Combined Vaccine Strategy Boosts Antitumor Immunity In Mice.(Brief Article)

2001 AUG 8 - (NewsRx.com & NewsRx.net) --

by N.R. Saltmarsh, staff medical writer - A new report in Cancer Research describes a combined vaccine strategy that improved survival and antitumor response in mice with liver cancer.

D.W. Grosenbach and colleagues at the U.S. National Institutes of Health tried several vaccine strategies alone and in combination in an attempt to amplify T-cell responses using carcinoembryonic antigen (CEA), in both conventional and transgenic mice that expressed CEA in tissue and sera.

Their findings were as follows:

* A recombinant avipox vector (rF) expressing CEA and the B7-1 costimulatory molecule transgenes (designated rF-CEA/B7-1) is more potent in inducing CEA-specific T-cell responses than rF-CEA

* One administration of rF expressing CEA and three different costimulatory molecule transgenes (B7-1, ICAM-1, LFA-3, designated rF-CEA/TRICOM) was more potent in inducing CEA-specific T-cell responses than four vaccinations with rF-CEA or two vaccinations with rF-CEA/B7-1, and up to four vaccinations with rF-CEA/TRICOM induced greater T-cell responses with each vaccination

* A prime with a recombinant vaccinia vector expressing CEA and the triad of costimulatory molecules (designated rV-CEA/TRICOM) and a boost with rP-CEA/TRICOM was more potent in inducing CEA-specific T-cell responses than the repeated use of rF-CEA/TRICOM alone