Notes From the Field: Dispensing of Oral Antiviral Drugs for Treatment of COVID-19 by Zip Code-Level Social Vulnerability - United States, December 23, 2021-August 28, 2022.

Equitable access to COVID-19 therapeutics is a critical aspect of the distribution program led by the U.S. Department of Health and Human Services (HHS).

Applying Lessons Learned From COVID-19 Therapeutic Trials to Improve Future ALI/ARDS Trials.

Host-directed therapeutics targeting immune dysregulation are considered the most promising approach to address the unmet clinical need for acute lung injury (ALI)/acute respiratory distress syndrome (ARDS) related to coronavirus disease 2019 (COVID-19). To better understand the current clinical study landscape and gaps in treating hospitalized patients with severe or critical COVID-19, we identified COVID-19 trials developing host-directed therapies registered at ClinicalTrials.gov and discussed the factors contributing to the success vs failure of these studies.

Dispensing of Oral Antiviral Drugs for Treatment of COVID-19 by Zip Code-Level Social Vulnerability - United States, December 23, 2021-May 21, 2022.

The COVID-19 pandemic has highlighted and exacerbated long-standing inequities in the social determinants of health (1-3). Ensuring equitable access to effective COVID-19 therapies is essential to reducing health disparities. Molnupiravir (Lagevrio) and nirmatrelvir/ritonavir (Paxlovid) are oral antiviral agents effective at preventing hospitalization and death in patients with mild to moderate COVID-19 who are at high risk* for progression to severe COVID-19 when initiated within 5 days of symptom onset.

Sepsis Among Medicare Beneficiaries: 3. The Methods, Models, and Forecasts of Sepsis, 2012-2018.

Objective: To evaluate the impact of sepsis, age, and comorbidities on death following an acute inpatient admission and to model and forecast inpatient and skilled nursing facility costs for Medicare beneficiaries during and subsequent to an acute inpatient sepsis admission.

Design: Analysis of paid Medicare claims via the Centers for Medicare & Medicaid Services DataLink Project (CMS) and leveraging the CMS-Hierarchical Condition Category risk adjustment model.

Setting: All U.

Sepsis Among Medicare Beneficiaries: 2. The Trajectories of Sepsis, 2012-2018.

Objectives: To distinguish characteristics of Medicare beneficiaries who will have an acute inpatient admission for sepsis from those who have an inpatient admission without sepsis, and to describe their further trajectories during and subsequent to those inpatient admissions.

Design: Analysis of paid Medicare claims via the Centers for Medicare and Medicaid Services DataLink Project.

Setting: All U.

Sepsis Among Medicare Beneficiaries: 1. The Burdens of Sepsis, 2012-2018.

Objectives: To provide contemporary estimates of the burdens (costs and mortality) associated with acute inpatient Medicare beneficiary admissions for sepsis.

Design: Analysis of paid Medicare claims via the Centers for Medicare & Medicaid Services DataLink Project.

Setting: All U.

Functional mimetic of the G-protein coupled receptor CXCR4 on a soluble antibody scaffold.

G-protein coupled receptors (GPCRs) constitute major drug targets due to their involvement in critical biological functions and pathophysiological disorders. The leading challenge in their structural and functional characterization has been the need for a lipid environment to accommodate their hydrophobic cores. Here, we report an antibody scaffold mimetic (ASM) platform where we have recapitulated the extracellular functional domains of the GPCR, C-X-C chemokine receptor 4 (CXCR4) on a soluble antibody framework.

Immune stealth-driven O2 serotype prevalence and potential for therapeutic antibodies against multidrug resistant Klebsiella pneumoniae.

Emerging multidrug-resistant bacteria are a challenge for modern medicine, but how these pathogens are so successful is not fully understood. Robust antibacterial vaccines have prevented and reduced resistance suggesting a pivotal role for immunity in deterring antibiotic resistance. Here, we show the increased prevalence of Klebsiella pneumoniae lipopolysaccharide O2 serotype strains in all major drug resistance groups correlating with a paucity of anti-O2 antibodies in human B cell repertoires.

