Design of Miniprotein Inhibitors of Bacterial Adhesins.

The rise of multidrug-resistant bacterial infections necessitates the discovery of novel antimicrobial strategies. Here, we show that protein design provides a generalizable means of generating new antimicrobials by neutralizing the function of bacterial adhesins, which are virulence factors critical in host-pathogen interactions. We designed high-affinity miniprotein binders to FimH and Abp1D/Abp2D chaperone usher pili adhesins from uropathogenic and , respectively, which are implicated in mediating both uncomplicated and catheter-associated urinary tract infections (UTI) responsible for significant morbidity and mortality worldwide.

Vaccination with Acinetobacter baumannii adhesin Abp2D provides protection against catheter-associated urinary tract infection.

Catheter-associated urinary tract infections (CAUTIs) contribute greatly to the burden of healthcare-associated infections. Acinetobacter baumannii is a Gram-negative bacterium with high levels of antibiotic resistance that is of increasing concern as a CAUTI pathogen. A.

Monoclonal antibodies targeting the FimH adhesin protect against uropathogenic UTI.

As antimicrobial resistance increases, urinary tract infections (UTIs) are expected to pose an increased burden in morbidity and expense on the health care system, increasing the need for alternative antibiotic-sparing treatments. Most UTIs are caused by uropathogenic (UPEC), whereas causes a large portion of non-UPEC UTIs. Both bacteria express type 1 pili tipped with the mannose-binding FimH adhesin critical for UTI pathogenesis.

Binding antibody titers against the hemagglutinin and neuraminidase correlate with protection against medically attended influenza A and B disease.

Human challenge and cohort studies have identified various correlates of protection (CoP) against influenza A and B viruses (IAV/IBV). However, associations with viral load, investigation of mucosal CoPs, and CoPs against IBV are limited in the context of natural infections. Plasma and nasal swabs were collected (2017-2020) from 56 adults diagnosed with IAV ( = 25 H1N1, = 19 H3N2) or IBV ( = 9 B/Victoria, = 3 B/Yamagata) in the emergency department.

Vaccination against influenza viruses annually: Renewing or narrowing the protective shield?

Annual vaccines are recommended for the seasonal influenza virus. While yearly updates to the vaccine are necessary due to the constant evolution of influenza viruses, some studies have suggested repeat vaccination may result in a reduction in vaccine effectiveness in subsequent years. This review examines the available evidence that repeated annual influenza virus vaccination may have effects on future vaccine responses, and it synthesizes the available data with studies that may indicate potential immunological mechanisms underlying these effects.

Identification of a seasonal influenza vaccine-induced broadly protective neuraminidase antibody.

Seasonal influenza viruses cause significant global illness and death annually, and the potential spillover of avian H5N1 poses a serious pandemic threat. Traditional influenza vaccines target the variable hemagglutinin (HA) protein, necessitating annual vaccine updates, while the slower-evolving neuraminidase (NA) presents a promising target for broader protection. We investigated the breadth of anti-NA B cell responses to seasonal influenza vaccination in humans.

Monoclonal antibodies targeting the FimH adhesin protect against uropathogenic UTI.

As antimicrobial resistance increases, urinary tract infections (UTIs) are expected to pose an increased burden in morbidity and expense on the healthcare system, increasing the need for alternative antibiotic-sparing treatments. Most UTIs are caused by uropathogenic (UPEC), while causes a significant portion of non-UPEC UTIs. Both bacteria express type 1 pili tipped with the mannose-binding FimH adhesin critical for UTI pathogenesis.

Defining a highly conserved B cell epitope in the receptor binding motif of SARS-CoV-2 spike glycoprotein.

SARS-CoV-2 mRNA vaccines induce robust and persistent germinal centre (GC) B cell responses in humans. It remains unclear how the continuous evolution of the virus impacts the breadth of the induced GC B cell response. Using ultrasound-guided fine needle aspiration, we examined draining lymph nodes of nine healthy adults following bivalent booster immunization.

mRNA-based influenza vaccine expands breadth of B cell response in humans.

Eliciting broad and durable antibody responses against rapidly evolving pathogens like influenza viruses remains a formidable challenge. The germinal center (GC) reaction enables the immune system to generate broad, high-affinity, and durable antibody responses to vaccination. mRNA-based severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccines induce persistent GC B cell responses in humans.

Repeat modules and N-linked glycans define structure and antigenicity of a critical enterotoxigenic E. coli adhesin.

Enterotoxigenic Escherichia coli (ETEC) cause hundreds of millions of cases of infectious diarrhea annually, predominantly in children from low-middle income regions. Notably, in children, as well as volunteers challenged with ETEC, diarrheal severity is significantly increased in blood group A (bgA) individuals. EtpA, is a secreted glycoprotein adhesin that functions as a blood group A lectin to promote critical interactions between ETEC and blood group A glycans on intestinal epithelia for effective bacterial adhesion and toxin delivery.

Immunogenicity and efficacy of XBB.1.5 rS vaccine against the EG.5.1 variant of SARS-CoV-2 in Syrian hamsters.

Unlabelled: The continued emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants necessitates updating coronavirus disease 2019 (COVID-19) vaccines to match circulating strains. The immunogenicity and efficacy of these vaccines must be tested in pre-clinical animal models. In Syrian hamsters, we measured the humoral and cellular immune response after immunization with the nanoparticle recombinant Spike (S) protein-based COVID-19 vaccine (Novavax, Inc.

