Open AccessCharacterization of immunologically significant unique B16 melanoma proteins produced in vivo and in vitro
Author(s) -
Douglas M. Gersten,
Vincent J. Hearing,
John J. Marchalonis
Publication year - 1981
Publication title -
proceedings of the national academy of sciences of the united states of america
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 5.011
H-Index - 771
eISSN - 1091-6490
pISSN - 0027-8424
DOI - 10.1073/pnas.78.8.5109
Subject(s) - in vitro , in vivo , melanoma , biology , microbiology and biotechnology , membrane protein , biochemistry , chemistry , membrane , cancer research , genetics
Proteins unique to B16 melanoma cells grown in culture and as solid tumors have been independently described recently. As both proteins have apparent M(r) of 65,000-70,000, we have more fully compared their biochemical characteristics. The M(r) 65,000 protein, which is isolated from B16 cells in culture, has an aggregate molecular weight of >200,000 under nonreducing conditions. This M(r) 65,000 form is shed into the culture medium exclusively and is the predominant molecular species of serum-free culture supernatants. It was found that B700, a major membrane protein of B16 cells in solid tumors, and the M(r) 65,000 preparation from cultured cells were electrophoretically identical when compared under four separate sets of conditions. These two proteins also share immunologic determinants. The results suggest the identity of these two proteins isolated by completely different approaches.