[Effects of two different antigen-loading methods on the activity of dendritic cell vaccine for colorectal carcinoma cell inhibition in vitro].
OBJECTIVE
To observe the changes in the activity of dendritic cells (DCs) after carcino-embryonic antigen (CEA) gene transfection mediated by recombinant adeno-associated virus type2 (rAAV) and tumor cell lysate.


METHODS
Immature DCs isolated from peripheral blood monocytes of HLA-A11-positive healthy volunteers were infected with the rAAV carrying CEA gene or loaded with tumor cell lysate. The surface markers of the DCs such as CD40, CD 1alpha, and CD86 were analyzed by flow cytometry. Interleukin-12 (IL-12) in the supernatants of DCs and interferon-gamma (IFN-gamma) released by the cytotoxic T lymphocytes (CTLs) were determined by ELISA detection kit. The specific killing activity of CTL against LoVo cells was assessed by MTT assay.


RESULTS
The DCs following antigen loading with the two methods both highly expressed CD40, CD86 and IL-12, and induced specific CTL that specifically recognized and killed LoVo cells, but the killing effect resulting from rAAV infection of the DCs was much better than that induced by tumor cell lysate loading.


CONCLUSIONS
Both methods of antigen loading can induce mature DCs from peripheral blood monocyte cells, but rAAV infection of the DCs can be more effective than tumor cells lysate loading. DCs infected with rAAV may have the potential to serve as an adjuvant immunotherapy for patients with colorectal carcinoma.
Huang
Hao
H
Oncology Center, Nanfang Hospital, Southern Medical University, Guangzhou 510515, China.
Wang
Hang
H
Wu
Zi-qing
ZQ
You
Chang-xuan
CX
Luo
Rong-cheng
RC
Yong
Liu
L
Hermonat
Paul L
PL
D051940:B7-2 Antigen / Q000378:metabolism; D019013:CD40 Antigens / Q000378:metabolism; D019496:Cancer Vaccines / Q000096:biosynthesis* / Q000276:immunology*; D002272:Carcinoembryonic Antigen / Q000235:genetics; D045744:Cell Line, Tumor; D015179:Colorectal Neoplasms / Q000628:therapy*; D003713:Dendritic Cells / Q000276:immunology* / Q000378:metabolism; D000229:Dependovirus / Q000235:genetics; D005822:Genetic Vectors; D006801:Humans; D018664:Interleukin-12 / Q000378:metabolism; D014162:Transfection
D051940:B7-2 Antigen; D019013:CD40 Antigens; D019496:Cancer Vaccines; D002272:Carcinoembryonic Antigen; D018664:Interleukin-12