CVID6 due to CD81 D84.8

CVID6 with mutation in CD81 is an immunodeficiency syndrome caused by a homozygous mutation in the CD81 gene (186845) on chromosome 11p (van Zelm MC et al. 2010).

Van Zelm et al (2010) reported on a 6-year-old Moroccan girl born to consanguineous parents who suffered from recurrent respiratory infections during the first two years of life. At the age of 3.5 years, she developed acute glomerulonephritis with proteinuria, vasculitic purpura (leukocytoclastic vasculitis), and arthralgias associated with deposits of IgA and C3 (120700), leading to renal failure. She also had hepatomegaly and thrombocytopenia associated with platelet antibodies.

Laboratory tests showed hypogammaglobulinemia with decreased IgG, low to normal IgA, and normal IgM. There was no detectable antibody response to tetanus or pneumococcal antigens. Flow cytometric studies revealed normal levels of B, T, and NK cells. However, the B cells did not express CD19 (107265) or CD81. The number of memory B cells was decreased. See also CVID3 (613493) (Van Zelm et al. 2010).

1. Cherukuri A et al (2004) B cell signaling is regulated by induced palmitoylation of CD81. J Biol Chem 279:31973-31982.
2. Rocha-Perugini Vet al (2013) CD81 controls sustained T cell activation signaling and defines the maturation stages of cognate immunological synapses. Mol Cell Biol 33:3644-3658.
3. Takeda Y et al (2003) Tetraspanins CD9 and CD81 function to prevent the fusion of mononuclear phagocytes. J Cell Biol 161:945-956).
4. van Zelm MC et al (2010) CD81 gene defect in humans disrupts CD19 complex formation and leads to antibody deficiency. J Clin Invest 120:1265-1274