The rockefeller university

Background: Recent single-cell studies indicated that IL-17-producing T cells (T17) have diverse subsets expressing IL-17A, IL-17F, or a combination in human psoriasis skin. However, it is unknown how T17 subsets are differently regulated by IL-23 versus IL-17A blockade. Objective: We sought to investigate how systemic monoclonal antibody injections blocking IL-23 versus IL-17A differently modify immune cell transcriptomes in human psoriasis skin. Methods: We analyzed a total of 93 human skin single-cell libraries, including 42 psoriasis pretreatment lesional skin, 25 psoriasis pretreatment nonlesional skin, 12 psoriasis posttreatment after IL-23 inhibition, 4 psoriasis posttreatment after IL-17A inhibition, and 10 control skin samples. ClinicalTrials.gov NCT04630652. Results: Of the six T17 subsets identified, an IL17A+IFNG+ subset and an IL17F+IL102 subset expressed the IL-23 receptor along with other inflammatory cytokines, and IL-23 inhibition downregulated these potentially pathogenic T17 subsets. In contrast, T17 cells expressing both IL-17A and IL-17F did not express the IL-23 receptor, and the percentage of this potentially nonpathogenic T17 subset increased after IL-23 inhibition. In addition, the expression of the IL-17-negative regulation genes, such as TNFAIP3, increased in myeloid cells more after IL-23 inhibition than after IL-17A inhibition. Conclusions: This study suggests multiple immune mechanisms of how IL-23 inhibition can modify the complex inflammatory environment present in psoriatic skin, highlighting the roles of specific T17 subsets in psoriasis development and background skin protection. (J Allergy Clin Immunol 2025;155:1898-912.)

The lack of T cells in tumors is a major hurdle to successful immune checkpoint therapy (ICT). Therefore, ther-apeutic strategies promoting T cell recruitment into tumors are warranted to improve the treatment efficacy. Here, we report that Fc-optimized anti-cytotoxic T lymphocyte antigen 4 (CTLA-4) antibodies are potent re-modelers of tumor vasculature that increase tumor-associated high endothelial venules (TA-HEVs), special-ized blood vessels supporting lymphocyte entry into tumors. Mechanistically, this effect is dependent on the Fc domain of anti-CTLA-4 antibodies and CD4+ T cells and involves interferon gamma (IFNy). Unexpectedly, we find that the human anti-CTLA-4 antibody ipilimumab fails to increase TA-HEVs in a humanized mouse model. However, increasing its Fc effector function rescues the modulation of TA-HEVs, promotes CD4+ and CD8+ T cell infiltration into tumors, and sensitizes recalcitrant tumors to programmed cell death protein 1 (PD-1) blockade. Our findings suggest that Fc-optimized anti-CTLA-4 antibodies could be used to repro-gram tumor vasculature in poorly immunogenic cold tumors and improve the efficacy of ICT.

PurposeIn the receptor organs of the inner ear, hair cells detect mechanical stimuli such as sounds and accelerations by deflection of their hair bundles. Myosin regulatory light chain (RLC) and non-muscle myosin II (NM2) are expressed at the apical surfaces of hair cells, and NM2 and the phosphorylation of RLC by myosin light chain kinase (MLCK) have earlier been shown to regulate the shapes of hair cells' apical surfaces in rodents. The aim of our study was to elucidate the function of myosin molecules on hair cell physiology.MethodsWe investigated the expression of NM2 and RLC in the bullfrog's saccule by immunostaining. Using NM2 and MLCK inhibitors, we measured the stiffness, spontaneous oscillation, and resting open probability of frog hair bundles. Six to ten saccules from pleural animals were used in each experiment. In addition, we recorded auditory brainstem responses in ten mice after transtympanic injection of an MLCK inhibitor.ResultsWe confirmed the expression of NM2A/B and MYL9 on the apical surfaces of hair cells and of NM2A and MYL12A in hair bundles. We found that NM2 and MLCK inhibitors reduce the stiffness of hair bundles from the bullfrog's saccule. Moreover, MLCK inhibition inhibits the spontaneous oscillation of hair bundles and increases the resting open probability of transduction channels. In addition, MLCK inhibition elevates hearing thresholds in mice.ConclusionWe conclude that NM2 and the phosphorylation of RLC modulate the physiological function of hair cells and thereby help to set the normal operating conditions of hair bundles.

Type III CRISPR-Cas systems defend against viral infection in prokaryotes by using an RNA-guided complex that recognizes foreign transcripts and synthesizes cyclic oligoadenylate (cOA) messengers to activate CRISPR-associated Rossmann-fold (CARF) immune effectors. In this study, we investigated a protein containing a CARF domain-fused Toll/interleukin-1 receptor (TIR) domain, Cat1. We found that Cat1 provides immunity by cleaving and depleting oxidized nicotinamide adenine dinucleotide (NAD+) molecules from the infected host, inducing a growth arrest that prevents viral propagation. Cat1 forms dimers that stack upon each other to generate long filaments that are maintained by bound cOA ligands, with stacked TIR domains forming the NAD+ cleavage catalytic sites. Furthermore, Cat1 filaments assemble into distinct trigonal and pentagonal networks that enhance NAD+ degradation. Cat1 presents an unprecedented chemistry and higher-order protein assembly for the CRISPR-Cas response.

