Effects of transforming growth factor beta on immunoglobulin production in cultured rat lacrimal gland tissue fragments.

The effects of transforming growth factor-beta (TGF-beta) and TGF-beta in combination with selected interleukins (ILs) on immunoglobulin production was investigated using an in vitro rat lacrimal gland tissue-fragment culture system. TGF-beta alone or in combination with either IL-2, IL-5, IL-6, or IL-5 and IL-6 together significantly increased IgA levels over those obtained in untreated cultures. In all cases, IgA production was greater in cultures treated with TGF-beta in combination with these ILs than in cultures treated with TGF-beta or IL alone. The levels of IgG and IgM were generally not affected, with the exception of an enhancement noted in cultures treated with IL-5 and IL-6 or in combination with TGF-beta. These data indicate that TGF-beta can exert a stimulatory effect with IL-2, IL-5, IL-6, or IL-5 and IL-6 on IgA production in vitro and support a potential regulatory role for these cytokines in lacrimal gland IgA responses.