Somatic hypermutation normally occurs as a consequence of the expression of activation-induced cytidine deaminase (AID) by Ag-activated, mature B cells during T cell-dependent germinal center responses. Nonetheless, despite their inability to express CD154 and initiate GC responses, patients with type 1 hyper-IgM syndrome (HIGM1) support populations of IgM(+)IgD(+)CD27(+) B cells that express m...

To study the role of the CD40-CD40 ligand interaction in the development of memory B cells and its level of action during primary antibody responses in vivo, mice were injected with a soluble CD40 fusion protein (sCD40-gamma 1), so as to block the interaction. The effects of the treatment on the primary antibody response were reminiscent of hyper-immunoglobulin M (IgM) syndrome (HIMG1): antigen...

The present study analyzed peripheral blood B cell populations separated by IgD and CD27 expression in six males with X-linked hyper-IgM syndrome (XHIM). Costimulation of mononuclear cells from most of the patients induced no to low levels of class switching from IgM to IgG and IgA with Staphylococcus aureus Cowan strain (SAC) plus IL-2 or anti-CD40 mAb (anti-CD40) plus IL-10. Measurable levels...

Ataxia-telangiectasia (AT) and hyper-immunoglobulin M (HIGM) syndrome are both primary immunodeficiency diseases caused by different genetic defects. While a small proportion of AT patients have increased serum immunoglobulin (Ig) M concentrations during the course of a disease, a high level of IgM at onset is rare. We report the case of an 8-year-old girl who had experienced recurrent respirat...

Background: Hyper IgE syndrome (HIES) is a rare primary immune deficiency, described as Job`s syndrome characterized by increased serum levels of IgE, eczema, recurrent cutaneous and pulmonary infections. In this paper, we presented a case of Hyper IgE syndrome.Case Presentation: A 16-year-old Iranian boy presented with a one year history of skin lesions in knees and elbows was diagnosed of pso...

X-linked hyper-IgM syndrome (XHIM) results from mutations in the gene encoding for CD40 ligand (CD154). Patients with the syndrome suffer from infections with opportunistic pathogens such as Cryptosporidium and Pneumocystis carinii. In this study, we demonstrate that activated T cells from patients with XHIM produce markedly reduced levels of IFN-gamma, fail to induce antigen-presenting cells t...

background: release of vascular endothelial growth factor (vegf) by ovaries in response to hcg administration is one of the main mechanisms of ovarian hyper stimulation syndrome. since dopamine/dopamine receptor2 (dp-r2) pathway activity -mediated by vegf/ vascular endothelial growth factor receptor 2 (vegfr-2) signaling-, is associated with angiogenic events, dopamine agonists were used for th...