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.
Lahat
N
N
Immunology Research Unit, Lady Davis Carmel Hospital, Haifa, Israel.
Miller
A
A
Shtiller
R
R
Touby
E
E
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