Class switch recombination in selective IgA-deficient subjects

IgA class switch in I alpha exon-deficient mice. Role of germline transcription in class switch recombination.

Studies have implicated defective Ig class switch in the pathogenesis of IgA deficiency. To understand better the molecular events that regulate IgA class switch, a 1.4-kb region of the IgA locus containing the I alpha exon was replaced with a human hypoxanthine phosphoribosyltransferase minigene by gene targeting in murine embryonic stem cells. The I alpha exon-deficient mice derived from thes...

Immunoglobulin Class Switch Recombination Is Impaired in Atm-deficient Mice

Immunoglobulin class switch recombination (Ig CSR) involves DNA double strand breaks (DSBs) at recombining switch regions and repair of these breaks by nonhomologous end-joining. Because the protein kinase ataxia telengiectasia (AT) mutated (ATM) plays a critical role in DSB repair and AT patients show abnormalities of Ig isotype expression, we assessed the role of ATM in CSR by examining ATM-d...

onychomadesis in a patient with immunoglobulin class switch recombination deficiency

immunoglobulin class switch recombination deficiencies (ig csr deficiencies) or hyper igm syndromes (higm) are a group of primary immunodeficiency diseases, characterized by defective cd40 signaling of b cells resulting into a csr and a somatic hypermutation. the affected patients are characterized with reduced serum levels of igg and iga, and normal or elevated level of igm, which lead to incr...

Interallelic Class Switch Recombination

Immunoglobulin class-switch recombination deficiencies

Immunoglobulin class-switch recombination deficiencies (Ig-CSR-Ds) are rare primary immunodeficiencies characterized by defective switched isotype (IgG/IgA/IgE) production. Depending on the molecular defect in question, the Ig-CSR-D may be combined with an impairment in somatic hypermutation (SHM). Some of the mechanisms underlying Ig-CSR and SHM have been described by studying natural mutants ...