Similar Datasets
Project description:The adult heart responds to injury by scarring with consequent loss of contractile function, whereas the neonatal heart possesses the ability to regenerate. We compared the immune response to injury in neonatal and adult mouse hearts and discovered that the PD1/PD-L1 immune checkpoint pathway is highly activated in regenerative hearts but is silenced in later life. Deletion of the PD1 receptor or inactivation of its PD-L1 ligand prevented regeneration of neonatal hearts after injury. Our findings reveal a previously unrecognized role of the PD1/PD-L1 pathway in the control of heart regeneration through modulating T cell activity and inflammation following injury and provide new inroads into the control of adult tissue regeneration.
2023-06-01 | GSE207215 | GEO
Project description:The adult heart responds to injury by scarring with consequent loss of contractile function, whereas the neonatal heart possesses the ability to regenerate. We compared the immune response to injury in neonatal and adult mouse hearts and discovered that the PD1/PD-L1 immune checkpoint pathway is highly activated in regenerative hearts but is silenced in later life. Deletion of the PD1 receptor or inactivation of its PD-L1 ligand prevented regeneration of neonatal hearts after injury. Our findings reveal a previously unrecognized role of the PD1/PD-L1 pathway in the control of heart regeneration through modulating T cell activity and inflammation following injury and provide new inroads into the control of adult tissue regeneration.
2023-06-01 | GSE207289 | GEO
Project description:The PD-1/PD-L1 pathway maintains an immunosuppressive environment essential for neonatal heart regeneration
| PRJNA854636 | ENA
Project description:The PD-1/PD-L1 pathway maintains an immunosuppressive environment essential for neonatal heart regeneration [Spatial]
| PRJNA854163 | ENA
Project description:The PD-1/PD-L1 pathway maintains an immunosuppressive environment essential for neonatal heart regeneration [scRNA-seq]
| PRJNA854641 | ENA
Project description:Global proteomics data captured from P8 hearts, 7 days post-MI or sham surgery. Hearts were treated at 4, 5, and 6 days post surgery with saline or rapamycin.
2023-07-13 | MSV000092436 | MassIVE
Project description:Programmed death-ligand 1 (PD-L1) expression on tumor cells is essential for T cell impairment, and PD-L1 blockade therapy has shown unprecedented durable responses in several clinical studies. Although higher expression of PD-L1 on tumor cells is associated with a better immune response after Ab blockade, some PD-L1-negative patients also respond to this therapy. In the current study, we explored whether PD-L1 on tumor or host cells was essential for anti-PD-L1-mediated therapy in 2 different murine tumor models. Using real-time imaging in whole tumor tissues, we found that anti-PD-L1 Ab accumulates in tumor tissues, regardless of the status of PD-L1 expression on tumor cells. We further observed that, while PD-L1 on tumor cells was largely dispensable for the response to checkpoint blockade, PD-L1 in host myeloid cells was essential for this response. Additionally, PD-L1 signaling in defined antigen-presenting cells (APCs) negatively regulated and inhibited T cell activation. PD-L1 blockade inside tumors was not sufficient to mediate regression, as limiting T cell trafficking reduced the efficacy of the blockade. Together, these findings demonstrate that PD-L1 expressed in APCs, rather than on tumor cells, plays an essential role in checkpoint blockade therapy, providing an insight into the mechanisms of this therapy.
