Study of the in vivo fixation of antibodies on tumors provoked in hamsters by injection of SV40‐transformed cells (TSV₅Cl₂)

Abstract

Large particle fraction obtained by the technique of Sjögren and Motet (1969) can be treated at acid pH, to elute immunoglobulins from hamster tumors induced by injection of SV‐40 transformed fibroblasts (TSV5Cl2). The eluate contains IgG27S, as well as two fragments having molecular weights of about 67,000; one of these, Fc, migrates in the β region, and the other, F(ab), migrates in the slow y region. This eluate, tested on TSV5Cl2in culture, contains some cytotoxic antibodies and antibodies against T antigen and cytoplasmic antigen.

Counteraction of the blocking of cell‐mediated tumor immunity by inoculation of unblocking sera and splenectomy: immunotherapeutic effects on primary polyoma tumors in rats

“…The appearance of a blocking serum activity, probably mediated by antigen-antibody complexes, has been implicated as partially responsible for the progressive tumor growth in individuals having cytotoxic lymphocytes although other escape mechanisms have to be considered as well (Hellstrom and Hellstrom, 1970b;Sjogren et al, 1971). This view is strengthened by the finding that blocking activity appears in the serum of animals early in the course of tumor development, sometimes even preceding the development of a detectable tumor mass (Hellstrom et al, 1970;Sjogren and Borum, 1971;Bansal and Sjogren, 1972), and that blocking activity and immunoglobulins of IgC(2) type can be eluted at low PH from the cells of tumor tissue obtained directly from tumor-bearing animals and human patients (Ran and Witz, 1970;Sjogren and Bansal, 1971 ;Sobczak and de Vaux Saint Cyr, 1971;Bansal er al., 1972;Sjogren et a l , , 1972). Furthermore, passive transfer of blocking serum or tumor eluates to animals isografted with tumor has been shown to facilitate the growth of the respective tumor grafts (Bansal ef a/., 1972;Ran and Witz, 1972).…”

Facilitation of polyoma tumor growth in rats by blocking sera and tumor eluate

“…Similar findings have been obtained when various human neoplasms were studied (Sjogren et al, 1972). It has also been reported that low PH eluates from chemically induced tumor tissue and SV40 tumor tissue contain IgG 2 but very little or no IgG 1 , which might indicate that tumor cells in vivo are coated with IgG 2 anti-tumor antibodies or antigen-antibody-complexes (Ran and Witz, 1970; Sobczak and de Vaux Saint Cyr, 1971). Although the biological activity of the eluted gamma globulin was not studied, it is quite possible that the eluted IgG 2 is associated with the blocking activity as detected in the in vitro tests.…”

Surface immunoglobulins and protease inhibitors of human acute leukemia blasts

“…Other investigators have demonstrated the presence of intact IgG, Fab fragments and Fc fragments in low PH elution of SV40-induced tumor cells in hamsters (Sobczak and de Vaux Saint Cyr, 1971). The fact that Fc fragment was not detected in any leukemic blast eluates suggests that the degradation of surface IgG occurred in vivo prior to elution of intact cells.…”

“…A major factor in understanding the host/tumor relationship has been the recent demonstration that many tumor cells also appear to be coated in vivo with immunoglobulin, particularly IgG. Indeed, most human and animal tumor cells tested thus far have been found to be coated in vivo with immunoglobulin (Sobczak and de Vaux Saint Cyr, 1971;Metzgar et al, 1975 Foulis et a/., 1973; Yoshida and Imai, 1970;Falletta et al, 1974;Gutterman et at., 1973;Cohen, 1972;Miller et al, 1974;Irie et a/., 1975). Although the immunoglobulins have been eluted from human and animal tumors (Ran and Witz, 1970;Sobczak and de Vaux Saint Cyr, 1971;Metzgar et a/., 1975;Eilber and Morton, 1970) by many investigators, the intactness and immunological reactivity of these immunoglobulins have not been clearly established.…”

“…Indeed, most human and animal tumor cells tested thus far have been found to be coated in vivo with immunoglobulin (Sobczak and de Vaux Saint Cyr, 1971;Metzgar et al, 1975 Foulis et a/., 1973; Yoshida and Imai, 1970;Falletta et al, 1974;Gutterman et at., 1973;Cohen, 1972;Miller et al, 1974;Irie et a/., 1975). Although the immunoglobulins have been eluted from human and animal tumors (Ran and Witz, 1970;Sobczak and de Vaux Saint Cyr, 1971;Metzgar et a/., 1975;Eilber and Morton, 1970) by many investigators, the intactness and immunological reactivity of these immunoglobulins have not been clearly established. The immunoglobulin coat may consist of specific anti-tumor antibodies bound to their target antigens or may be non-specific (Tonder and Thunold, 1973; Tonder ef a/., Kerbel and Davies, 1974;Witz et ale, 1972) or both.…”