Recent reports on the CD40L gene responsible for x-linked hyper IgM syndrome
(HIM) pull together a lot of data about the cytokine control of class
switching. Two patterns emerge. IL-2, IL-10, and TGF-beta control IgG1-3 and
IgA secretion. IL-4 controls IgG4 and IgE secretion. My question concerns
IgA. Given the order of constant chain genes in the human, is the IgA in the
former case IgA1? Was IgA2 looked for in the latter case? Just wondering.
Ralph A. Sorensen
Biology Department
Gettysburg College
rsorense at gettysburg.edu
(717) 337-9171
(717) 337-6666 (fax)
