Article


Lung and splenic B cells facilitate diverse effects on in vitro measures of antitumor immune responses

Harlan P. Jones1,2, Yi-Chong Wang2, Beau Aldridge2 and Jay M. Weiss2

1Department of Molecular Biology and Immunology, University of North Texas Health Science Center, Fort Worth, TX, USA

2Department of Psychiatry and Behavioral Sciences, Emory University School of Medicine, Atlanta, GA, USA

Communicated by: G Dranoff

Keywords: rats, lung, spleen, B lymphocytes, MADB106, cancer, immunologic cytotoxicity


Abstract

In vitro measures of immune responsiveness toward tumors provide relevant information regarding the prevention and metastatic potential of cancer. In addition, the compartmentalization of immune responses is likely to be an important factor in dictating host antitumor immune responses. We have previously demonstrated that injection of antibody against B cells diminished pulmonary antitumor defenses. In the current study, we determined the effect of B cells on antitumor cellular responses against a lung metastatic tumor, MADB106. Lung B cells displayed sustained surface expression of CD80 and CD86, as compared to spleen B cells, in the presence of MADB106 tumor. Removal of B cells from lung lymphocyte cultures resulted in diminished IFN-γ secretion and tumor lysis, whereas removal of B cells from spleen lymphocytes exposed to tumor resulted in elevated IFN-γ and increased tumor lysis. Furthermore, a correlative increase in CD80 and CD86 co-stimulatory molecule expression by lung B cells was observed in mice subjected to MADB106 tumor. These findings provide additional evidence of the importance of pulmonary B cell responses in tumor defenses.