Project description:Adoptive transfer of genetically or nanoparticle-engineered macrophages represents a promising cell therapy modality for treatment of solid tumor. However, the therapeutic efficacy is suboptimal without achieving a complete tumor regression, and the underlying mechanism remains elusive. Here, we discover a subpopulation of cancer cells with upregulated CD133 and programmed death-ligand 1 in mouse melanoma, resistant to the phagocytosis by the transferred macrophages. Compared to the CD133-PD-L1- cancer cells, the CD133+PD-L1+ cancer cells express higher transforming growth factor-β signaling molecules to foster a resistant tumor niche, that restricts the trafficking of the transferred macrophages by stiffened extracellular matrix, and inhibits their cell-killing capability by immunosuppressive factors. The CD133+PD-L1+ cancer cells exhibit tumorigenic potential. The CD133+PD-L1+ cells are further identified in the clinically metastatic melanoma. Hyperthermia reverses the resistance of CD133+PD-L1+ cancer cells through upregulating the ‘eat me’ signal calreticulin, significantly improving the efficacy of adoptive macrophage therapy. Our findings demonstrate the mechanism of resistance to adoptive macrophage therapy, and provide a de novo strategy to counteract the resistance.
Project description:Adoptive transfer of genetically or nanoparticle-engineered macrophages represents a promising cell therapy modality for treatment of solid tumor. However, the therapeutic efficacy is suboptimal without achieving a complete tumor regression, and the underlying mechanism remains elusive. Here, we discover a subpopulation of cancer cells with upregulated CD133 and programmed death-ligand 1 in mouse melanoma, resistant to the phagocytosis by the transferred macrophages. Compared to the CD133-PD-L1- cancer cells, the CD133+PD-L1+ cancer cells express higher transforming growth factor-β signaling molecules to foster a resistant tumor niche, that restricts the trafficking of the transferred macrophages by stiffened extracellular matrix, and inhibits their cell-killing capability by immunosuppressive factors. The CD133+PD-L1+ cancer cells exhibit tumorigenic potential. The CD133+PD-L1+ cells are further identified in the clinically metastatic melanoma. Hyperthermia reverses the resistance of CD133+PD-L1+ cancer cells through upregulating the ‘eat me’ signal calreticulin, significantly improving the efficacy of adoptive macrophage therapy. Our findings demonstrate the mechanism of resistance to adoptive macrophage therapy, and provide a de novo strategy to counteract the resistance.
Project description:Adoptive transfer of genetically or nanoparticle-engineered macrophages represents a promising cell therapy modality for treatment of solid tumor. However, the therapeutic efficacy is suboptimal without achieving a complete tumor regression, and the underlying mechanism remains elusive. Here, we discover a subpopulation of cancer cells with upregulated CD133 and programmed death-ligand 1 in mouse melanoma, resistant to the phagocytosis by the transferred macrophages. Compared to the CD133-PD-L1- cancer cells, the CD133+PD-L1+ cancer cells express higher transforming growth factor-β signaling molecules to foster a resistant tumor niche, that restricts the trafficking of the transferred macrophages by stiffened extracellular matrix, and inhibits their cell-killing capability by immunosuppressive factors. The CD133+PD-L1+ cancer cells exhibit tumorigenic potential. The CD133+PD-L1+ cells are further identified in the clinically metastatic melanoma. Hyperthermia reverses the resistance of CD133+PD-L1+ cancer cells through upregulating the 'eat me' signal calreticulin, significantly improving the efficacy of adoptive macrophage therapy. Our findings demonstrate the mechanism of resistance to adoptive macrophage therapy, and provide a de novo strategy to counteract the resistance.
Project description:Adoptive T-cell therapy or oncolytic virotherapy has made significant progress, but the efficacy was limited by the lack of infiltration into solid tumors when used alone. Here, an oncolytic virus (rVSV-LCMVG) was designed and combined with adoptively transferred T cells. By turning cold tumors hot, in B16 tumor-bearing mice, combination therapy showed superior antitumor effects than monotherapy, whether rVSV-LCMVG was administered intratumorally or intravenously. Combination therapy significantly increased cytokine and chemokine levels within tumors and sensitized refractory tumors by boosting T-cell recruitment, down-regulating the expression of PD1, and restoring effector-T cell function. To offer a combination therapy with greater translational value, mRNA vaccines were introduced to induce tumor-specific T cells instead of adoptively transferred T cells, and exhibited comparable amplified anti-tumor effects. This study proposed a rational combination therapy of oncolytic virus with adoptive T-cell transfer or mRNA vaccines encoding tumor-associated antigens, in terms of synergistic efficacy and mechanism.
Project description:Adoptive T-cell therapy or oncolytic virotherapy has made significant progress, but the efficacy was limited by the lack of infiltration into solid tumors when used alone. Here, an oncolytic virus (rVSV-LCMVG) was designed and combined with adoptively transferred T cells. By turning cold tumors hot, in B16 tumor-bearing mice, combination therapy showed superior antitumor effects than monotherapy, whether rVSV-LCMVG was administered intratumorally or intravenously. Combination therapy significantly increased cytokine and chemokine levels within tumors and sensitized refractory tumors by boosting T-cell recruitment, down-regulating the expression of PD1, and restoring effector-T cell function. To offer a combination therapy with greater translational value, mRNA vaccines were introduced to induce tumor-specific T cells instead of adoptively transferred T cells, and exhibited comparable amplified anti-tumor effects. This study proposed a rational combination therapy of oncolytic virus with adoptive T-cell transfer or mRNA vaccines encoding tumor-associated antigens, in terms of synergistic efficacy and mechanism.
Project description:Here we report a new way to reverse the tolerant state of adoptively transferred CD8+ T cells against melanoma through ex vivo expansion with the TLR9 agonist CpG. CpG-generated T cells elicited potent immunity without co-administration of high dose IL-2 or vaccination, which are adjuvants classically required to effectively treat solid tumors. CpG-expanded T cells exhibited an IL-2RhighICOShighCD39low phenotype ex vivo and engrafted robustly in vivo. In culture, B cells were the only cell type essential for imprinting T cells with this phenotype and potent tumor immunity. CpG agonists targeting B cells, but not dendritic cells, generated CD8+ T cell products with remarkable antitumor properties. Purified B cells were sufficient to mediate the CpG-associated changes in T cells. These findings reveal a vital role for B cells in the generation of effective antitumor T cells and have immediate implications for profoundly improving immunotherapy for patients.
Project description:To gain insight into the transcriptional program conferred to Th cells by B cells, we conducted microarray gene expression analyses of adoptively transferred OT-II cells sorted from the mesenteric lymph nodes of bone marrow chimeric control and MHCIIB-/- mice 5 days after immunization with OVA and polyI:C.