ABSTRACT: Gene Expression Profiling of human monocytes: Combination Therapy with Anti–CTLA-4 and Anti–PD-1 Leads to Distinct Immunologic Changes In Vivo
Project description:Transcriptome analysis of human peripheral blood monocytes Combination therapy concurrently targeting PD-1 and CTLA-4 immune checkpoints leads to remarkable antitumor effects. Although both PD-1 and CTLA-4 dampen the T cell activation, the in vivo effects of these drugs in humans remain to be clearly defined. To better understand biologic effects of therapy, we analyzed blood/tumor tissue from patients undergoing single or combination immune checkpoint blockade. We show that blockade of CTLA-4, PD-1, or combination of the two leads to distinct genomic (changes in gene-expression profile) and functional signatures in vivo in purified human T cells and monocytes. RNA extracted from freshly isolated monocytes from peripheral blood of patients treated with either antiâPD-1 (n = 6), antiâCTLA-4 (n = 5), Combo therapy with antiâPD-1 and antiâCTLA-4 concurrently (Combo, n = 6), and Seq antiâPD-1 in patients with prior antiâCTLA-4 (Seq, n = 3) was analyzed using the Affymetrix GeneChip Human Transcriptome 2.0 exon array. No techinical replicates were performed.
Project description:Transcriptome analysis of human peripheral blood monocytes Combination therapy concurrently targeting PD-1 and CTLA-4 immune checkpoints leads to remarkable antitumor effects. Although both PD-1 and CTLA-4 dampen the T cell activation, the in vivo effects of these drugs in humans remain to be clearly defined. To better understand biologic effects of therapy, we analyzed blood/tumor tissue from patients undergoing single or combination immune checkpoint blockade. We show that blockade of CTLA-4, PD-1, or combination of the two leads to distinct genomic (changes in gene-expression profile) and functional signatures in vivo in purified human T cells and monocytes.
Project description:Transcriptome analysis of human peripheral blood T cells Combination therapy concurrently targeting PD-1 and CTLA-4 immune checkpoints leads to remarkable antitumor effects. Although both PD-1 and CTLA-4 dampen the T cell activation, the in vivo effects of these drugs in humans remain to be clearly defined. To better understand biologic effects of therapy, we analyzed blood/tumor tissue from patients undergoing single or combination immune checkpoint blockade. We show that blockade of CTLA-4, PD-1, or combination of the two leads to distinct genomic (changes in gene-expression profile) andfunctional signatures in vivo in purified human T cells. RNA extracted from freshly isolated T cells from peripheral blood of patients treated with either antiâ??PD-1 (n = 6), antiâ??CTLA-4 (n = 5), Combo therapy with antiâ??PD-1 and antiâ??CTLA-4 concurrently (Combo, n = 6), and Seq antiâ??PD-1 in patients with prior antiâ??CTLA-4 (Seq, n = 3) was analyzed using the Affymetrix GeneChip Human Transcriptome 2.0 exon array. No techinical replicates were performed.
Project description:Transcriptome analysis of human peripheral blood T cells Combination therapy concurrently targeting PD-1 and CTLA-4 immune checkpoints leads to remarkable antitumor effects. Although both PD-1 and CTLA-4 dampen the T cell activation, the in vivo effects of these drugs in humans remain to be clearly defined. To better understand biologic effects of therapy, we analyzed blood/tumor tissue from patients undergoing single or combination immune checkpoint blockade. We show that blockade of CTLA-4, PD-1, or combination of the two leads to distinct genomic (changes in gene-expression profile) andfunctional signatures in vivo in purified human T cells.
