Combined treatment with intratumoral injection of dendritic cells and topical application of imiquimod for murine melanoma.
BACKGROUND
The maturation state of dendritic cells is one of the factors that affect their capacity to induce antigen-specific cytotoxic T lymphocytes. Topical cutaneous application of imiquimod can induce the maturation and migration of cutaneous dendritic cells.


OBJECTIVE
To evaluate the synergistic effect of topical application of imiquimod plus intratumoral injection of syngeneic bone marrow-derived dendritic cells in the treatment of melanoma.


METHODS
For the B16F10 melanoma model, naive C57BL/6 mice were inoculated intradermally with 2x10(3) B16F10 melanoma cells in the right upper flank. Four groups (untreated control, dendritic cells alone, imiquimod alone and imiquimod plus dendritic cells) were included in the animal study, with five mice in each group. Tumour size was measured every 2 weeks, and histochemical and immunohistochemical staining carried out. ELISpot and PKH assays were performed to assess immune activity.


RESULTS
Combined treatment of topical application of imiquimod and intratumoral injection of dendritic cells led to significant tumour regression, in contrast to partial eradication of the tumours with imiquimod or dendritic cells alone.


CONCLUSIONS
These findings suggest that combination therapy with topical application of imiquimod and intratumoral administration of dendritic cells is a potent strategy for the treatment of melanoma.
Lee
J-R
JR
Department of Dermatology, Gil Medical Center, Gachon University, and Clinical Research Centre, Inha University Hospital, Incheon, South Korea.
Shin
J-H
JH
Park
J-H
JH
Song
S-U
SU
Choi
G-S
GS
D000287:Administration, Topical; D000634:Aminoquinolines / Q000008:administration & dosage*; D000818:Animals; D000970:Antineoplastic Agents / Q000008:administration & dosage*; D003131:Combined Modality Therapy / Q000379:methods; D003713:Dendritic Cells / Q000637:transplantation*; D005260:Female; D000077271:Imiquimod; D016219:Immunotherapy, Adoptive / Q000379:methods*; D015552:Injections, Intralesional / Q000379:methods; D008545:Melanoma / Q000628:therapy*; D051379:Mice; D008810:Mice, Inbred C57BL; D009368:Neoplasm Transplantation / Q000379:methods; D012878:Skin Neoplasms / Q000628:therapy*
D000634:Aminoquinolines; D000970:Antineoplastic Agents; D000077271:Imiquimod