Distinct antibody-based signatures and functionality distinguish latent and active pediatric tuberculosis.

Background: Tuberculosis (TB), caused by (Mtb), is among the leading causes of death from an infectious agent among children worldwide. Children represent a particularly vulnerable population due to the greater challenges in diagnosis and the higher risk of progression to severe forms of the disease. However, whether different pediatric outcomes relate to distinct immunologic responses remains incompletely understood.

Preclinical development and clinical safety assessment of a synthetic peptide conjugate enabling endogenous antibody binding to promote innate receptor engagement.

Peptide-based vaccines can be used to deliver tumor-specific antigens to dendritic cells (DCs), leading to tumor-directed T cell responses. We previously developed a peptide-peptide conjugate technology enabling cross-linking of pre-existing tetanus toxin-directed antibodies, facilitating antigen delivery to, and activation of DCs. To achieve this, multiple identical tetanus toxin-derived B cell epitopes (MTTEs) are conjugated to synthetically produce target antigens of choice.

HLA-E/peptide complexes differentially interact with NKG2A/CD94 and T cell receptors.

The virtually monomorphic antigen presentation molecule HLA-E can present self- and non-self peptides to the NKG2A/CD94 co-receptor inhibitory complex expressed on natural killer (NK) cells and to T cell receptors (TCRs) expressed on T cells. HLA-E presents self-peptides to NKG2A/CD94 to regulate tissue homeostasis, whereas HLA-E restricted T cells mediate regulatory and cytotoxic responses toward pathogen-infected cells. In this study, we directly compared HLA-E/peptide recognition and signaling between NKG2A/CD94 and 2 HLA-E restricted TCRs that can recognize self-peptides or identical peptide mimics from the viral UL40 protein of cytomegalovirus using position substituted peptide variants.

The role of IgA and IgG in Mycobacterium tuberculosis infection: A cross-sectional study in Ethiopia.

Introduction: Despite the high global prevalence of Mycobacterium tuberculosis (Mtb) infection in humans, most infected individuals achieve a stable immunological equilibrium, without showing clinical signs and symptoms of tuberculosis (TB). Although the role of antibodies in TB is assumed to be relatively small compared to cell-mediated immunity, their role in TB has been documented in a few recent studies.

Methods: In this cross-sectional study, we quantitated antibody responses to Mtb antigens, lipoarabinomannan (LAM), and heparin-binding hemagglutinin adhesin (HBHA) by determining antigen-specific immunoglobulin A(IgA) and G(IgG) secretion levels using enzyme-linked immunosorbent assay (ELISA) in serum and saliva of pulmonary TB patients (PTB), their household contacts (HHC), and community controls (CC) (determined by QuantiFERON TB Gold assay QFT- test result).

HLA-E/ specific CD4 and CD8 T cells have a memory phenotype in individuals with TB infection.

Introduction: Tuberculosis (TB) is the deadliest infectious disease worldwide and novel vaccines are urgently needed. HLA-E is a virtually monomorphic antigen presentation molecule and is not downregulated upon HIV co-infection. HLA-E restricted specific CD8 T cells are present in the circulation of individuals with active TB (aTB) and infection (TBI) with or without HIV co-infection, making HLA-E restricted T cells interesting vaccination targets for TB.

Evaluation of PLGA, lipid-PLGA hybrid nanoparticles, and cationic pH-sensitive liposomes as tuberculosis vaccine delivery systems in a Mycobacterium tuberculosis challenge mouse model - A comparison.

Tuberculosis (TB) continues to pose a global threat for millennia, currently affecting over 2 billion people and causing 10.6 million new cases and 1.3 million deaths annually.

specific HLA-E restricted T cells are induced during infection but not after BCG administration in non-human primates and humans.

