Journal:
Article Title: Immune Stimulatory Receptor CD40 Is Required for T-Cell Suppression and T Regulatory Cell Activation Mediated by Myeloid-Derived Suppressor Cells in Cancer
doi: 10.1158/0008-5472.CAN-09-1882
Figure Lengend Snippet: CD40 is essential for Treg expansion, immune suppression, and tumor promotion mediated by MDSCs. OVA-B16–bearing MaFIA mice (CD45.2) were left untreated or depleted of CD115+ cells followed by adoptive transfer of CD45.1 OT-II T cells and reconstitution of WT or CD40 KO MDSC. A, tumor (OVA)–specific CD4+CD25+Foxp3+ Tregs in the tumor. Tumor infiltrated leukocytes were isolated and stained with antibodies against CD45.1, CD4, CD25, and Foxp3 or isotype controls followed by flow cytometry. Contour plots gated on CD45.1+CD4+ population are presented. One of three reproducible experiments (n = 3–4 per group) was presented. B, the number of tumor (OVA)–specific Tregs in the tumor. The numbers of CD45.1+ OT-II Tregs in the tumor were calculated (second versus first column, P < 0.001; fourth versus third column, P = 0.004). C, proliferative response of tumor (OT-II)–specific T cells reisolated from the recipient MaFIA mice. CD45.1+ OT-II T cells were reisolated from the spleen of recipient mice and stimulated with OVA peptide (1 μg/mL) in the presence of irradiated naïve splenocytes for 3 d. [3H]Thymidine was added in the last 8 h of culture (second versus first column, P = 0.002; fourth versus third column, P = 0.009). D, tumor weight in various treatment groups. Tumors were resected from tumor-bearing mice and weighed (second versus first column, P = 0.011; fourth versus third column, P = 0.006). Data were combined from three reproducible experiments (n = 9).
Article Snippet: Wild-type (WT) BALB/c, CD40-deficient BALB/c, ovalbumin (OVA)–specific MHC class II–restricted TCR-transgenic (OT-II) CD45.1 C57BL6, and CD40 knockout (KO) CD45.2 C57BL6 mice were purchased from National Cancer Institute and The Jackson Laboratory.
Techniques: Adoptive Transfer Assay, Isolation, Staining, Flow Cytometry, Irradiation