Inhibition of tumor-induced myeloid-derived suppressor cell function by a nanoparticulated adjuvant.
J Immunol
; 186(1): 264-74, 2011 Jan 01.
Article
in En
| MEDLINE
| ID: mdl-21135171
ABSTRACT
The interaction between cancer vaccine adjuvants and myeloid-derived suppressor cells (MDSCs) is currently poorly understood. Very small size proteoliposomes (VSSP) are a nanoparticulated adjuvant under investigation in clinical trials in patients with renal carcinoma, breast cancer, prostate cancer, and cervical intraepithelial neoplasia grade III. We found that VSSP adjuvant induced a significant splenomegaly due to accumulation of CD11b(+)Gr-1(+) cells. However, VSSP-derived MDSCs showed a reduced capacity to suppress both allogeneic and Ag-specific CTL response compared with that of tumor-induced MDSCs. Moreover, splenic MDSCs isolated from tumor-bearing mice treated with VSSP were phenotypically more similar to those isolated from VSSP-treated tumor-free mice and much less suppressive than tumor-induced MDSCs, both in vitro and in vivo. Furthermore, different from dendritic cell vaccination, inoculation of VSSP-based vaccine in EG.7-OVA tumor-bearing mice was sufficient to avoid tumor-induced tolerance and stimulate an immune response against OVA Ag, similar to that observed in tumor-free mice. This effect correlated with an accelerated differentiation of MDSCs into mature APCs that was promoted by VSSP. VSSP used as a cancer vaccine adjuvant might thus improve antitumor efficacy not only by stimulating a potent immune response against tumor Ags but also by reducing tumor-induced immunosuppression.
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Proteolipids
/
Sarcoma, Experimental
/
Adjuvants, Immunologic
/
Cancer Vaccines
/
Myeloid Cells
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Nanoparticles
/
Lymphoma
/
Antineoplastic Agents
Limits:
Animals
Language:
En
Journal:
J Immunol
Year:
2011
Type:
Article
Affiliation country:
Cuba