The Fanconi anemia (FA) DNA repair pathway is required for the repair of DNA interstrand cross-links (ICLs). ICLs are caused by genotoxins, such as chemotherapeutic agents or reactive aldehydes. Inappropriately repaired ICLs contribute to hematopoietic stem cell (HSC) failure and tumorigenesis. While endogenous acetaldehyde and formaldehyde are known to induce HSC failure and leukemia in FA patients, the effects of other toxic metabolites on FA pathogenesis have not been systematically investigated. Using a metabolism-focused CRISPR screen, we found a synthetically lethal interaction between ALDH9A1 and the deficiency of the FA pathway. Combined deficiency of ALDH9A1 and FANCD2 causes genomic instability, apoptosis, and decreased hematopoietic colony formation. Fanca-/-Aldh9a1-/- mice exhibited an increased incidence of ovarian tumors. A suppressor CRISPR screen revealed that the loss of ATP13A3, a polyamine transporter, resulted in improved survival of FANCD2-/-ALDH9A1-/- cells. These findings nominate high intracellular polyamines and the resulting 3-aminopropanal and acrolein as sources of endogenous DNA damage in patients with FA.

Mass photometry (MP) is a label-free approach that measures the mass of single molecules in solution. Here, we discuss the principles of MP, example uses of the technique, and how it can be a valuable tool for structural biologists in streamlining cryoelectron microscopy (cryo-EM) pipelines.

Mutations in RNA splicing factors are prevalent across cancers and generate recurrently mis-spliced mRNA isoforms. Here, we identified a series of bona fide neoantigens translated from highly stereotyped splicing alterations promoted by neomorphic, leukemia-associated somatic splicing machinery mutations. We utilized feature-barcoded peptide-major histocompatibility complex (MHC) dextramers to isolate neoantigenreactive T cell receptors (TCRs) from healthy donors, patients with active myeloid malignancy, and following curative allogeneic stem cell transplant. Neoantigen-reactive CD8+ T cells were present in the blood of patients with active cancer and had a distinct phenotype from virus-reactive T cells with evidence of impaired cytotoxic function. T cells engineered with TCRs recognizing SRSF2 mutant-induced neoantigens arising from mis-splicing events in CLK3 and RHOT2 resulted in specific recognition and cytotoxicity of SRSF2-mutant leukemia. These data identify recurrent RNA mis-splicing events as sources of actionable public neoantigens in myeloid leukemias and provide proof of concept for genetically redirecting T cells to recognize these targets.

Introduction: Low-income and underserved populations, especially racial and ethnic minorities, experience health disparities linked to social determinants. The COVID-19 pandemic amplified these disparities, necessitating effective strategies to address structural racism and related factors. Vaccination, crucial for mitigating infectious diseases, including COVID-19 and influenza, remains challenging among underserved populations. Community health worker (CHW) interventions show promise in addressing these disparities but have not undergone rigorous evaluation with a randomized controlled trial to increase vaccination uptake among underserved populations. This study develops and evaluates a CHW vaccination behavior (CHW-VB) intervention to increase COVID-19 and influenza vaccination among adult patients in primary care settings. Methods: Tailoring of the Boost Your Health (Refuerza tu Salud) intervention is grounded in behavior change theory and integrates input from a Community Advisory Board. The study employs a patient randomized controlled trial design to test the effectiveness the CHW-VB intervention compared with usual care across six Federally Qualified Health Centers (FQHCs) in New York. Patients are being screened for eligibility (vaccinated but not up to date with the COVID-19 vaccine and have at least one of seven common chronic illnesses) and 800 are assessed at baseline and three months. Outcomes include COVID-19 vaccine (primary) and influenza vaccine (secondary) uptake. The study also evaluates intervention implementation using the RE-AIM model. Conclusion: Boost Your Health aims to increase COVID-19 and influenza vaccination among racially/ethnically diverse, underserved populations with chronic illness through the CHW-VB intervention, targeting critical gaps in vaccination uptake to reduce health disparities and increase health equity. Trial registration: (ClinicalTrials.gov NCT06156254).

Dengue virus (DENV) is a mosquito-transmitted flavivirus; there are four serotypes (DENV1-4) that co-circulate globally. Primary infection causes self-limiting febrile illness, but secondary infection by a heterologous serotype can predispose to severe dengue. Neutralizing antibodies are key mediators of long-term protection; however, cross-reactive, non-neutralizing antibodies can cause antibody-dependent enhancement (ADE) of infection, which contributes to severe dengue. Therefore, elicitation of a potent, broadly neutralizing antibody response against all four DENV serotypes is desired for vaccine design. Here, we developed nano-particle immunogens bearing engineered variants of the E glycoprotein DIII domain (DIII) in which epitopes targeted by non-neutralizing antibodies were mutated via structure-guided design and phage display. A two-component cocktail of these DIII variants elicited a broadly neutralizing response against all four DENV serotypes in mice and limited viremia in a DENV2 challenge model. These results provide insights into the design of broadly acting vaccines against DENV serotypes.