Anti-LPS antibodies protect against Klebsiella pneumoniae by empowering neutrophil-mediated clearance without neutralizing TLR4.

Initial promising results with immune sera guided early human mAb approaches against Gram-negative sepsis to an LPS neutralization mechanism, but these efforts failed in human clinical trials. Emergence of multidrug resistance has renewed interest in pathogen-specific mAbs. We utilized a pair of antibodies targeting Klebsiella pneumoniae LPS, one that both neutralizes LPS/TLR4 signaling and mediates opsonophagocytic killing (OPK) (54H7) and one that only promotes OPK (KPE33), to better understand the contribution of each mechanism to mAb protection in an acutely lethal pneumonia model.

Anti-MrkA Monoclonal Antibodies Reveal Distinct Structural and Antigenic Features of MrkA.

Antibody therapy against antibiotics resistant Klebsiella pneumoniae infections represents a promising strategy, the success of which depends critically on the ability to identify appropriate antibody targets. Using a target-agnostic strategy, we recently discovered MrkA as a potential antibody target and vaccine antigen. Interestingly, the anti-MrkA monoclonal antibodies isolated through phage display and hybridoma platforms all recognize an overlapping epitope, which opens up important questions including whether monoclonal antibodies targeting different MrkA epitopes can be generated and if they possess different protective profiles.

Target-Agnostic Identification of Functional Monoclonal Antibodies Against Klebsiella pneumoniae Multimeric MrkA Fimbrial Subunit.

The increasing incidence of Klebsiella pneumoniae infections refractory to treatment with current broad-spectrum antibiotic classes warrants the exploration of alternative approaches, such as antibody therapy and/or vaccines, for prevention and treatment. However, the lack of validated targets shared by spectrums of clinical strains poses a significant challenge. We adopted a target-agnostic approach to identify protective antibodies against K.

Reprogramming of murine macrophages through TLR2 confers viral resistance via TRAF3-mediated, enhanced interferon production.

The cell surface/endosomal Toll-like Receptors (TLRs) are instrumental in initiating immune responses to both bacteria and viruses. With the exception of TLR2, all TLRs and cytosolic RIG-I-like receptors (RLRs) with known virus-derived ligands induce type I interferons (IFNs) in macrophages or dendritic cells. Herein, we report that prior ligation of TLR2, an event previously shown to induce "homo" or "hetero" tolerance, strongly "primes" macrophages for increased Type I IFN production in response to subsequent TLR/RLR signaling.

IRAK4 kinase activity is not required for induction of endotoxin tolerance but contributes to TLR2-mediated tolerance.

Prior exposure to LPS induces "endotoxin tolerance" that reprograms TLR4 responses to subsequent LPS challenge by altering expression of inflammatory mediators. Endotoxin tolerance is thought to limit the excessive cytokine storm and prevent tissue damage during sepsis but renders the host immunocompromised and susceptible to secondary infections. Tolerance initiated via one TLR can affect cellular responses to challenge via the same TLR ("homotolerance") or through different TLRs ("heterotolerance").

Complete dependence on IRAK4 kinase activity in TLR2, but not TLR4, signaling pathways underlies decreased cytokine production and increased susceptibility to Streptococcus pneumoniae infection in IRAK4 kinase-inactive mice.

IRAK4 is critical for MyD88-dependent TLR signaling, and patients with Irak4 mutations are extremely susceptible to recurrent bacterial infections. In these studies, mice homozygous for a mutant IRAK4 that lacks kinase activity (IRAK4(KDKI)) were used to address the role of IRAK4 in response to TLR agonists or bacterial infection. IRAK4(KDKI) macrophages exhibited diminished responsiveness to the TLR4 agonist LPS and little to no response to the TLR2 agonist Pam3Cys compared with wild-type macrophages as measured by cytokine mRNA, cytokine protein expression, and MAPK activation.

