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Adherence of murine t cells to solid substrata in the absence of serum

It is generally assumed that lymphocytes do not adhere firmly to solid substrata. However, in attempting to culture murine spleen and thymus cells in RPMI 1640 without serum, we observed that some cells adhered to glass or plastic surfaces. As a minimum estimate, 10–12% of the applied spleen cells and 22% of those from thymus attached between 1 and 24 hours after plating. The cells remained attached despite extensive and vigorous washing. Viability of 70% was maintained between 4 hours and 3 days in culture. Readdition of 10% mouse or horse serum for 2 hours resulted in removal of 80% of the attached cells. The percentage of adherent cells was not affected by cell density, but was greatly reduced when cells were cultured at 4 °C. Glutaraldehyde‐fixed cells did not adhere. Adherent cells were primarily T lymphocytes. The cell‐plate distance would indicate a focal contact mode of adherence; however, the absence of filamentous material at the adherent surface and the broad, continuous surface apposition would imply a close contact mode. We conclude that attachment modes described for fibroblasts in culture are not applicable for lymphocytes.