| S-EPMC5785245 | biostudies-literature
Project description:Tumor cells subvert immune surveillance by harnessing signals from immune checkpoints to acquire immune resistance. The protein PD-L1 is an important component in this process, and inhibition of PD-L1 elicits durable anti-tumor responses in a broad spectrum of cancers. However, immune checkpoint inhibition that target known pathways is not universally effective. A better understanding of the genetic repertoire underlying these processes is necessary to expand our knowledge in tumor immunity and to facilitate identification of alternative targets. Here, we present a CRISPR/Cas9 screen in human cancer cells to identify genes that confer tumors with the ability to evade the cytotoxic effects of the immune system. We show that the transcriptional regulator MLLT6 (AF17) is required for efficient PD-L1 protein expression and cell surface presentation in cancer cells. MLLT6 depletion alleviates suppression of CD8+ cytotoxic T cell-mediated cytolysis. Furthermore, cancer cells lacking MLLT6 exhibit impaired STAT1 signaling and are insensitive to interferon-γ-induced stimulation of IDO1, GBP5, CD74, and MHC class II genes. Collectively, our findings establish MLLT6 as a regulator of oncogenic and interferon-γ-associated immune resistance.
| S-EPMC7726806 | biostudies-literature
Project description:The neonatal heart can efficiently regenerate within a short period after birth, whereas the adult mammalian heart has extremely limited capacity to regenerate. The molecular mechanisms underlying neonatal heart regeneration remain elusive. Here, we revealed that as a coreceptor of Wnt signalling, low-density lipoprotein receptor-related protein 5 (LRP5) is required for neonatal heart regeneration by regulating cardiomyocyte proliferation. The expression of LRP5 in the mouse heart gradually decreased after birth, consistent with the time window during which cardiomyocytes withdrew from the cell cycle. LRP5 downregulation reduced the proliferation of neonatal cardiomyocytes, while LRP5 overexpression promoted cardiomyocyte proliferation. The cardiac-specific deletion of Lrp5 disrupted myocardial regeneration after injury, exhibiting extensive fibrotic scars and cardiac dysfunction. Mechanistically, the decreased heart regeneration ability induced by LRP5 deficiency was mainly due to reduced cardiomyocyte proliferation. Further study identified AKT/P21 signalling as the key pathway accounting for the regulation of cardiomyocyte proliferation mediated by LRP5. LRP5 downregulation accelerated the degradation of AKT, leading to increased expression of the cyclin-dependent kinase inhibitor P21. Our study revealed that LRP5 is necessary for cardiomyocyte proliferation and neonatal heart regeneration, providing a potential strategy to repair myocardial injury.
| S-EPMC9097834 | biostudies-literature
Project description:Programmed cell death 1 (PD-1) is an immuno-checkpoint receptor which is primarily expressed on T cells, monocytes, natural killer cells and macrophages. Programmed death-ligand 1 (PD-L1) is the primary ligand of PD-1 and is constitutively expressed on antigen presenting cells, mesenchymal stem cells and bone marrow-derived mast cells. In addition, PD-L1 is also expressed on a wide range of tumor cells, including lung cancer, breast cancer and melanoma. PD-1 and PD-L1 are important members of the immunoglobulin super-family and participate in immune regulation. In the present study, the immune-suppressive effects of a number of tumor cell lines were determined. The breast tumor cell lines MCF-7 and MDA-MB-231 displayed the largest inhibitory effects on T-cell activation and cytokine secretion in a co-culture system. The HepG2, A549 and A375 cells displayed limited inhibitory effects. MCF-7 and MDA-MB-231 cells expressed the highest level of PD-L1 among the cells used, which may explain their higher immuno-suppressive effects. Compound A0-L, a small molecule inhibitor of the PD-1/PD-L1 interaction, restored T cell functions. Additionally, it was demonstrated that the tumor cells with higher levels of PD-L1 expression suppressed signaling pathways involved in T-cell activation, such as the T-cell receptor- zeta chain of T cell receptor associated protein kinase ZAP70-RAS-GTPase-extracellular-signal-regulated kinases and CD28-PI3K-Akt serine/threonine kinases pathways. These findings suggest that tumor cells with higher expression levels of PD-L1 may exhibit higher immuno-suppressive activity, and that drugs targeting the PD-1/PD-L1 interaction may have improved therapeutic effects on tumors expressing higher levels of PD-L1.
| S-EPMC6781757 | biostudies-literature