Cellular and molecular characterisation of the hyper immunoglobulin M syndrome associated with congenital rubella infection.
BACKGROUND
The hyper-immunoglobulin M syndrome (HIM) is a rare group of immune deficiency disorders characterised by normal or increased serum IgM with normal or reduced IgG, IgA and IgE.


METHODS
We have undertaken detailed cellular and molecular studies in a 53-year-old man with HIM as a result of congenital rubella.


RESULTS
No mutations were detected in the CD40 ligand, activation-induced cytidine deaminase and uracil DNA glycosylase. His T-cell responses to lectins and antigens were normal. Flow cytometry confirmed the presence of CD40 ligand on activated T cells. Most CD40-dependent functions that were tested, including B-cell proliferation, isotype switching and production of memory B cells, were normal. CD40/IL4 dependent rescue from anti-IgM-induced apoptosis was impaired.


CONCLUSIONS
The detection of cell-surface IgG but lack of serum IgG indicated that he may have an antibody secretion defect.
Ameratunga
Rohan
R
Department of Virology & Immunology, Auckland City Hospital, Auckland, New Zealand. rohana@adhb.govt.nz
Woon
See-Tarn
ST
Koopmans
Wikke
W
French
John
J
D001402:B-Lymphocytes / Q000276:immunology / Q000378:metabolism / Q000821:virology; D023201:CD40 Ligand / Q000276:immunology / Q000378:metabolism*; D006801:Humans; D053306:Hyper-IgM Immunodeficiency Syndrome / Q000097:blood / Q000150:complications / Q000276:immunology*; D007075:Immunoglobulin M / Q000097:blood*; D007156:Immunologic Memory; D008297:Male; D008875:Middle Aged; D012409:Rubella / Q000150:complications* / Q000151:congenital / Q000276:immunology; D013601:T-Lymphocytes / Q000276:immunology / Q000378:metabolism / Q000821:virology
D007075:Immunoglobulin M; D023201:CD40 Ligand