Effective anti-tumor immunity induced in mice by a two-step vaccination protocol.
BACKGROUND
TS/A cells (a Balb/c-derived tumor cell line), when injected into syngenic mice, give rise to rapidly growing tumors. In this study, a vaccination protocol was established which was able to elicit an immune response effective in controlling tumor growth.


METHODS
T19.2.1, a TS/A clone enginereed to stably express the mycobacterial cell wall-associated 19-kDa lipoprotein, was used as cell vaccine to immunize Mycobacterium Bovis-BCG pre-immunized Balb/c mice.


RESULTS
Mice receiving the two-step vaccination protocol were able to develop a strong anti-TS/A DTH reaction. Moreover, following a challenge with wild-type TS/A cells, some vaccinated animals rejected the tumor and the remaining animals showed a significantly increased survival in respect to controls.


CONCLUSIONS
The expression on TS/A cells of the mycobacterial 19-kDa antigen, recognised in the context of a pre-existing memory immune response, promotes the immunological recognition of the otherwise non-immunogenic wild-type TS/A cells.
Martino
A
A
Department of Biology, University of Tor Vergata, Via della Ricerca Scientifica s.n.c., 00133 Rome, Italy. Martino@Scienze.uniroma2.it
Vismara
D
D
Cicconi
R
R
Delpino
A
A
Ivanyi
J
J
Colizzi
V
V
Cassol
M
M
Fraziano
M
M
Piselli
P
P
D000230:Adenocarcinoma / Q000276:immunology* / Q000628:therapy; D000818:Animals; D001500:BCG Vaccine / Q000008:administration & dosage*; D001426:Bacterial Proteins / Q000008:administration & dosage / Q000235:genetics / Q000276:immunology*; D019496:Cancer Vaccines / Q000008:administration & dosage*; D002999:Clone Cells / Q000276:immunology / Q000637:transplantation; D005240:Feasibility Studies; D005260:Female; D006084:Graft Rejection; D006968:Hypersensitivity, Delayed / Q000209:etiology / Q000276:immunology; D007114:Immunization / Q000379:methods*; D007156:Immunologic Memory; D008325:Mammary Neoplasms, Experimental / Q000276:immunology* / Q000628:therapy; D051379:Mice; D008807:Mice, Inbred BALB C; D009368:Neoplasm Transplantation; D014162:Transfection; D014407:Tumor Cells, Cultured / Q000276:immunology / Q000637:transplantation
C087864:19 kDa antigen, Mycobacterium; D001500:BCG Vaccine; D001426:Bacterial Proteins; D019496:Cancer Vaccines