Project description:Gene Expression Profiling of human T cells: Combination Therapy with Anti–CTLA-4 and Anti–PD-1 Leads to Distinct Immunologic Changes In Vivo
Project description:Although high clinical response rates are seen for immune checkpoint blockade (ICB) of metastatic melanoma, both intrinsic and acquired ICB resistance remain formidable challenges. Combination ICB shows improved clinical benefit, but is associated with severe adverse events and exceedingly high cost. Therefore, there is a dire need to stratify individual patients for their likelihood of responding to either anti-PD-1 or anti-CTLA-4 monotherapy, or the combination. Since it is conceivable that ICB responses are influenced by both tumor cell-intrinsic and stromal factors, we hypothesized that a predictive classifier ought to mirror both of these distinct features. We used a panel of melanoma patient-derived xenografts (PDX), in which human stromal cells upon transplantation are naturally replaced by their murine counterparts, to computationally subtract PDX RNA expression signals from those in patients’ melanomas. We thus derived both “Stromal immune” (SIM) and tumor cell-specific “Tumor-autonomous inflammation” (TAF) signatures. Here we report that the SIM signature predicts response to anti-CTLA-4 but not anti-PD-1 treatment, whereas the tumor TAF signature predicts response to anti-PD-1 but not anti-CTLA-4. Moreover, when used in conjunction, the signatures accurately predict response in two independent patient cohorts treated with the anti-CTLA-4 + anti-PD-1 combination. These signatures may be clinically exploited for personalized treatment advice based on the predicted benefit from either anti-CTLA-4 or anti-PD-1 monotherapy or their combination.
Project description:Intracranial B16 melanoma tumors isolated from C57Bl6 mice were analyzed by mRNAseq. Four experimental groups were analyzed: (1) Mice with intracranial tumors receiving IgG; (2) Mice with intracranial tumors receiving anti-PD-1 plus anti-CTLA-4 therapy; (3) Mice with intracranial plus extracranial tumors receiving IgG; (4) Mice with intracranial plus extracranial tumors receiving anti-PD-1 plus anti-CTLA-4 therapy. Taggart et al., PNAS 2018;
Project description:We used single cell (sc) RNA-seq to analyze responding SM1 melanoma flank tumors and SM1 brain metastases to explore the mechanism of action of the anti-PD-1+LAG-3 and the anti-PD-1+CTLA-4 combination.
Project description:The ability to modulate immune-inhibitory pathways using checkpoint blockade antibodies such as PD-1, PD-L1, and CTLA-4 represents a significant breakthrough in cancer therapy in recent years. This has driven interest in identifying small-molecule-immunotherapy combinations to increase the proportion of responses. Murine syngeneic models, which have a functional immune system, represent an essential tool for pre-clinical evaluation of new immunotherapies. However, immune response varies widely between models and the translational relevance of each model is not fully understood, making selection of an appropriate pre-clinical model for drug target validation challenging. Utilizing RNAseq transcriptomic profiling, we have characterised the changes in gene regulatory pathways and immune populations in CT26 mice after treatment with the combination of anti-PD-L1 and anti-CTLA-4 antibodies. At day 7 post tumor implant, the pathways analysis of differentially expressed genes indicated an enrichment for migration of leukocytes in response to inflammation and communication between innate and adaptive immune cells. Similarly, analysis of upstream regulators suggested that lipopolysaccharide, IL-1B, TNF, IFNG, and NFKB1A pathways associated with inflammation were activated. At day 14, pathways related T-helper cell signalling pathways were upregulated. In addition, upstream regulators of the lipopolysaccharide and IFNG pathway, as well STAT1 and IL21 pathway were enriched, indicative of innate and adaptive immune response to inflammation.
Project description:Immune checkpoint inhibitors (CPIs) have revolutionised cancer treatment, with previously untreatable disease now amenable to potential cure. Combination regimens of anti-CTLA-4 and anti-PD-1 show enhanced efficacy but are prone to off-target immune-mediated tissue injury, particularly at the barrier surfaces. CPI-induced colitis is a common and serious complication. A higher proportion of patients undergoing monotherapy anti-CTLA-4 treatment tend to develop colitis compared to monotherapy treated anti-PD-1 treated patients. This effect is enhanced when patients are treated with both drugs. To probe the impact of either anti-CTLA4 or anti-PD1 on intestinal homeostasis, mice were challenged with anti-CTLA-4 and anti-PD-1 immunotherapy in either monotherapy or together in combination. Manipulation of the intestinal microbiota has also been shown to be important in both this model, from previous data, and in patients. Colonic immune responses were then profiled using bulk RNA-sequencing.