Congenital iRHOM2 deficiency causes ADAM17 dysfunction and environmentally directed immunodysregulatory disease.

We report a pleiotropic disease due to loss-of-function mutations in RHBDF2, the gene encoding iRHOM2, in two kindreds with recurrent infections in different organs. One patient had recurrent pneumonia but no colon involvement, another had recurrent infectious hemorrhagic colitis but no lung involvement and the other two experienced recurrent respiratory infections. Loss of iRHOM2, a rhomboid superfamily member that regulates the ADAM17 metalloproteinase, caused defective ADAM17-dependent cleavage and release of cytokines, including tumor-necrosis factor and amphiregulin. To understand the diverse clinical phenotypes, we challenged Rhbdf2-/- mice with Pseudomonas aeruginosa by nasal gavage and observed more severe pneumonia, whereas infection with Citrobacter rodentium caused worse inflammatory colitis than in wild-type mice. The fecal microbiota in the colitis patient had characteristic oral species that can predispose to colitis. Thus, a human immunodeficiency arising from iRHOM2 deficiency causes divergent disease phenotypes that can involve the local microbial environment.

Early B cell factor 4 modulates FAS-mediated apoptosis and promotes cytotoxic function in human immune cells.

Apoptosis is a genetically regulated program of cell death that plays a key role in immune disease processes. We identified EBF4, a little-studied member of the early B cell factor (EBF) family of transcription factors, in a whole-genome CRISPR screen for regulators of Fas/APO-1/CD95-mediated T cell death. Loss of EBF4 increases the half-life of the c-FLIP protein, and its presence in the Fas signaling complex impairs caspase-8 cleavage and apoptosis. Transcriptome analysis revealed that EBF4 regulates molecules such as TBX21, EOMES, granzyme, and perforin that are important for human natural killer (NK) and CD8+ T cell functions. Proximity-dependent biotin identification (Bio-ID) mass spectrometry analyses showed EBF4 binding to STAT3, STAT5, and MAP kinase 3 and a strong pathway relationship to interleukin-2 regulated genes, which are known to govern cytotoxicity pathways. Chromatin immunoprecipitation and DNA sequencing analysis defined a canonical EBF4 binding motif, 5'-CCCNNGG/AG-3', closely related to the EBF1 binding site; using a luciferase-based reporter, we found a dose-dependent transcriptional response of this motif to EBF4. We also conducted assay for transposase-accessible chromatin sequencing in EBF4-overexpressing cells and found increased chromatin accessibility upstream of granzyme and perforin and in topologically associated domains in human lymphocytes. Finally, we discovered that the EBF4 has basal expression in human but not mouse NK cells and CD8+ T cells and vanishes following activating stimulation. Together, our data reveal key features of a previously unknown transcriptional regulator of human cytotoxic immune function.

Intrinsic and Extrinsic Control of the pKa of Thiol Guests inside Yoctoliter Containers.

Despite decades of research, there are still many open questions surrounding the mechanisms by which enzymes catalyze reactions. Understanding all the noncovalent forces involved has the potential to allow de novo catalysis design, and as a step toward this, understanding how to control the charge state of ionizable groups represents a powerful yet straightforward approach to probing complex systems. Here we utilize supramolecular capsules assembled via the hydrophobic effect to encapsulate guests and control their acidity. We find that the greatest influence on the acidity of bound guests is the location of the acidic group within the yoctoliter space. However, the nature of the electrostatic field generated by the (remote) charged solubilizing groups also plays a significant role in acidity, as does counterion complexation to the outer surfaces of the capsules. Taken together, these results suggest new ways by which to affect reactions in confined spaces.

Electrostatic Control of Macrocyclization Reactions within Nanospaces.

The intrinsic structural complexity of proteins makes it hard to identify the contributions of each noncovalent interaction behind the remarkable rate accelerations of enzymes. Coulombic forces are evidently primary, but despite developments in artificial nanoreactor design, a picture of the extent to which these can contribute has not been forthcoming. Here we report on two supramolecular capsules that possess structurally identical inner-spaces that differ in the electrostatic potential (EP) field that envelops them: one positive and one negative. This architecture means that only changes in the EP field influence the chemical properties of encapsulated species. We quantify these influences via acidity and rates of cyclization measurements for encapsulated guests, and we confirm the primary role of Coulombic forces with a simple mathematical model approximating the capsules as Born spheres within a continuum dielectric. These results reveal the reaction rate accelerations possible under Coulombic control and highlight important design criteria for nanoreactors.

Testosterone replacement therapy in patients with cachexia: a contemporary review of the literature.

INTRODUCTION: Patients with long-term chronic illnesses frequently present with hypogonadism, which is primarily managed through exogenous testosterone. These same patients also experience a high degree of cachexia, a loss of skeletal muscle and adipose tissue. OBJECTIVE: To perform a contemporary review of the literature to assess the effectiveness of testosterone replacement therapy (TRT) for managing chronic disease-associated cachexia. METHODS: We performed a PubMed literature search using MeSH terms to identify studies from 2000 to 2022 on TRT and the following cachexia-related chronic medical diseases: cancer, COPD, HIV/AIDS, and liver cirrhosis. RESULTS: From the literature, 11 primary studies and 1 meta-analysis were selected. Among these studies, 3 evaluated TRT on cancer-associated cachexia, 3 on chronic obstructive pulmonary disease, 4 on HIV and AIDS, and 2 on liver cirrhosis. TRT showed mixed results favoring clinical improvement on each disease. CONCLUSIONS: Cachexia is commonly observed in chronic disease states. Its occurrence with hypogonadism, alongside the shared symptoms of these 2 conditions, points toward the management of cachexia through the administration of exogenous testosterone. Robust data in the literature support the use of testosterone in increasing lean body mass, improving energy levels, and enhancing the quality of life for patients with chronic disease. However, the data are variable, and further studies are warranted on the long-term efficacy of TRT in patients with cachexia.