Expression, purification and characterization of three overlapping immunodominant recombinant fragments from Bordetella pertussis filamentous hemagglutinin

Filamentous hemagglutinin [FHA] is one of the most important immunoprotective antigens of Bordetella pertussis [B. pertussis] and a major component of the acellular pertussis vaccine. In the present study, three overlapping recombinant fragments from the immunodominant region of FHA were produced and their immunogenicity was investigated. Three overlapping coding sequences of FHA antigen were amplified from B. pertussis genomic DNA by PCR. Amplified fragments were expressed in Escherichia coli [E. coli] BL21[DE3] strain and purified through His-tag using Nickel-based chromatography. Purified fragments were characterized by SDS-PAGE and Western blotting techniques. In vitro peripheral blood mononuclear cells [PBMC] proliferation and IFN- gamma production were assessed in a limited number of healthy adults vaccinated with a commercial acellular pertussis vaccine in response to all purified FHA fragments by H3-Thymidine incorporation and ELISA, respectively. Recombinant FHA segments were successfully cloned and produced at high levels in E. coli BL21[DE3]. SDS-PAGE and Western blot analyses confirmed their purity and reactivity. All three recombinant fragments together with a commercial native FHA were able to induce in vitro PBMC proliferation and IFN- gamma production. Our preliminary results suggest that these overlapping recombinant FHA fragments are immunogenic and may prove to be immunoprotective

Foxp3 gene expression in multiple sclerosis patients pre- and post mesenchymal stem cell therapy

Multiple Sclerosis [MS] is an inflammatory demyelinating and neurodegenerative disorder of the central nervous system [CNS], which mainly affects young adults. Activated T lymphocytes promote the neuro-inflammatory cascade of MS by secreting pro-inflammatory cytokines and play a significant role in its pathogenesis. T lymphocytes may trigger the inflammation, which in turn leads to axonal loss and neurodegeneration observed in the course of MS. Currently, there is no cure for MS, however, one of the most promising neuroprotective research tools consists of the use of bone marrow derived mesenchymal stem cells [MSC]. This method promotes immune system regulation and possibly induces neurological repair and re-myelination of the damaged axons. Recent studies have shown that MSC exert an immune regulatory function and induce T regulatory-cell proliferation, therefore, it may serve as a potentially useful treatment for immune-mediated diseases such as MS. In this pilot study a group of MS patients underwent MSC therapy and we assayed the expression of an X-linked transcription factor, FoxP3, as a specific marker of T Regulatory cells in peripheral blood, prior to and after the treatment. Using q RT-PCR for measurement of expression of FoxP3 by peripheral blood mononuclear cells, we found that in all subjects, except for one, the expression of FoxP3 at 6 months after intrathecal injection of MSC was significantly higher than the levels prior to treatment. Such significant enhanced expression of FoxP3 associated with clinical stability. Findings from this pilot study further support the potential of bone marrow derived MSC for treatment of MS patients

Determination of HLA-B27 subtypes in Iranian patients with ankylosing spondylitis

The human leukocyte antigen-B27 is one of the class I molecules of the major histocompatibility complex which is strongly associated with ankylosing spondylitis [AS]. The strength of the disease association with B27 varies markedly among racial and ethnic populations. It is an allele family, which constitutes about 31 subtypes, with a considerable geographic and ethnic difference in distribution. It is important to know whether certain subtypes show any preferential association with AS. Because there is no report regarding HLA-B27 subtypes in Iranian patients with AS, main purpose of the present study was to assess the frequency of subtypes of human leukocyte antigen [HLA]-B27 in patients with ankylosing spondylitis in Iranian population One hundred and nineteen AS patients [82 HLA-B27 positive and 37 HLA-B27 negative] were selected for this study. HLA-B27 positive patients were by polymerase chain reaction amplification with sequence-specific primers [PCR-SSP] for B 27 subtyping. The results of present study revealed that only two subtypes were detected in Iranian patients, including B 2705 [52 patients, 63.4%] and B 2702 [30 patients, 36.6%]. Our results showed a restricted number of HLA-B27 subtypes associated with AS in Iran and an elevated frequency of the B 2705 allele in these patients similar to other Euro-Caucasoid [Aryan] groups in the world