Differential expression and regulation of cytokine mRNAs in normal human CD45R T cell subsets.
Cytokine mRNA expression was analyzed by reverse transcriptase (RT)/PCR in extensively purified normal peripheral CD4+CD45R T cell subsets. Both CD45RA+ and CD45 RO+ populations produced mRNAs for interleukin (IL)-2, IL-2 receptor (alpha chain), IL-6 receptor and tumour necrosis factor (TNF)-beta within 3-4 h of activation. Whilst IL-3 and RANTES were also expressed in both subsets, CD45RO+ cells were clearly the major producers of these cytokines. In contrast, mRNA transcripts for IL-1 alpha, IL-4, IL-5, IL-6, IL-10, interferon gamma (IFN-gamma) and the T cell receptor for IL-1 were almost exclusively induced in CD45RO+ T cells. A population of CD4+ T cells co-expressing intermediate levels of both CD45RA and CD45RO, namely CD45RA+/CD45RO+, appeared to be the major producers of IL-6. Addition of cycloheximide (CHx) 4 h after T cell activation resulted in substantial superinduction of IL-2 mRNA in the CD4+CD45RO+ population but had little effect on CD4+CD45RA+ cells. Taken together, these results show that normal CD4+CD45R T cell subsets exhibit distinct cytokine mRNA profiles and that these differ from the patterns displayed by Th1 and Th2 type T helper clones. Furthermore, they suggest for the first time that IL-2 mRNA turnover is differentially regulated in CD45R T cell subsets.
Beckman
I
I
Department of Clinical Immunology, Flinders Medical Centre, Bedford Park, South Australia.
Shepherd
K
K
Dimopoulos
K
K
Ahern
M
M
Firgaira
F
F
Bradley
J
J
D000328:Adult; D001483:Base Sequence; D002478:Cells, Cultured; D003513:Cycloheximide / Q000494:pharmacology; D017931:DNA Primers; D005434:Flow Cytometry; D006801:Humans; D007371:Interferon-gamma / Q000096:biosynthesis* / Q000097:blood; D007372:Interferons / Q000096:biosynthesis* / Q000097:blood; D017493:Leukocyte Common Antigens / Q000097:blood*; D008213:Lymphocyte Activation; D008969:Molecular Sequence Data; D016133:Polymerase Chain Reaction / Q000379:methods; D016176:T-Lymphocyte Subsets / Q000187:drug effects / Q000276:immunology / Q000378:metabolism*
D017931:DNA Primers; D007371:Interferon-gamma; D007372:Interferons; D003513:Cycloheximide; D017493:Leukocyte Common Antigens