Project description:TurboID (biotin proximity ligase) was fused to AML-associated oncofusions (PML::RARA, RUNX1::RUNX1T1, CBFB::MYH11), wildtype NPM1, or mutated NPMc and expressed in murine hematopoietic stem/progenitor cells using MSCV-based retroviruses to identify key interacting proteins in primary hematopoietic cells.
Project description:This is a mathematical model describing the hematopoietic lineages with leukemia lineages, as controlled by end-product negative feedback inhibition. Variables include hematopoietic stem cells, progenitor cells, terminally differentiated HSCs, leukemia stem cells, and terminally differentiated leukemia stem cells.
Project description:A greater understanding of hematopoietic stem cell (HSC) regulation is required for dissecting protective versus detrimental immunity to pathogens that cause chronic infections such as Mycobacterium tuberculosis (Mtb). We have shown that systemic administration of BCG or b-glucan reprograms HSCs in the BM via a type II interferon (IFN-II) or IL1 response, respectively, that confers protective trained immunity against Mtb. Yet, whether BCG/β-Glucan is unique in its ability to induce this protection remains unknown. Herein, we demonstrate that unlike BCG or b-glucan, Mtb reprograms HSCs via IFN-I response that suppresses myelopoiesis and impairs protective trained immunity to Mtb. Mechanistically, IFN-I response dysregulates iron metabolism, depolarizes mitochondrial membrane potential, and induces cell death in myeloid progenitors. Finally, activation of IFN-I/iron axis in myeloid progenitors generates a detrimental trained immunity to Mtb infection. These results identify an unanticipated immune evasion strategy of Mtb in the bone marrow that controls the magnitude and anti-microbial capacity of innate immunity to infection
Project description:A greater understanding of hematopoietic stem cell (HSC) regulation is required for dissecting protective versus detrimental immunity to pathogens that cause chronic infections such as Mycobacterium tuberculosis (Mtb). We have shown that systemic administration of BCG or b-glucan reprograms HSCs in the BM via a type II interferon (IFN-II) or IL1 response, respectively, that confers protective trained immunity against Mtb. Yet, whether BCG/β-Glucan is unique in its ability to induce this protection remains unknown. Herein, we demonstrate that unlike BCG or b-glucan, Mtb reprograms HSCs via IFN-I response that suppresses myelopoiesis and impairs protective trained immunity to Mtb. Mechanistically, IFN-I response dysregulates iron metabolism, depolarizes mitochondrial membrane potential, and induces cell death in myeloid progenitors. Finally, activation of IFN-I/iron axis in myeloid progenitors generates a detrimental trained immunity to Mtb infection. These results identify an unanticipated immune evasion strategy of Mtb in the bone marrow that controls the magnitude and anti-microbial capacity of innate immunity to infection
Project description:A greater understanding of hematopoietic stem cell (HSC) regulation is required for dissecting protective versus detrimental immunity to pathogens that cause chronic infections such as Mycobacterium tuberculosis (Mtb). We have shown that systemic administration of BCG or b-glucan reprograms HSCs in the BM via a type II interferon (IFN-II) or IL1 response, respectively, that confers protective trained immunity against Mtb. Yet, whether BCG/β-Glucan is unique in its ability to induce this protection remains unknown. Herein, we demonstrate that unlike BCG or b-glucan, Mtb reprograms HSCs via IFN-I response that suppresses myelopoiesis and impairs protective trained immunity to Mtb. Mechanistically, IFN-I response dysregulates iron metabolism, depolarizes mitochondrial membrane potential, and induces cell death in myeloid progenitors. Finally, activation of IFN-I/iron axis in myeloid progenitors generates a detrimental trained immunity to Mtb infection. These results identify an unanticipated immune evasion strategy of Mtb in the bone marrow that controls the magnitude and anti-microbial capacity of innate immunity to infection
Project description:To evaluate the DC genome-wide gene expression in response to beta-glucan and its regulation by IL-1 receptor antagonist (IL-1RA) we used a whole genome microarray. The gene expression profiling was performed in DC left untreated or exposed to beta-glucan for 4 and 12 h, in absence or presence of IL-1RA. This strategy allowed the identification of early/immediate and late/secondary genes regulated by beta-glucan in an IL-1-dependent and -independent manner. Human monocyte-derived DC were obtained by a 6/7-d cultures of freshly isolated monocytes with recombinant human IL-4 (10 ng/ml) and GM-CSF (50 ng/ml). Beta-glucan-associated gene expression and its regulation by IL-1RA in human DC was measured in cells left untreated or at 4 and 12 h after exposure to 10 ug/ml of particulate beta-glucan in absence or presence of 2.5 ug/ml of IL-1RA. Five different conditions (Untreated 0h, beta-glucan 4h, IL-1RA + beta-glucan 4h, beta-glucan 12h, and IL-1RA + beta-glucan 12h) were tested using DC from three different donors.
Project description:Extramedullary hematopoiesis (EMH) is an emerging player in peripheral tissue injury in autoimmune disorders. Here, we use the NZBW/F1 lupus mouse model to explore the contribution of EMH to disease pathogenesis of SLE. We demonstrate that EMH takes place in the spleen of F1-L mice and show it is correlated with the activity of lupus nephritis (LN). Transcriptomic analysis demonstrated that splenic hematopoietic stem and progenitor cells (HSPC) carry a higher inflammatory potential than their bone marrow counterparts. Administration of β-glucan, an inducer of innate immunity, exacerbated splenic EMH, increased neutrophil production and worsened LN. Transcriptomic signatures of HSPCs in SLE patients with high disease activity show changes similar to the ones observed in the lupus-prone mouse model. Overall, EMH and trained immunity are ubiquitous in SLE, contributing to disease pathogenesis by sustaining and amplifying the inflammatory response and increasing the risk for flare of the disease.
Project description:Extramedullary hematopoiesis (EMH) is an emerging player in peripheral tissue injury in autoimmune disorders. Here, we use the NZBW/F1 lupus mouse model to explore the contribution of EMH to disease pathogenesis of SLE. We demonstrate that EMH takes place in the spleen of F1-L mice and show it is correlated with the activity of lupus nephritis (LN). Transcriptomic analysis demonstrated that splenic hematopoietic stem and progenitor cells (HSPC) carry a higher inflammatory potential than their bone marrow counterparts. Administration of β-glucan, an inducer of innate immunity, exacerbated splenic EMH, increased neutrophil production and worsened LN. Transcriptomic signatures of HSPCs in SLE patients with high disease activity show changes similar to the ones observed in the lupus-prone mouse model. Overall, EMH and trained immunity are ubiquitous in SLE, contributing to disease pathogenesis by sustaining and amplifying the inflammatory response and increasing the risk for flare of the disease.
Project description:Hematopoietic stem cells give rise to all blood lineages, can fully re-populate the bone marrow, and easily outlive the host organism. To better understand how stem cells remain fit during aging, we analyzed the proteome of hematopoietic stem and progenitor cells.