The Sheep Erythrocyte Receptor and Both α and β Chains of the Human T‐Lymphocyte Antigen Receptor Bind the Mitogenic Lectin (Phytohaemagglutinin) from Phaseolus vulgaris

摘要: We have studied the interaction of mitogenic lectins such as phytohaemagglutinin (PHA) and concanavalin A (Con A) with both surface molecules which, by use monoclonal antibodies, are known to trigger T-cell mitogenesis. Monoclonal antibodies recognizing T-lymphocyte receptor for antigen (Ti) and/or its associated structure, CD3, activate T cells. More recently, a second pathway activation has been described which involves sheep erythrocyte binding glycoprotein CD2, molecule distinct from Ti-CD3. Lysates surface-iodinated T-leukaemia cell lines were treated lectin affinity purified anti-lectin coupled protein A-Sepharose. shown that eluates Con A/anti-Con or PHA/anti-PHA immunoprecipitates contained Ti, since rabbit anti-T alpha serum, recognizes native denatured forms constant region chain, immunoprecipitated Ti these eluates. Furthermore, serum lysates iodinated E+ lymphocytes was PHA after elution immunoprecipitate. When reduced alkylated, allowing permanent dissociation beta subunits, interacted chains, whereas chain only. Altogether, results demonstrate interacts chains on human peripheral lymphocytes. With HPB-ALL tumour line, similar approach showed bind Ulex europaeus 1 but not Helix pomatia. Affinity chromatography immobilized immunoprecipitation lectin/anti-lectin employed test whether CD2 binds A. The show lower than