Staining and fluorescence-activated cell sorter analysis of human lymphocytes using antibodies to a short, chemically synthesized human IL-2 peptide.
A rabbit antibody against a chemically synthesized peptide (p84), encompassing residues 59-72 of mature human interleukin 2 (IL-2), has been shown to react specifically with natural or recombinant IL-2. This antibody was used in immunoperoxidase and immunofluorescence techniques for identification of IL-2-containing cells in human peripheral blood or tonsils. Lymphocytes were stimulated with T-cell mitogens (PHA, PWM), fixed, and incubated with affinity-purified anti-p84 antibody, followed by appropriately conjugated secondary antibodies. FACS analysis demonstrated a low fluorescence intensity in 5 to 15% of unstimulated cells. In contrast, 40-60% of mitogen-stimulated cells were stained at a high fluorescence intensity. Staining was inhibited by preincubating the anti-p84 antibody with the homologous peptide or recombinant IL-2, but not by unrelated peptides. In immunoperoxidase staining, anti-p84 antibody reacted selectively with an enriched T-cell population which was 95% Leu 5+, 80% Leu 3+, and 60% Tac+. Thus, this antibody to a synthetic IL-2 peptide reacts selectively with activated T cells, and may serve, therefore, as a useful tool for visualization and enumeration of IL-2-containing cells in blood and tissues.
D000818:Animals; D000906:Antibodies / Q000276:immunology*; D002469:Cell Separation / Q000379:methods*; D005455:Fluorescent Antibody Technique; D006801:Humans; D007106:Immune Sera / Q000276:immunology; D007124:Immunoenzyme Techniques; D007376:Interleukin-2 / Q000276:immunology*; D008214:Lymphocytes / Q000276:immunology*; D010446:Peptide Fragments / Q000276:immunology*; D011817:Rabbits / Q000276:immunology
D000906:Antibodies; D007106:Immune Sera; D007376:Interleukin-2; D010446:Peptide Fragments; C046516:interleukin-2 (59-72)