Cryo-thermal therapy induces macrophage polarization for durable anti-tumor immunity

Abstract

Many cancer therapies are being developed for the induction of durable anti-tumor immunity, especially for malignant tumors. The activation of antigen-presenting cells (APCs), including macrophages and dendritic cells (DCs), can bridge innate and adaptive immune responses against tumors. However, APCs have an immunosuppressive phenotype and reversing it for effective tumor-specific antigen presenting is critical in developing new cancer treatment strategies. We previously developed a novel cryo-thermal therapy to treat malignant melanoma in a mouse model; long-term survival and durable anti-tumor immunity were achieved, but the mechanism involved was unclear. This study revealed cryo-thermal therapy-induced macrophage polarization to the M1 phenotype and modulated the phenotypic and functional maturation of DCs with high expression of co-stimulatory molecules, increased pro-inflammatory cytokine production, and downregulated immuno-inhibitory molecule expression. Further, we observed CD4 + T-cell differentiation into Th1 and cytotoxic T-cell sub-lineages and generation of cytotoxic CD8 + T cells, in which M1 macrophage polarization had a direct, important role. The results indicated that cryo-thermal-induced macrophage polarization to the M1 phenotype was essential to mediate durable anti-tumor immunity, leading to long-term survival. Thus, cryo-thermal therapy is a promising strategy to reshape host immunosuppression, trigger persistent memory immunity for tumor eradication, and inhibit metastasis in the long term.

Neoantigen-specific CD4+T-cell response is critical for the therapeutic efficacy of cryo-thermal therapy

“…29 Our previous studies demonstrated that the percentage of CD4 + and CD8 + T-cells was significantly increased after cryo-thermal therapy. [17][18][19] However, whether tumor antigen-specific CD4 + and CD8 + T-cells were induced by cryo-thermal therapy had not been addressed. MHC-Irestricted peptides of TRP2, tyrosinase and gp100, three known antigens of B16F10 melanoma 21 were used to estimate the frequency of antigen-specific CD8 + T-cells, and MHC-II-restricted peptides of B16-M30 and B16-M20, two neoantigens of B16F10 melanoma 21 were used to estimate the frequency of antigen-specific CD4 + T-cells.…”

Hyperthermia Targeting the Tumor Microenvironment Facilitates Immune Checkpoint Inhibitors

“…In addition, hyperthermia can also inhibit tolerogenic “eat me” signals by transforming immature APCs and/or APCs exhibiting immunosuppressive phenotypes (M2 macrophages, N2 neutrophils, myeloid-derived suppressor cells) to a relatively mature one ( 54 , 55 ). This transformations include infiltrating activated monocytes into the tumor microenvironment ( 56 ), inducing immature DCs to differentiate into DCs ( 45 ), promoting macrophage polarization to the M1 type that exerts pro-inflammatory effects, and promoting the release of inflammatory factors ( 57 , 58 ). In fact, significantly increased phagocytosis rates of macrophages and DCs have been seen; moreover, this process seems to be temperature sensitive (>43°C).…”

Iron Released after Cryo-Thermal Therapy Induced M1 Macrophage Polarization, Promoting the Differentiation of CD4+ T Cells into CTLs

“…Our previous studies showed that cryo-thermal therapy modulates the phenoty and functional maturation of splenic DCs [16,44]. Based on these results, the markers mature CD11c + DCs were determined by using flow cytometry (Figure S1) and RT-qPC At 24 h after cryo-thermal therapy, the percentage of CD86 + MHC Ⅱ + DCs in the sple was not obviously different after 24 h but was increased after 72 h compared to the cont…”

“…Our previous studies showed that cryo-thermal therapy modulates the phenotypic and functional maturation of splenic DCs [16,44]. Based on these results, the markers of mature CD11c + DCs were determined by using flow cytometry (Figure S1) and RT-qPCR.…”

“…In our previous study, we developed a cryo-thermal therapy technique that leads to complete regression of implanted tumors and extends long-term survival [8][9][10][11][12][13][14]. Cryo-2 of 19 thermal therapy has been shown to induce M1 macrophage polarization, leading to longlasting, CD4 + T cell-mediated, Th1-dominant antitumor immunity [9,15,16]. HSP70 released after cryo-thermal therapy can promote M1 macrophage polarization [17].…”