Independent regulation of B-cell inducing factor and IL-2 production by T lymphocytes, and direct and indirect promotion of immunoglobulin secretion by glucocorticosteroid |
| |
Authors: | G Jeong I Nakoinz P Ralph |
| |
Affiliation: | 1. Department of Developmental Hematopoiesis, Sloan-Kettering Institute for Cancer Research, Rye, New York 10580 USA;2. Sloan-Kettering Division, Graduate School of Medical Sciences, Cornell University, New York 10021 USA;3. Department of Cell Biology, Cetus Corporation, Emeryville, California 94608 USA |
| |
Abstract: | The conditions for induction of B-cell inducing factor (BIF) by human peripheral blood T cells was investigated. BIF was assayed by induction of immunoglobulin secreting cells (ISC) in peripheral blood B (non-T) cells stimulated with Staphylococcus aureus bacteria strain Cowan I (Sac), and in the IgM cell line SKW6.4. Maximum BIF production occurred with high concentrations of the T-cell mitogens phytohemagglutinin, concanavalin A, and PWM. Dexamethasone (Dex) also induced BIF production in T cells at 10(-5) to 10(-7) M. At 10(-5) and 10(-6) M Dex, the T-cell supernatants had to be dialyzed before testing because Dex alone stimulated variable levels of ISC in both test B-cell assays. Dex did not enhance BIF production by T cells that were optimally stimulated by lectin. BIF levels were maximum by Day 2 of T-cell cultures and remained high at Days 3 and 4. In contrast, IL-2 reached a peak at Day 1 and declined drastically by Day 4. We previously showed that IL-2 at less than 100 U/ml did not induce ISC in B cells and did not alter ISC induction by BIF. Dex did not induce IL-2 production and inhibited IL-2 production induced by Con A, in contrast to the promoting effects of Dex on BIF production, providing further evidence for the independence of BIF and IL-2 production and B-cell stimulation. |
| |
Keywords: | |
本文献已被 ScienceDirect 等数据库收录! |
|