CD40ligand-expressing dendritic cells induce regression of hepatocellular carcinoma by activating innate and acquired immunity in vivo.
Dendritic cells (DCs) are professional antigen-presenting cells able to prime T-cells against tumor-associated antigens (TAA), but their potential to induce hepatocellular carcinoma (HCC) regression is still limited. CD40/CD40L interaction is essential for DC activation and induction of antigen-specific T-cells. In this study, transduction of TAA-pulsed DC with a CD40L-encoding adenovirus (Ad-CD40L) was used to improve the immune response induced by DC toward HCC. Bone marrow-derived DC from C3H/HeNcrl mice were cultured with granulocyte-macrophage colony-stimulating factor and interleukin-4. On day 6, tumor-lysate pulsed DCs were infected with adenoviruses. HCCs were induced by inoculation of mice with Hepa129-cells subcutaneously. When tumor-volume was 100 to 400 mm(3), DCs were injected intratumorally, subcutaneously, or intravenously. Ad-CD40L transduction exerted CD40/CD40L interactions between DCs, increasing DC immunostimulation with up-regulation of CD80/CD86- and interleukin-12 (IL-12) expression. Intratumoral injection of CD40L-DC was superior to intravenous or subcutaneous treatments, yielding tumor elimination in almost 70% of mice. Moreover, all tumor-free animals were protected against hepatic tumor cell rechallenge. In a preventive setting, subcutaneous injection of CD40L-expressing DCs protected 50% of mice for more than 3 months toward tumor cell challenge. The induced immune response seemed to be dependent on cross-priming with Th1-lymphocytes in the lymph nodes, because transduced DCs were redetected in lymphoid tissues. In addition, immunohistochemistry of tumors indicated a significant tumor infiltration with CD4+, CD8+ T cells and natural killer (NK) cells. Tumor-infiltrating lymphocytes were tumor-specific, as shown in interferon-gamma (IFN-gamma) enzyme-linked immunosorbent spot and T-cell proliferation assays.


CONCLUSIONS
Transduction of DCs with Ad-CD40L increases significantly the stimulatory capacity of DCs. Intratumoral injection of DCs activates both acquired and innate immunity, inducing complete regression of established tumors and long-term immunity against tumor recurrence. This approach improves the antitumoral potential of DCs.
Department of Internal Medicine I, University of Bonn, Bonn, Germany.
Maria A
MA
Gonzalez-Carmona
Veronika
V
Lukacs-Kornek
Anne
A
Timmerman
Sara
S
Shabani
Miroslaw
M
Kornek
Annabelle
A
Vogt
Yildiz
Y
Yildiz
Elisabeth
E
Sievers
Ingo G H
IG
Schmidt-Wolf
Wolfgang H
WH
Caselmann
Tilman
T
Sauerbruch
Volker
V
Schmitz
D000818:Animals; D023201:CD40 Ligand / Q000378:metabolism*; D006528:Carcinoma, Hepatocellular / Q000276:immunology* / Q000473:pathology / Q000601:surgery; D045744:Cell Line, Tumor; D018920:Coculture Techniques; D003602:Cytotoxicity, Immunologic; D003713:Dendritic Cells / Q000276:immunology* / Q000378:metabolism / Q000637:transplantation*; D018450:Disease Progression; D007110:Immunity, Active; D007113:Immunity, Innate; D015552:Injections, Intralesional; D018664:Interleukin-12 / Q000097:blood / Q000378:metabolism; D008114:Liver Neoplasms, Experimental / Q000276:immunology* / Q000473:pathology / Q000601:surgery; D008214:Lymphocytes / Q000276:immunology; D008297:Male; D051379:Mice; D008809:Mice, Inbred C3H; D009364:Neoplasm Recurrence, Local / Q000517:prevention & control; D010641:Phenotype; D013154:Spleen / Q000166:cytology; D014161:Transduction, Genetic; D014611:Vaccination
D023201:CD40 Ligand; D018664:Interleukin-12