AMPK activator AICAR in combination with anti-mouse IL10 mAb restores the functionality of intra-tumoral Tfh cells in the 4T1 mouse model

[Display omitted] •CD4+Foxp3+CXCR5+PD1+ Tfr cells and PD-L1+ cells upregulate in the systemic circulation of 4T1 tumor-bearing mouse.•Anti-IL10 mAb potently improves Tfh cell frequency and suppressed Tfr cell proliferation in 4T1 mouse.•The addition of 2DG and Etomoxir reduced tumor growth but could not improve Tfh cell response to a high extent; synergistic treatment of 2DG/Etomoxir + anti-IL10 mAb alleviates Tfh cells, memory B, and GC B cells in 4T1 mouse.•AMPK activator AICAR along with anti-IL10 mAb ameliorated anti-tumor immunity by elevating Tfh cells, memory B, GC B, and plasmablasts in tumor-draining, axillary, and mesenteric LNs. 4T1 cell-mediated TNBC breast cell carcinoma is a highly malignant mice tumor model which resembles an advanced stage of breast cancer in humans. Tumor progression occurs depending on the intra-tumoral balance of pro- and anti- tumorigenic immune cells. Enhancement of T-cell-mediated anti-tumor immunity will be advantageous for inhibiting tumor progression and improving the efficacy of cancer therapy. This study is focused on alleviating suppressed anti-tumor immune response by improving CD4+ T follicular helper cell (Tfh) response in 4T1 mice. We employed anti-IL10 mAb along with metabolic drugs 2-deoxy-D-glucose (2DG) which inhibits the glycolytic pathway and Cpt1a inhibitor Etomoxir which inhibits FAO. AMPK activator AICAR with or without anti-IL10 mAb was also used to ameliorate metabolic stress and exhaustion faced by immune cells. Our results demonstrate that synergistic treatment with 2DG/Etomoxir + anti-IL10 mAb induced Tfh cell, memory B, and GC B cell response more potently compared to treatment with 2DG or Etomoxir treatment alone as observed in several LNs and tumor tissue of 4T1 mouse. However, AICAR + anti-IL10 mAb increased the frequency of intratumoral Tfh cells, simultaneously downregulated Tfr cells; and improved humoral response by stimulating upregulation of memory B, GC B, and plasmablasts in tumor-draining, axillary, and mesenteric LNs of 4T1 mouse.