclear cells isolated at different time intervals (1, 2, 4, 8 and 16 weeks) following administration of a booster dose were either transformed with Epstein-Barr virus (LDA) or stimulated with Pokeweed mitogen (ELISPOT). In an LDA, anti-HBs positive wells were screened by a sandwich ELISA and the frequency of specific B lymphocytes was estimated based on the Poisson statistical analysis. In an ELISPOT, coloured spots representing specific B lymphocytes were finally enumerated by stereomicroscope. Our results showed a significant increase in the number of specific B lymphocytes in the first week by an ELISPOT compared with an LDA (1:190 versus 1:13,462) (P < 0.001). No significant differences were observed at other time intervals. A significant correlation was observed between the serum titer of anti-HBs antibody and frequency of HBsAg-specific B cells obtained by LDA and ELISPOT methods at different time intervals. The highest correlation was found at fourth week in LDA (r = 0.83, P < 0.01) and ELISPOT (r = 0.85, P < 0.01) assays. Furthermore, a significant correlation was observed between an LDA and ELISPOT at different time intervals (highest correlation in second week, r = 0.88, P < 0.008). These findings suggest that in addition to technical advantages, such as speed and simplicity, an ELISPOT is a more sensitive assay, compared with an LDA.

Molecular differentiation of ischemic and valvular heart disease by liquid chromatography/fourier transform ion cyclotron resonance mass spectrometry.

Proteomic patterns of myocardial tissue in different etiologies of heart failure were investigated using a direct analytical approach with High Performance Liquid Chromatography (HPLC)/Fourier Transform Ion Cyclotron Resonance Mass Spectrometry (FT-ICR MS). Right atrial appendages from 20 patients, 10 with hemodynamically significant isolated aortic valve disease and 10 with symptomatic coronary artery disease were collected during elective cardiac surgery. After preparation of tissue samples and tryptic digestion of proteins, the peptide mixture was HPLC-separated and on-line analyzed by electrospray FT-ICR MS. Data obtained from HPLC / FT-ICR MS runs were compared for classification. To extract the classification features, the selection of best individual features was applied and the "nearest mean classifier" was used for the classification of test samples and the sample projection onto classification patterns. The pattern distribution characteristics of aortic and coronary diseases were clearly different. No interference between samples of both disease categories was registered, even if the distribution of unsupervised classified test samples were closer. Samples representing aortic valve disease showed a closer accumulation pattern of spots compared to the samples representing coronary disease, which indicated a more specific protein classification. Through selective identification of specific peptides and protein patterns with FTMS, valvular and coronary heart disease is for the first time clearly distinguished at molecular level. The described methodology could also be feasible in search for specific biomarkers in plasma or serum for diagnostic purposes.

Interferon-beta affects the tryptophan metabolism in multiple sclerosis patients.

Tryptophan and its metabolites are of great interest in understanding the pathogenesis of multiple sclerosis (MS). The total levels of tryptophan and its metabolites, kynurenine and kynurenic acid were determined in plasma by capillary liquid chromatography electrospray ionisation tandem mass spectrometry. This is the first report of the plasma levels of these analytes in healthy controls and relapsing-remitting MS patients receiving long-term and acute interferon-beta (IFN-beta) treatment. Twenty-four hours post-administration increased kynurenine levels (first IFN MS versus healthy, P = 0.042) and kynurenine/tryptophan ratio (K/T; first IFN MS versus healthy, P =0.027; first IFN MS versus long-term IFN MS, P = 0.036) were found. The long-term IFN MS group had higher K/T ratios at 4 and 12 h post-administration (P = 0.015 and 0.009, respectively). The increase of K/T ratio in the first IFN MS group indicate an induction of the enzyme indolamine-2,3-dioxygenase (IDO), as reported earlier in experimental allergic encephalomyelitis. As IDO is participating in both inflammatory and neurodegenerative processes, further knowledge of its involvement in the pathogenesis of MS is of great importance.

Micro-capillary liquid chromatography Fourier transform ion cyclotron resonance mass spectrometry--a powerful tool for peptide and protein identification.

In order to be able to study complex biological samples, a micro-capillary liquid chromatography system was coupled to a 9.4 T Fourier transform ion cyclotron resonance mass spectrometer. The setup was tested on a tryptic digest of bovine serum albumin, which resulted in high sequence coverage (> 92%) of the protein.

[Toxoplasmosis in Iran. Results of a seroepidemiological study]. / Toxoplasmose en Iran. Résultats d'une étude séroépidémiologique.

A toxoplasmosis seroepidemiological survey was effected with 13,018 sera collected by stratified cluster random sampling method from 12 provinces in Iran. The samples were studied by indirect immunofluorescent assay (IFA) for the presence of Toxoplasma. In this study, 52.6% of the subjects were male and the remaining 47.4% were female. Anti-Toxoplasma antibody was detected in a total of 51.8% of the samples with no significant difference between male and female affected subjects. The distribution of the infected samples was also investigated in various age groups, the level of infection to Toxoplasma increasing from childhood, culminating to 30 years of age and gradually declining from there after. Between the various age groups, the 10-19 years old demonstrated a 50% increase in relative risk to the infection with high antibody titer. Within the provinces under study, the highest relative frequency of Toxoplasma antibody titer was indicated in Mazandaran province (20.5%), while the lowest frequency was detected in Hormozgan (2.9%). In general, there was a decrease in the number of infected samples from humid areas in north to dry provinces in south of Iran. In the clinical symptoms study, no significant difference between male and female patients was demonstrated. According to the type of clinical manifestation, lymphadenopathy and central nervous system symptoms (encephalitis) were respectively the most and the least frequent manifestations.