Competition radioimmunoassay for mason‐pfizer monkey virus: Comparison with recent isolates

Abstract

The major core protein of Mason-Pfizer monkey virus was purified by DEAE ion exchange column chromatography and shown to be 27,000 daltons (p27). Following the characterization of monospecific antisera prepared against p27, a radioimmunoassay was developed with these reagents and competition experiments were done with come of the recent M-PMY-like isolates as well as with other oncornaviruses. Results suggest that three of the viruses tested, AO, X-381 and FTP-1, are similar to M-PMV while J-96 virus is related, but not identical, to M-PMV. It is also shown that competition RIA can be used successfully to detect the presence of viral proteins in tissue homogenates and cell extracts.

Radioimmunoassay for intact Gross mouse leukemia virus.

“…Since that time several groups have described RIAs for purified core or structural virus proteins (6)(7)(8)(9)(10)(11)(12)(13)(14). This approach does have certain advantages.…”

“…Since then there has been increasing interest in the application of this methodology in a variety of investigations in virology. Most of these have been concerned with the development of sensitive radioimmunoassays for the protein components of RNA C-type oncogenic viruses, i.e., the core proteins from mammalian (6)(7)(8)(9)(10)(11)(12)(13) and avian species (14) (generally less than 30,000 daltons) and mammalian membrane glycopeptides (about 70,000 daltons) (13), which appear to be elements of the viral envelope. Some (15,16) have been developed for the assay of intact mouse mammary tumor virus.…”

Detection of an Antigen Related to Mason-Pfizer Virus in Malignant Human Breast Tumors

“…The fractions of the column where M-PMV p27 would normally be eluted were collected, concentrated, and used as competing antigens in RIA for M-PMV p27 and simian sarcoma virus (SSV-1) p30 proteins (8). 7 Of 18 breast tumor specimens that were tested, 8 induced the release of > 25 percent of the maximum precipitable '1I-labeled M-PMV p27 (Fig. 1) Competing antigen (Mg) proteins in the tumor tissues are similar to M-PMV p27.…”

“…Antigens related to the p30 protein of primate type C viruses were also found in peripheral white blood cells of patients suffering from acute leukemia (6). Recently, our laboratory has developed a specific RIA for the major structural protein (p27) of M-PMV (7). We used this assay to look for the presence of proteins related to M-PMV p27 in various types of human tissues.…”

“…Tissues were homogenized and extracted with ether to remove the lipids and fats (4). The soluble proteins contained in the aqueous phase were further purified by diethylaminoethyl (DEAE)-cellulose ion exchange column chromatography as described for M-PMV p27 (7). The fractions of the column where M-PMV p27 would normally be eluted were collected, concentrated, and used as competing antigens in RIA for M-PMV p27 and simian sarcoma virus (SSV-1) p30 proteins (8).…”