Imbalanced PTEN and PI3K Signaling Impairs Class Switch Recombination

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 ...

Critical Roles of Pten in B Cell Homeostasis and Immunoglobulin Class Switch Recombination

Pten is a tumor suppressor gene mutated in human cancers. We used the Cre-loxP system to generate a B cell-specific mutation of Pten in mice (bPten(flox/flox)mice). bPten(flox/flox) mice showed elevated numbers of B1a cells and increased serum autoantibodies. Among B2 cells in bPten(flox/flox) spleens, numbers of marginal zone B (MZB) cells were significantly increased while those of follicular...

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...

Rnf8 deficiency impairs class switch recombination, spermatogenesis, and genomic integrity and predisposes for cancer

Signaling and repair of DNA double-strand breaks (DSBs) are critical for preventing immunodeficiency and cancer. These DNA breaks result from exogenous and endogenous DNA insults but are also programmed to occur during physiological processes such as meiosis and immunoglobulin heavy chain (IgH) class switch recombination (CSR). Recent studies reported that the E3 ligase RNF8 plays important rol...