OX40 ligand expressed by DCs costimulates NKT and CD4⁺ Th cell antitumor immunity in mice
J. Clin. Invest. Jamal Zaini, et al. 117:3330 doi:10.1172/JCI32693 [Go to this article.]

Figure 3
Involvement of NKT cells in the therapeutic effect elicited by intratumoral administration of AdOX40L-modified DCs. (A) Immunohistochemical evaluation of tumors for OX40⁺ cells. Three days after injection of AdOX40L- or AdNull-modified DCs to B16-F10 tumors, frozen sections of the tumors were stained with anti-mouse OX40 antibody. Numbers at bottom right denote the number of positive cells per 10 random high-power fields (original magnification, ×400). Untreated tumors were used as controls. (B) OX40⁺CD1d/α-GalCer dimer⁺ cells. OX40⁺ cells from tumors treated with AdOX40L-modified DCs were analyzed for the CD1d/α-GalCer dimer binding by flow cytometry. Overlay (filled) histogram depicts OX40⁺ cells stained without dimer. The percentage of CD1d/α-GalCer dimer⁺ cells above control staining is shown. (C) Quantification of intratumoral NKT cells. The number of CD1d/α-GalCer dimer⁺ NKT cells in tumors treated as in A was determined by flow cytometry. (D and E) Role of NKT cells. NKT cell^–/– (circles) or wild-type mice (triangles) bearing B16-F10 tumors were treated with AdOX40L-modified DCs. Tumor-bearing wild-type mice without any treatment (squares) were used as controls. (F and G) Role of OX40 on NKT cells. The NKT cell^–/– mice were reconstituted with OX40^–/– (circles) or wild-type NKT cells (triangles) 1 day before the treatment. (H and I) Role of CD1d on DCs. CD1d^–/– (circles) or wild-type DCs (triangles) were used to prepare AdOX40L-modified DCs for the treatment. (D, F, and H) The size of each tumor was assessed to evaluate tumor growth. (E, G, and I) At 10 days after treatment, splenocytes were isolated and assayed for cytolytic function using B16-F10 or LLC cells as target cells.