Biology subjects

Kaufman, K. M.

Publications and source records attributed to Kaufman, K. M..

4 recordsLinked to original sources

bioRxiv2026

Hypoxia-inducible factor 2-alpha promotes fitness of cytokine-activated human natural killer cells

Natural Killer (NK) cells are innate effector cells with potent antiviral, antitumor, and immunoregulatory functions that are relevant for the treatment of human diseases. There is a pressing need to better understand the mechanisms governing cellular fitness and functional persistence of NK cells to generate therapeutics regimens of sufficient durability to achieve meaningful clinical benefit. Given the central role of interleukin-2 (IL-2) and IL-15 in the survival and proliferation of NK cells, we sought to identify transcription factors induced by these cytokines that are essential for maintaining the fitness of human NK cells from healthy human blood donors. Culture in IL-2 or IL-15 increased protein expression of hypoxia inducible factor 2 alpha (HIF-2, encoded by EPAS1) but not HIF-1 in NK cells. Unexpectedly, induction of HIF-2 was not dependent on limited oxygen availability. CRISPR targeting of EPAS1 or pharmacological inhibition of HIF-2 protein expression markedly compromised the survival of cytokine-activated human NK cells. In contrast, inhibition of canonical HIF-2 transcription factor activity via blocking HIF-2/HIF-1{beta} heterodimer formation had no apparent effects on NK cell viability, function, or metabolism. These results suggest that cytokines, rather than hypoxia, activate an unconventional HIF-1{beta} independent, HIF-2 pathway that helps to maintain NK cells during cellular activation, revealing the potential promise of manipulating HIF-2 to improve the efficacy of adoptive NK cell therapies.

immunology↗

bioRxiv2024

Human cytomegalovirus extensively re-organizes the human genome, diminishing TEAD1 transcription factor activity

Human cytomegalovirus (HCMV) infects up to 80% of the worlds population. Here, we show that HCMV infection leads to widespread changes in human chromatin accessibility and chromatin looping, with hundreds of thousands of genomic regions affected 48 hours after infection. Integrative analyses reveal HCMV-induced perturbation of Hippo signaling through drastic reduction of TEAD1 transcription factor activity. We confirm extensive concordant loss of TEAD1 binding, active H3K27ac histone marks, and chromatin looping interactions upon infection. Our data position TEAD1 at the top of a hierarchy involving multiple altered important developmental pathways. HCMV infection reduces TEAD1 activity through four distinct mechanisms: closing of TEAD1-bound chromatin, reduction of YAP1 and phosphorylated YAP1 levels, reduction of TEAD1 transcript and protein levels, and alteration of TEAD1 exon-6 usage. Altered TEAD1-based mechanisms are highly enriched at genetic risk loci associated with eye and ear development, providing mechanistic insight into HCMVs established roles in these processes.

genomics↗

bioRxiv2021

CRISPRa screen on a genetic risk locus shared by multiple autoimmune diseases identifies a dysfunctional enhancer that affects IRF8 expression through cooperative lncRNA and DNA methylation machinery

Dysregulated transcription factors represent a major class of drug targets that mediate the abnormal expression of many critical genes involved in SLE and other autoimmune diseases. Although strong evidence suggests that natural human genetic variation affects basal and inducible gene expression, it is still a considerable challenge to establish a biological link between GWAS-identified non-coding genetic risk variants and their regulated gene targets. Here, we combine genetic data, epigenomic data, and CRISPR activation (CRISPRa) assays to screen for functional variants regulating IRF8 expression. Using CRISPR-mediated deletion and 3D chromatin structure analysis, we demonstrate that the locus containing rs2280381 is a cell-type-specific distal enhancer for IRF8 that spatially interacts with the IRF8 promoter. Further, rs2280381 mediates IRF8 expression through enhancer RNA AC092723.1, which recruits TET1 to the IRF8 promoter to modulate IRF8 expression by affecting methylation levels. The alleles of rs2280381 modulate PU.1 binding and chromatin state to differentially regulate AC092723.1 and IRF8 expression. Our work illustrates a strategy to define the functional genetic variants modulating transcription factor gene expression levels and identifies the biologic mechanism by which autoimmune diseases risk genetic variants contribute to the pathogenesis of disease.

genetics↗

bioRxiv2019

Complement component 4 genes contribute sex-specific vulnerability in diverse illnesses

Many common illnesses differentially affect men and women for unknown reasons. The autoimmune diseases lupus and Sjogrens syndrome affect nine times more women than men1,2, whereas schizophrenia affects men more frequently and severely3-5. All three illnesses have their strongest common-genetic associations in the Major Histocompatibility Complex (MHC) locus, an association that in lupus and Sjogrens syndrome has long been thought to arise from HLA alleles6-13. Here we show that the complement component 4 (C4) genes in the MHC locus, recently found to increase risk for schizophrenia14, generate 7-fold variation in risk for lupus (95% CI: 5.88-8.61; p < 10-117 in total) and 16-fold variation in risk for Sjogrens syndrome (95% CI: 8.59-30.89; p < 10-23 in total), with C4A protecting more strongly than C4B in both illnesses. The same alleles that increase risk for schizophrenia, greatly reduced risk for lupus and Sjogrens syndrome. In all three illnesses, C4 alleles acted more strongly in men than in women: common combinations of C4A and C4B generated 14-fold variation in risk for lupus and 31-fold variation in risk for Sjogrens syndrome in men (vs. 6-fold and 15-fold among women respectively) and affected schizophrenia risk about twice as strongly in men as in women. At a protein level, both C4 and its effector (C3) were present at greater levels in men than women in cerebrospinal fluid (p < 10-5 for both C4 and C3) and plasma among adults ages 20-5015-17, corresponding to the ages of differential disease vulnerability. Sex differences in complement protein levels may help explain the larger effects of C4 alleles in men, womens greater risk of SLE and Sjogrens, and mens greater vulnerability in schizophrenia. These results nominate the complement system as a source of sexual dimorphism in vulnerability to diverse illnesses.

genetics↗