Role of recombinant interleukin-1 compared to recombinant T-cell replacing factor/interleukin-5 in B-cell differentiation.
The B-cell differentiation-inducing activity of interleukin-1 (IL-1) was compared with that of T-cell replacing factor (TRF)/interleukin-5 (IL-5), which was originally described as a late-acting B-cell differentiation-inducing factor. Human recombinant IL-1 and murine recombinant TRF/IL-5 were used in this study. Purified B cells from non-primed or antigen-primed mice, LPS-stimulated B-cell blasts, and chronic B-cell leukaemia (BCL1) cells were used as the responding B-cell population. Addition of IL-1 to the culture of normal B-cells and sheep red blood cells (SRBC) induced a dose-dependent anti-SRBC IgM response, with maximal response at 100 U/ml, whereas the response induced by TRF/IL-5 was less than that induced by IL-1 and did not reach the maximum even at 100 U/ml. Addition of anti-IL-1 antibody, but not anti-TRF/IL-5 antibody or anti-IL-2 receptor antibody, inhibited IL-1-induced anti-SRBC responses. Depletion of cells adherent to Sephadex beads from splenic B cells showed no significant effect on the magnitude of the total responses. IL-1 could induce little, if any, differentiation in antigen-primed B cells, LPS-stimulated B-cell blasts, or BCL1 cells into antibody-secreting cells, whereas differentiation could be induced by low doses of TRF/IL-5 (1-2 U/ml). Of great interest is that suboptimal doses of IL-1 (10 U/ml) could synergize with TRF in the primary anti-SRBC PFC responses. Kinetic studies revealed that IL-1 acts on B cells for the first 2 days and TRF/IL-5 for the last 3 days in 5-day cultures of B cells. These results suggest that IL-1 acts primarily on resting B cells as a differentiation-inducing factor in the presence of antigen, and also acts as a 'priming' factor for TRF/IL-5.
Koyama
N
N
Department of Biology, Kumamoto University Medical School, Japan.
Harada
N
N
Takahashi
T
T
Mita
S
S
Okamura
H
H
Tominaga
A
A
Takatsu
K
K
D000276:Adjuvants, Immunologic / Q000494:pharmacology; D000818:Animals; D000917:Antibody Formation; D000921:Antibody-Producing Cells / Q000276:immunology; D000944:Antigens, Differentiation, B-Lymphocyte / Q000276:immunology; D001402:B-Lymphocytes / Q000166:cytology*; D002454:Cell Differentiation / Q000187:drug effects; D002478:Cells, Cultured; D004306:Dose-Response Relationship, Immunologic; D006462:Hemolytic Plaque Technique; D006801:Humans; D007075:Immunoglobulin M / Q000096:biosynthesis; D007375:Interleukin-1 / Q000494:pharmacology*; D015848:Interleukin-5; D007378:Interleukins / Q000494:pharmacology*; D007700:Kinetics; D051379:Mice; D008815:Mice, Inbred Strains
D000276:Adjuvants, Immunologic; D000944:Antigens, Differentiation, B-Lymphocyte; D007075:Immunoglobulin M; D007375:Interleukin-1; D015848:Interleukin-5; D007378:Interleukins