Novel vaccines targeting the world's deadliest pathogen () are urgently needed as the efficacy of the Bacillus Calmette-Guérin (BCG) vaccine in its current use is limited. HLA-E is a virtually monomorphic unconventional antigen presentation molecule and HLA-E restricted specific CD8 T cells can control intracellular growth, making HLA-E a promising vaccine target for . In this study, we evaluated the frequency and phenotype of HLA-E restricted specific CD4/CD8 T cells in the circulation and bronchoalveolar lavage fluid of two independent non-human primate (NHP) studies and from humans receiving BCG either intradermally or mucosally.

HLA-E-tetramer-sorted CD8 T cells have a diverse TCR repertoire.

HLA-E molecules can present self- and pathogen-derived peptides to both natural killer (NK) cells and T cells. T cells that recognize HLA-E peptides via their T cell receptor (TCR) are termed donor-unrestricted T cells due to restricted allelic variation of HLA-E. The composition and repertoire of HLA-E TCRs is not known so far.

Corrigendum: Defining discriminatory antibody fingerprints in active and latent tuberculosis.

[This corrects the article DOI: 10.3389/fimmu.2022.

The MHC-E peptide ligands for checkpoint CD94/NKG2A are governed by inflammatory signals, whereas LILRB1/2 receptors are peptide indifferent.

The immune checkpoint NKG2A/CD94 is a promising target for cancer immunotherapy, and its ligand major histocompatibility complex E (MHC-E) is frequently upregulated in cancer. NKG2A/CD94-mediated inhibition of lymphocytes depends on the presence of specific leader peptides in MHC-E, but when and where they are presented in situ is unknown. We apply a nanobody specific for the Qdm/Qa-1 complex, the NKG2A/CD94 ligand in mouse, and find that presentation of Qdm peptide depends on every member of the endoplasmic reticulum-resident peptide loading complex.

Maternal HIV infection drives altered placental -specific antibody transfer.

Introduction: Placental transfer of maternal antibodies is essential for neonatal immunity over the first months of life. In the setting of maternal HIV infection, HIV-exposed uninfected (HEU) infants are at higher risk of developing severe infections, including active tuberculosis (TB). Given our emerging appreciation for the potential role of antibodies in the control of (), the bacteria that causes TB, here we aimed to determine whether maternal HIV status altered the quality of -specific placental antibody transfer.

Intranasal multivalent adenoviral-vectored vaccine protects against replicating and dormant M.tb in conventional and humanized mice.

Viral-vectored vaccines are highly amenable for respiratory mucosal delivery as a means of inducing much-needed mucosal immunity at the point of pathogen entry. Unfortunately, current monovalent viral-vectored tuberculosis (TB) vaccine candidates have failed to demonstrate satisfactory clinical protective efficacy. As such, there is a need to develop next-generation viral-vectored TB vaccine strategies which incorporate both vaccine antigen design and delivery route.

OX40 agonism enhances PD-L1 checkpoint blockade by shifting the cytotoxic T cell differentiation spectrum.

Immune checkpoint therapy (ICT) has the power to eradicate cancer, but the mechanisms that determine effective therapy-induced immune responses are not fully understood. Here, using high-dimensional single-cell profiling, we interrogate whether the landscape of T cell states in the peripheral blood predict responses to combinatorial targeting of the OX40 costimulatory and PD-1 inhibitory pathways. Single-cell RNA sequencing and mass cytometry expose systemic and dynamic activation states of therapy-responsive CD4 and CD8 T cells in tumor-bearing mice with expression of distinct natural killer (NK) cell receptors, granzymes, and chemokines/chemokine receptors.

Thermal-exchange HLA-E multimers reveal specificity in HLA-E and NKG2A/CD94 complex interactions.

There is growing interest in HLA-E-restricted T-cell responses as a possible novel, highly conserved, vaccination targets in the context of infectious and malignant diseases. The developing field of HLA multimers for the detection and study of peptide-specific T cells has allowed the in-depth study of TCR repertoires and molecular requirements for efficient antigen presentation and T-cell activation. In this study, we developed a method for efficient peptide thermal exchange on HLA-E monomers and multimers allowing the high-throughput production of HLA-E multimers.

