Antigenic strength investigated by cell‐mediated lympholysis in mice

Abstract

Abstract The cell‐mediated lympholysis (CML) technique has been used to investigate antigenic strength in mice. Investigations of the parameters of the technique led to calculation of specific chromium release on the basis of the effect of 5‐day mixed lymphocyte cultures (MLC) incubated for 4 h with 3‐day 51 Cr‐labeled phytohemagglutinin (PHA) transformed blast cells in a ratio of 50:1. The specificity of the reaction was established in mirror experiments and both major histocompatibility locus and M‐locus (non H‐2) incompatible MLC were tested against the appropriate PHA blasts. While strong MLC stimulation occurred in both these types of incompatible combinations, a specific killing capacity for CML developed only in the former. Furthermore, M‐locus gene products per se do not seriously influence the outcome of allograft survival a result consistent with those of others working in the rat and man, in which species the capacity to respond in MLC and to kill in CML and/or to reject allografts can be separated. The fact that M‐locus stimulation does not lead to cell killing could be due to the absence of a concomitant serologically defined incompatibility; if so, the serologically undetectable lymphocyte activating determinants of the major histocompatibility system linkage group could have a similar biological function to that of the M‐locus.