Differential effects of prolactin upon activation and differentiation of human B lymphocytes.
The effects of human prolactin on enriched peripheral B lymphocytes obtained from healthy males were examined. Immunoregulation by prolactin was studied in B cells activated with either anti-IgM alone, or anti-IgM antibodies and recombinant interleukin-2 (r-IL-2), as well as control resting B cells. Expression of IL-2 receptors (IL-2R), and IgM and IgG in the culture supernatants were used as a measure of B cell activation and differentiation. Prolactin significantly synergized with IL-2 in the enhancement of surface expression of IL-2R on anti-IgM treated B cells. Although no differentiating effect was observed on resting B cells, prolactin (0.2-100 ng/ml) exhibited a dose-dependent enhancement upon both IgM and IgG secretion from B cells treated with anti-IgM and IL-2. In the absence of exogenously added IL-2 similar differentiating effect were observed in B cells treated with anti-IgM at prolactin concentrations of 0.2-10 ng/ml, but not 100 ng/ml. Thus, the present results demonstrate the modulatory effect of prolactin on activation and differentiation of anti-IgM triggered human B cells, and emphasize the importance of co-stimulatory signal mediated by IL-2 in B cell responses to high prolactin levels. These findings extend the immunoregulatory effects of prolactin, previously confirmed for T cells, to the B cell arm of the immune response, and suggest an important role of prolactin in mediating adaptation and communication between the nerve and immune systems.
Immunology Research Unit, Lady Davis Carmel Hospital, Haifa, Israel.
N
N
Lahat
A
A
Miller
R
R
Shtiller
E
E
Touby
D000328:Adult; D001402:B-Lymphocytes / Q000166:cytology* / Q000276:immunology*; D002454:Cell Differentiation; D002478:Cells, Cultured; D006801:Humans; D007074:Immunoglobulin G / Q000378:metabolism; D007075:Immunoglobulin M / Q000378:metabolism; D008213:Lymphocyte Activation; D008297:Male; D011388:Prolactin / Q000502:physiology*; D015375:Receptors, Interleukin-2 / Q000096:biosynthesis
D007074:Immunoglobulin G; D007075:Immunoglobulin M; D015375:Receptors, Interleukin-2; D011388:Prolactin