Solubilized tsta and the major viral structural proteins, gp70 and p30, in the immune response to murine leukemias induced by friend and rauscher virus

The possibility that some or all of the viral proteins, gp70, p30, and the histocompatibility antigen, H-2, function as the tumor-specific transplantation antigen (TSTA) of the R-MuLV-induced leukemia, RBL-5, and also in the secondary in vitro induction of cytotoxic T lymphocytes (CTL), was investigated. The antigen was obtained by isolating the plasma membranes of RBL-5 cells and solubilizing with sodium deoxycholate (DOC) followed by gel filtration chromatography. A fraction containing excellent tumor-rejection activity but low amounts of gp70, p30 and H-2 was chromatographed on goat anti-gp 70 goat anti-p 30 and sheep anti-H-2b immunoaffinity columns. The data obtained indicate that gp 70, p 30 or H-2 do not function as TSTA of RBL-5 leukemia, individually or as a complex. Similarly, the antigen responsible for the specific secondary induction of CTL in vitro is distinct from these three proteins.

mentioning

confidence: 92%

Rauscher leukemia virus‐induced tumor antigens: Complete separation from gp70, p30 and H‐2

Alaba

Rogers

Law

1979

“…The data clearly show no evidence of reactivity with any of these cells. It is clear that the syngeneic antiserum described here, produced by hyperimmunization with solubilized, purified membrane antigens, differs from that described and characterized previously (Rogers et al, 1977). The previous syngeneic antiserum was produced by hyperimmunizing CBFl mice with crude plasma membranes of RBL-5 and was characterized as being directed against a viral protein, probably p15E.…”

Section: Discussionmentioning

confidence: 73%

Induction and specificity of syngeneic antiserum against rauscher murine leukemia virus‐induced leukemia, RBL‐5

Alaba¹,

Law²

1980

Plasma membranes purified from RBL-5 leukemia cells and solubilized with Na deoxycholate were fractionated on an Ultrogel AcA34 column. Fractions containing most of the tumor-rejection activity but low amounts of gp70 and p30 were consolidated and used to hyperimmunize semisyngeneic, CBF1, hybrid mice. Using the complement-dependent cytotoxicity assay, we determined the antibody titers against RBL-5 and several other leukemic cells. Only RBL-5 and EL-4 tumor cells were lysed. Similar results were obtained when the same tumor cells were used to absorb the syngeneic antiserum and the residual cytotoxic titer determined on RBL-5 target cells. Coupling of the gamma-globulins from this antiserum to Sepharose 4B facilitated the isolation of an antigen which inhibited the C'-dependent lysis of RBL-5 tumor cells and, when used for immunization, protected the recipient mice against a subcutaneous challenge of RBL-5 leukemia cells. By means of disc gel electrophoresis, in the presence of SDS and 2-mercaptoethanol, two polypeptide chains with molecular weights of 46,000 and 21,000 were resolved. The binding of the antigen to a lens culinaris lentil lectin column and its subsequent elution with alpha-methyl mannoside suggests that the specific tumor antigen is a glycoprotein.

“…Such antigens have been described for the avian leukosis-sarcoma system (Rogers et al, 1978) and for feline leukemia virus-induced tumors (Stephenson et al, 1977). With FMR tumors, Law and Apella (1973) first reported the isolation from RBL-5 of a TATA (Mol.…”

Section: Discussionmentioning

confidence: 99%

“…The most intriguing question in the study of TASA in MuLV-induced tumor systzms has been whether these include tumor-associated antigens distinct from virion components. Such antigens have been described for the avian leukosis-sarcoma system (Rogers et al, 1978) and for feline leukemia virus-induced tumors (Stephenson et al, 1977). With FMR tumors, Law and Apella (1973) first reported the isolation from RBL-5 of a TATA (Mol.…”

Section: Discussionmentioning

confidence: 99%

Immunochemical characterization of tumor‐associated surface antigens on a moloney leukemia virus‐lymphoma, MBL‐2

McIntire

Suzuki³

et al. 1979

Tumor-associated surface antigens (TASA) on a Moloney leukemia virus (M-MuLV)-induced lymphoma, MBL-2, in C57BL/6 mice (B6) were characterized. The surface proteins of MBL-2 cells were selectively radioiodinated and then extracted by Nonidet P40. The solubilized materials were then reacted with a variety of antisera: monospecific antisera to murine leukemia viral proteins (anti-gp69/71, anti-p30, anti-p15, anti-p12 and anti-p10), sera from B6 which regressed murine sarcoma tumors induced by murine sarcoma virus (anti-MSV) and a rabbit anti-MBL-2 antiserum. The resulting radioimmune precipitates were analyzed and compared in sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). The following results were obtained. (1) Among all anti-viral protein antisera tested only anti-gp69/71 was active and detected a protein doublet of gp69/71 and its degradation fragments of 42,000 and 35,000 daltons. (2) Radioimmune precipitates prepared with anti-MSV showed a SDS-PAGE pattern similar to that seen with anti-gp69/71. This result indicated that the surface antigen detected by the anti-MSV serum on MBL-2 tumor cell was probably a viral envelope antigen. (3) The rabbit anti-MBL-2 serum detected on the cell membrane an antigen of approximately 95,000 daltons which was tumor-associated and did not appear to be related to virion components. The anti-MBL-2-serum still reacted with the 95,000 dalton antigen after absorption with disrupted M-MuLV virus and with gp69/71 and p30 purified from the virus.