Identification of HLA-E Binding -Derived Epitopes through Improved Prediction Models.

Tuberculosis (TB) remains one of the deadliest infectious diseases worldwide, posing great social and economic burden to affected countries. Novel vaccine approaches are needed to increase protective immunity against the causative agent (Mtb) and to reduce the development of active TB disease in latently infected individuals. Donor-unrestricted T cell responses represent such novel potential vaccine targets.

Development of Human Cell-Based Infection Models to Determine the Intracellular Survival of .

The () complex accounts for more than 80% of all pulmonary diseases caused by non-tuberculous mycobacteria (NTM) infections, which have an alarming increase in prevalence and vary in different regions, currently reaching 0.3-9.8 per 100,000 individuals.

A third vaccination with a single T cell epitope confers protection in a murine model of SARS-CoV-2 infection.

Understanding the mechanisms and impact of booster vaccinations are essential in the design and delivery of vaccination programs. Here we show that a three dose regimen of a synthetic peptide vaccine elicits an accruing CD8 T cell response against one SARS-CoV-2 Spike epitope. We see protection against lethal SARS-CoV-2 infection in the K18-hACE2 transgenic mouse model in the absence of neutralizing antibodies, but two dose approaches are insufficient to confer protection.

Defining Discriminatory Antibody Fingerprints in Active and Latent Tuberculosis.

Tuberculosis (TB) is among the leading causes of death worldwide from a single infectious agent, second only to COVID-19 in 2020. TB is caused by infection with (Mtb), that results either in a latent or active form of disease, the latter associated with Mtb spread. In the absence of an effective vaccine, epidemiologic modeling suggests that aggressive treatment of individuals with active TB (ATB) may curb spread.

An HLA-A*11:01-Binding Neoantigen from Mutated NPM1 as Target for TCR Gene Therapy in AML.

Acute myeloid leukemia (AML) is a hematological malignancy caused by clonal expansion of myeloid progenitor cells. Most patients with AML respond to chemotherapy, but relapses often occur and infer a very poor prognosis. Thirty to thirty-five percent of AMLs carry a four base pair insertion in the nucleophosmin 1 gene (NPM1) with a C-terminal alternative reading frame of 11 amino acids.

BCG-induced immunity profiles in household contacts of leprosy patients differentiate between protection and disease.

Leprosy is an infectious disease caused by Mycobacterium leprae leading to irreversible disabilities along with social exclusion. Leprosy is a spectral disease for which the clinical outcome after M. leprae infection is determined by host factors.

In-vivo expressed Mycobacterium tuberculosis antigens recognised in three mouse strains after infection and BCG vaccination.

Novel tuberculosis (TB)-vaccines preferably should (i) boost host immune responses induced by previous BCG vaccination and (ii) be directed against Mycobacterium tuberculosis (Mtb) proteins expressed throughout the Mtb infection-cycle. Human Mtb antigen-discovery screens identified antigens encoded by Mtb-genes highly expressed during in vivo murine infection (IVE-TB antigens). To translate these findings towards animal models, we determined which IVE-TB-antigens are recognised by T-cells following Mtb challenge or BCG vaccination in three different mouse strains.

IL-6 signaling in macrophages is required for immunotherapy-driven regression of tumors.

Background: High serum interleukin (IL-6) levels may cause resistance to immunotherapy by modulation of myeloid cells in the tumor microenvironment. IL-6 signaling blockade is tested in cancer, but as this inflammatory cytokine has pleiotropic effects, this treatment is not always effective.

Methods: IL-6 and IL-6R blockade was applied in an IL-6-mediated immunotherapy-resistant TC-1 tumor model (TC-1.

Interleukin-6 and Mycobacterium tuberculosis dormancy antigens improve diagnosis of tuberculosis.

Objectives: IFNγ-release assays (IGRAs) used for diagnosis of Mycobacterium (M.) tuberculosis infection have limited sensitivity. Alternative cytokines and M.