CD4 T cells exhibit distinct transcriptional phenotypes in the lymph nodes and blood following mRNA vaccination in humans.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and mRNA vaccination induce robust CD4 T cell responses. Using single-cell transcriptomics, here, we evaluated CD4 T cells specific for the SARS-CoV-2 spike protein in the blood and draining lymph nodes (dLNs) of individuals 3 months and 6 months after vaccination with the BNT162b2 mRNA vaccine. We analyzed 1,277 spike-specific CD4 T cells, including 238 defined using Trex, a deep learning-based reverse epitope mapping method to predict antigen specificity.

Influenza vaccination stimulates maturation of the human T follicular helper cell response.

The differentiation and specificity of human CD4 T follicular helper cells (T cells) after influenza vaccination have been poorly defined. Here we profiled blood and draining lymph node (LN) samples from human volunteers for over 2 years after two influenza vaccines were administered 1 year apart to define the evolution of the CD4 T cell response. The first vaccination induced an increase in the frequency of circulating T (cT) and LN T cells at week 1 postvaccination.

Receptor Binding Specificity of a Bovine A(H5N1) Influenza Virus.

Outbreaks in the US of highly pathogenic avian influenza virus (H5N1) in dairy cows have been occurring for months creating new possibilities for direct contact between the virus and humans. Eisfeld examined the pathogenicity and transmissibility of a bovine HPAI H5N1 virus isolated from New Mexico in a series of and assays. They found the virus has a dual human- and avian virus-like receptor-binding specificity as measured in a solid phase glycan binding assay.

Maturation of germinal center B cells after influenza virus vaccination in humans.

Germinal centers (GC) are microanatomical lymphoid structures where affinity-matured memory B cells and long-lived bone marrow plasma cells are primarily generated. It is unclear how the maturation of B cells within the GC impacts the breadth and durability of B cell responses to influenza vaccination in humans. We used fine needle aspiration of draining lymph nodes to longitudinally track antigen-specific GC B cell responses to seasonal influenza vaccination.

Repeat modules and N-linked glycans define structure and antigenicity of a critical enterotoxigenic .

Enterotoxigenic (ETEC) cause hundreds of millions of cases of infectious diarrhea annually, predominantly in children from low-middle income regions. Notably, in children, as well as human volunteers challenged with ETEC, diarrheal severity is significantly increased severity in blood group A (bgA) individuals. EtpA, is a secreted glycoprotein adhesin that functions as a blood group A lectin to promote critical interactions between ETEC and blood group A glycans on intestinal epithelia for effective bacterial adhesion and toxin delivery.

Quantitative SARS-CoV-2 RT-PCR and Bronchoalveolar Cytokine Concentrations Redefine the COVID-19 Phenotypes in Critically Ill Patients.

Rationale: Recent studies suggest that both hypo- and hyperinflammatory acute respiratory distress syndrome (ARDS) phenotypes characterize severe COVID-19-related pneumonia. The role of lung Severe Acute Respiratory Syndrome - Coronavirus 2 (SARS-CoV-2) viral load in contributing to these phenotypes remains unknown.

Objectives: To redefine COVID-19 ARDS phenotypes when considering quantitative SARS-CoV-2 RT-PCR in the bronchoalveolar lavage of intubated patients.

Immunogenicity and efficacy of XBB.1.5 rS vaccine against EG.5.1 variant of SARS-CoV-2 in Syrian hamsters.

The continued emergence of SARS-CoV-2 variants necessitates updating COVID-19 vaccines to match circulating strains. The immunogenicity and efficacy of these vaccines must be tested in pre-clinical animal models. In Syrian hamsters, we measured the humoral and cellular immune response after immunization with the nanoparticle recombinant Spike (S) protein-based COVID-19 vaccine (Novavax, Inc.

Immunoglobulin replacement products protect against SARS-CoV-2 infection in vivo despite poor neutralizing activity.

Immunoglobulin (IG) replacement products are used routinely in patients with immune deficiency and other immune dysregulation disorders who have poor responses to vaccination and require passive immunity conferred by commercial antibody products. The binding, neutralizing, and protective activity of intravenously administered IG against SARS-CoV-2 emerging variants remains unknown. Here, we tested 198 different IG products manufactured from December 2019 to August 2022.

Targeting neuraminidase: the next frontier for broadly protective influenza vaccines.

Current seasonal influenza vaccines, which mainly target hemagglutinin (HA), require annual updates due to the continuous antigenic drift of the influenza virus. Developing an influenza vaccine with increased breadth of protection will have significant public health benefits. The recent discovery of broadly protective antibodies to neuraminidase (NA) has provided important insights into developing a universal influenza vaccine, either by improving seasonal influenza vaccines or designing novel immunogens.

CD62L expression marks a functionally distinct subset of memory B cells.

The memory B cell response consists of phenotypically distinct subsets that differ in their ability to respond upon antigen re-encounter. However, the pathways regulating the development and function of memory B cell subsets are poorly understood. Here, we show that CD62L and CD44 are progressively expressed on mouse memory B cells and identify transcriptionally and functionally distinct memory B cell subsets.

Leveraging vaccination-induced protective antibodies to define conserved epitopes on influenza N2 neuraminidase.

There is growing appreciation for neuraminidase (NA) as an influenza vaccine target; however, its antigenicity remains poorly characterized. In this study, we isolated three broadly reactive N2 antibodies from the plasmablasts of a single vaccinee, including one that cross-reacts with NAs from seasonal H3N2 strains spanning five decades. Although these three antibodies have diverse germline usages, they recognize similar epitopes that are distant from the NA active site and instead involve the highly conserved underside of NA head domain.