AbstractsBiology & Animal Science

Antibody synthesis in vitro has been studied wtth immunologically competent cells of lymphoid tissue in radioactive culture medium. Specific antibody proteins have been isolated and characterized from such a system. However, non-specific radioactive proteins which coprectpitated with heterologous precipitates were also found in the culture medium (Ketson and Katchen, 1956; Wolf and Stavitsky, 1958; Stavitsky 1958, 1960, 1961; Dutton et al., 1958; Askonas and Humphrey, 1958; Vaughan et al., 1960; Bussard and Huynh, 1960; and Thorbecke, 1960). The so-called non-specific proteins were produced by normal and immunologically competent cells; they had the capacity to absorb to antigen-antibody complexes and were found in the alpha and beta globulin protein fractions. These properties suggested that such non-specific proteins might be complement. In this laboratory, non-specific coprecipitating proteins were also found to be present in culture medium in which immunologically competent cells were Incubated. This observation,as well as those previously mentioned, initiated this investigation in order to determine whether or not these non-specific proteins were identlcal with complement and also to identify the tissues concerned with the synthesis. [...]