Proteinase-activated receptor 2 activation promotes an anti-inflammatory and alternatively activated phenotype in LPS-stimulated murine macrophages.

Proteinase-activated receptor 2 (PAR(2)), a 7-transmembrane G protein-coupled receptor, contributes to inflammation either positively or negatively in different experimental systems. Previously, we reported that concurrent activation of PAR(2) and TLRs in human lung and colonic epithelial cells resulted in a synergistic increase in NF-κB-mediated gene expression, but a down-regulation of IRF-3-mediated gene expression. In this study, the effect of PAR(2) activation on LPS-induced TLR4 signaling was examined in primary murine macrophages.

Histone methylation by NUE, a novel nuclear effector of the intracellular pathogen Chlamydia trachomatis.

Sequence analysis of the genome of the strict intracellular pathogen Chlamydia trachomatis revealed the presence of a SET domain containing protein, proteins that primarily function as histone methyltransferases. In these studies, we demonstrated secretion of this protein via a type III secretion mechanism. During infection, the protein is translocated to the host cell nucleus and associates with chromatin.

CCAAT/enhancer-binding protein beta and delta binding to CIITA promoters is associated with the inhibition of CIITA expression in response to Mycobacterium tuberculosis 19-kDa lipoprotein.

TLR2 signaling by Mycobacterium tuberculosis 19-kDa lipoprotein (LpqH) inhibits IFN-gamma-induced expression of CIITA by macrophages. Microarray analysis, quantitative RT-PCR, and Western blots showed that LpqH induced C/EBPbeta and C/EBPdelta in kinetic correlation with inhibition of CIITA expression. Of the C/EBPbeta isoforms, liver inhibitory protein (LIP) was notably induced and liver-activating protein was increased by LpqH.

Mycobacterium tuberculosis 19-kDa lipoprotein inhibits IFN-gamma-induced chromatin remodeling of MHC2TA by TLR2 and MAPK signaling.

During infection of macrophages, prolonged signaling by Mycobacterium tuberculosis (Mtb) or its 19-kDa lipoprotein (LpqH; Rv3763) inhibits IFN-gamma-induced expression of several immune function genes, including class II transactivator (CIITA), which regulates class II MHC. Mtb does not inhibit early IFN-gamma signaling events, e.g.

Prolonged toll-like receptor signaling by Mycobacterium tuberculosis and its 19-kilodalton lipoprotein inhibits gamma interferon-induced regulation of selected genes in macrophages.

Infection of macrophages with Mycobacterium tuberculosis or exposure to M. tuberculosis 19-kDa lipoprotein for >16 h inhibits gamma interferon (IFN-gamma)-induced major histocompatibility complex class II (MHC-II) expression by a mechanism involving Toll-like receptors (TLRs). M.

Inhibition of major histocompatibility complex II expression and antigen processing in murine alveolar macrophages by Mycobacterium bovis BCG and the 19-kilodalton mycobacterial lipoprotein.

Alveolar macrophages constitute a primary defense against Mycobacterium tuberculosis, but they are unable to control M. tuberculosis without acquired T-cell immunity. This study determined the antigen-presenting cell function of murine alveolar macrophages and the ability of the model mycobacterium, Mycobacterium bovis BCG, to modulate it.

CpG DNA induces a class II transactivator-independent increase in class II MHC by stabilizing class II MHC mRNA in B lymphocytes.

Microbial products, such as CpG DNA and LPS, enhance class II MHC (MHC-II) expression and Ag presentation by dendritic cells, but this effect does not occur with macrophages and is largely unexplored in B cells. Although MHC-II expression is influenced by transcriptional regulation, which is governed by class II transactivator (CIITA) in all cells, microbial products enhance MHC-II expression by dendritic cells in part by increasing MHC-II protein stability. In this study, we show that the CpG-induced increase in MHC-II expression by B lymphocytes is not due to protein stabilization or changes in CIITA expression or activity, but instead is due to increased stability of MHC-II mRNA.