Impact of the functional CD5 polymorphism A471V on the response of chronic lymphocytic leukaemia to conventional chemotherapy regimens.

The CD5 lymphocyte receptor -a immunohistochemical marker of chronic lymphocytic leukaemia (CLL) cells- is a negative regulator of activation signals from the antigen-specific B-cell receptor (BCR). Given that signalling components of the BCR are important contributors to the variable clinical behaviour of CLL, the relevance of functional variants of CD5 on CLL prognosis was explored. The results show that germline-encoded variants influence the survival to conventional chemotherapies from CLL patients with unmutated genes.

Analysis of ancestral and functionally relevant CD5 variants in systemic lupus erythematosus patients.

Objective: CD5 plays a crucial role in autoimmunity and is a well-established genetic risk factor of developing RA. Recently, evidence of positive selection has been provided for the CD5 Pro224-Val471 haplotype in East Asian populations. The aim of the present work was to further analyze the functional relevance of non-synonymous CD5 polymorphisms conforming the ancestral and the newly derived haplotypes (Pro224-Ala471 and Pro224-Val471, respectively) as well as to investigate the potential role of CD5 on the development of SLE and/or SLE nephritis.

Identification of functionally relevant phoshorylatable serine clusters in the cytoplasmic region of the human CD6 lymphocyte surface receptor.

CD6 is a transmembrane receptor expressed by all T and a subset of B lymphocytes, where it physically associates with the antigen-specific receptor to modulate activation and differentiation processes through still poorly understood mechanisms. Its cytoplasmic tail lacks intrinsic catalytic activity but presents several consensus motifs for phosphorylation. The present work reports on the identification of two constitutively phosphorylated serine clusters (S480/482/484 and S560/562/565/567/568), which are embedded into Casein Kinase 2 consensus motifs, and are indispensable for proper mitogen-activated protein kinase activation following CD6 ligation.

Evolutionary and functional evidence for positive selection at the human CD5 immune receptor gene.

CD5 is a lymphocyte surface coreceptor of still incompletely understood function. Currently available information indicates that CD5 participates not only in cell-to-cell immune interactions through still poorly defined endogenous ligands expressed on hemopoietic and nonhemopoietic cells but also in recognition of exogenous and highly conserved microbial structures such as fungal β-glucans. Preceding single nucleotide polymorphism (SNP) data analysis provided evidence for a recent selective sweep in East Asia and suggested a nonsynonymous substitution at position 471 (A471V; rs2229177) of the cytoplasmatic region of the CD5 receptor as the most plausible target of selection.