T lymphocytes in rat germinal centres belong to an ER3+ subpopulation of CD4+ cells.
Two-colour immunofluorescence histochemistry showed directly that greater than 90% of CD4+ germinal centre T cells in rat spleen or lymph node examined 7 days after immunization bear the antigen recognized by the monoclonal antibody (mAb) ER3. By contrast, only 30-40% of all thoracic duct or lymph node CD4+ cells were ER3+, as determined by two-colour flow cytometry. CD8+ cells were ER3+, but nearly all B cells were ER3-. Thus, germinal centre T cells belong to a subpopulation of CD4+ cells. Because only 25-30% of CD4+ cells that lack higher molecular weight forms of CD45 (i.e. mAb MRC OX32 cells, equivalent to MRC OX22 cells) express ER3, the CD4+ subpopulations defined by ER3 are neither identical nor complementary to the subsets defined by restricted expression of CD45 epitopes.
Vonderheide
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RH
Sir William Dunn School of Pathology, Oxford University.
Hunt
S V
SV
D000818:Animals; D015704:CD4 Antigens / Q000032:analysis*; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology*; D005455:Fluorescent Antibody Technique; D007958:Leukocyte Count; D008198:Lymph Nodes / Q000276:immunology*; D051381:Rats; D013154:Spleen / Q000276:immunology*
D015704:CD4 Antigens