Project description:To determine the blood transcriptional response to intravenous (IV) BCG vaccination in rhesus macaques and identify correlates of vaccine-mediated protection against Mycobacterium tuberculosis (Mtb) challenge.
Project description:To determine the blood transcriptional response to BCG vaccination administered via different routes in rhesus macaques and identify correlates of vaccine-mediated protection against Mycobacterium tuberculosis (Mtb) challenge.
Project description:Vaccination against tuberculosis by intradermal Bacillus Calmette-Guérin (BCG) injection saves many lives, supposedly by inducing adaptive immune memory in lymphocytes. Epidemiologically, BCG vaccination is also associated with reduced childhood mortality unrelated to TB, which is attributed to innate immune memory, also termed trained immunity. We recently demonstrated improved protection against tuberculosis infection in highly susceptible rhesus macaques by mucosal BCG vaccination, correlating with a unique local but no peripheral immune profile. Here, we investigated local and peripheral innate immune function after intradermal versus mucosal vaccination with M. bovis BCG or the live attenuated, M. tuberculosis-derived candidate, MTBVAC. The results demonstrate an augmented frequency of trained immunity in monocytes after respiratory mucosal administration of live attenuated mycobacterial vaccines compared to intradermal immunization, with MTBVAC being equally potent as BCG. These results provide further support to strategies for improving TB vaccination and, more broadly, modulating innate immunity via mucosal surfaces.
Project description:Mycobacterium tuberculosis (Mtb) is the leading cause of death from infection worldwide. Intradermal (ID) vaccination with BCG has variable efficacy against pulmonary tuberculosis, the major cause of mortality and disease transmission. Here we show that the route and dose of BCG vaccination alters circulating and lung resident T cells and subsequent protection against Mtb challenge in nonhuman primates (NHP). NHP immunized with BCG by the intravenous (IV) route induced substantially higher antigen-specific CD4 (Th1 or Th17) and CD8 responses in blood, spleen, bronchoalveolar lavage (BAL), and lung lymph nodes compared to the same BCG dose administered by ID or aerosol (AE) routes. Moreover, IV immunization was the only route that induced a high frequency of antigen-specific tissue resident T cells in lung parenchyma. Six months after BCG vaccination, NHP were challenged with virulent Mtb. Strikingly, 9 of 10 NHP that received BCG IV were highly protected, with 6 NHP showing no detectable infection as determined by PET CT imaging, mycobacterial growth, pathology, granuloma formation, or de novo immune responses to Mtb-specific antigens. The finding that BCG IV prevents or significantly limits Mtb infection in NHP has important implications for vaccine development and provides a model for determining immune correlates and mechanisms of protection against TB.
Project description:COVID-19 continues to exact a toll on human health despite the availability of several vaccines. Bacillus Calmette Guérin (BCG) has been shown to confer heterologous immune protection against viral infections including COVID-19 and has been proposed as vaccine against SARS-CoV-2 (SCV2). Here we tested intravenous BCG vaccination against COVID-19 using the golden Syrian hamster model together with immune profiling and single cell RNA sequencing (scRNAseq). We observed that BCG vaccination conferred a modest reduction on lung SCV2 viral load, bronchopneumonia scores, and weight loss. This was accompanied by an increase in lung alveolar macrophages, a reversal of SCV2-mediated T cell lymphopenia, and reduced lung granulocytes. Single cell transcriptome profiling showed that BCG uniquely recruits immunoglobulin-producing plasma cells to the lung suggesting accelerated local antibody production. BCG vaccination also recruited elevated levels of Th1, Th17, Treg, CTLs, and Tmem cells, and differentially expressed gene (DEG) analysis showed a transcriptional shift away from exhaustion markers and towards antigen presentation and repair. Similarly, BCG enhanced lung recruitment of alveolar macrophages and reduced key interstitial macrophage subsets, with both cell-types also showing reduced IFN-associated gene expression. Our observations indicate that BCG vaccination protects against SCV2 immunopathology by promoting early lung immunoglobulin production and immunotolerizing transcriptional patterns among key myeloid and lymphoid populations.
Project description:The century-old Mycobacterium bovis Bacillus Calmette-Guerin (BCG) remains the only licensed vaccine against tuberculosis (TB). Despite this, there is still a lot to learn about the immune response induced by BCG, both in terms of phenotype and specificity. Here, we investigated the BCG-specific gene expression changes induced in PBMCs and CD4 memory T cells by BCG in individuals pre- and 8m post vaccination. We also determined whether reactivity against a peptide pool defined in individuals with controlled latent TB infection (MTB300), and with peptides homologous to peptides found in BCG, was boosted following BCG vaccination.
Project description:Rhesus macaques vaccinated by rhesus cytomegalovirus vectors expressing simian immunodeficiency virus proteins (RhCMV/SIV) activate gene expression signature associated with IL15. To examine the gene expression signature activated by IL15, we performed longitudinal examinations of rhesus macaques during IL15 treament.
Project description:Single cell RNA sequencing analysis was performed on bronchoalveolar lavage samples obtained from Rhesus macaques infected intranasally/intratracheally with SARS-CoV-2 after vaccination with mRNA-1273 vaccine