Cytokine mRNA expression during an in vitro response of human B lymphocytes: kinetics of B cell tumor necrosis factor alpha, interleukin (IL)6, IL-10, and transforming growth factor beta 1 mRNAs.
Expression of mRNA for eight cytokines was analyzed in an in vitro response-proliferation and Ig-secretion--of normal human B lymphocytes. This was made possible by the use of murine thymoma cells as helper cells in conjunction with human T cell supernatant, and the design of human DNA sequence-specific primers for RT-polymerase chain reaction. mRNAs for interleukin (IL)2 and IL-4, but also for IL-1 alpha and IL-1 beta remained undetectable during the whole culture period in highly purified B cells prepared by a three-step purification protocol. However, tumor necrosis factor alpha and IL-6 mRNAs peaked during days 1-3 after culture start and became undetectable after 5-6 d, shortly before bulk B cell proliferation started to decline. In contrast, transforming growth factor beta 1 mRNA, after a progressive increase during the first few days, and IL-10 mRNA, after a peak on days 1-3, remained detectable in immunoglobulin (Ig)-secreting cultures throughout the observation period of 22 d. Clonal analysis on 8-d cultures that had been seeded with single B cells by autocloning with the cell sorter, revealed that 85% of 77 B cell clones studied, expressed TGF-beta 1 mRNA, and only 19% IL-10 mRNA. These findings show a differentiation stage-related cytokine program during a B cell response, whereby (a) B cells can become activated without IL-1 alpha or IL-1 beta expression; (b) mRNA for positive (IL-10) and negative (TGF-beta 1) autoregulatory factors coexists in cell populations during the later phase of the response, although not necessarily in all B cell clones; and (c) normal Ig-secreting cells cease IL-6 expression in contrast to their malignant counterparts, myeloma cells.
Matthes
T
T
Department of Medicine, Geneva University Hospital, Switzerland.
Werner-Favre
C
C
Tang
H
H
Zhang
X
X
Kindler
V
V
Zubler
R H
RH
D015703:Antigens, CD / Q000235:genetics; D000945:Antigens, Differentiation, T-Lymphocyte / Q000235:genetics; D001402:B-Lymphocytes / Q000166:cytology / Q000378:metabolism*; D001483:Base Sequence; D018801:CD2 Antigens; D002454:Cell Differentiation; D002478:Cells, Cultured; D002999:Clone Cells; D016207:Cytokines / Q000235:genetics*; D004277:DNA, Single-Stranded; D006801:Humans; D016753:Interleukin-10 / Q000235:genetics; D015850:Interleukin-6 / Q000235:genetics; D007700:Kinetics; D008969:Molecular Sequence Data; D016133:Polymerase Chain Reaction; D012333:RNA, Messenger / Q000378:metabolism*; D011971:Receptors, Immunologic / Q000235:genetics; D016212:Transforming Growth Factor beta / Q000235:genetics; D014407:Tumor Cells, Cultured; D014409:Tumor Necrosis Factor-alpha / Q000235:genetics
D015703:Antigens, CD; D000945:Antigens, Differentiation, T-Lymphocyte; D018801:CD2 Antigens; D016207:Cytokines; D004277:DNA, Single-Stranded; D015850:Interleukin-6; D012333:RNA, Messenger; D011971:Receptors, Immunologic; D016212:Transforming Growth Factor beta; D014409:Tumor Necrosis Factor-alpha; D016753:Interleukin-10