Microbes and Infection

A non-pathogenic Mycoplasma pneumoniae-based chassis is leading the development of live biotherapeutics (LBPs) for respiratory diseases. However, reports connecting Guillain-Barré syndrome (GBS) cases to prior M. pneumoniae infections represent a concern for exploiting such a chassis. Galactolipids, especially galactocerebroside (GalCer), are considered the most likely M. pneumoniae antigens triggering autoimmune responses associated with GBS development. In this work, we generated different strains lacking genes involved in galactolipids biosynthesis...

Fecal microbiota transplantation (FMT) is effective against recurrent Clostridioides difficile infection (rCDI), but its safety is jeopardized by the potential transmission of pathogens, so international guidelines recommend either a quarantine or a direct stool testing. Whereas reports of the quarantine-based approach are emerging, data on the direct testing-based approach are not available. Our aim is to report outcomes of a donor screening framework for FMT including direct stool testing. In this prospective cohort study, all donor candidates recruited at our FMT centre underwent a four-step screening process to be enrolled as actual donors...

Acinetobacter baumannii is an opportunistic bacterium that causes infection in several sites. Carbapenem-resistant A. baumannii strains (CRAb) lead the World Health Organization's list of 12 pathogens considered a priority for developing new antimicrobials. The pathogenicity of A. baumannii is related to the different virulence factors employed in the colonization of biotic and abiotic surfaces, biofilm formation and multidrug resistance. We analyze the outer membrane protein FilF from A. baumannii in silico and produce it in recombinant form (rFilF)...

To generate a new murine model for virus, DC-SIGN gene in murine was humanized. In this study, we successfully generated a humanized C57BL/6N mouse model expressing human DC-SIGN (hDC-SIGN) using CRISPR/Cas9 technology, and evaluated its characters and susceptibility to virus. The humanized mice could survival as usual, and with normal physiological index just like the wild-type mice. Whereas, we found significant differences in the intestinal flora and metabolic profiles between wild-type mice and humanized mice...

Vaccine adjuvants, such as liposome-based cationic adjuvant formulations (CAFs), are able to boost immune responses and, by incorporation of distinct immunomodulators, steer immunity towards a desired direction in mice, non-human primates and humans, while less studied in pigs. Here we used commercial pigs to investigate polarizing adjuvant effects of CAFs with immunomodulators: C-type lectin receptor ligands trehalose-6,6'-dibehenate and monomycolyl glycerol, toll-like receptor 3 ligand Poly(I:C) or retinoic acid...

Hemozoin is a crystal synthesized by Plasmodium parasites during hemoglobin digestion in the erythrocytic stage. The hemozoin released when the parasites egress from the red blood cell, which is complexed with parasite DNA, is cleared from the circulation by circulating and tissue-resident monocytes and macrophages, respectively. Recently, we reported that intravenous administration of purified hemozoin complexed with Plasmodium berghei DNA (HzPbDNA ) resulted in an innate immune response that blocked liver stage development of sporozoites that was dose-dependent and time-limited...

Over 300 years of research on the microbial world has revealed their importance in human health and disease. This review explores the impact and potential of microbial-based detection methods and therapeutic interventions, integrating research of early microbiologists, current findings, and future perspectives.

Our developed cell division-specific 'centrin' gene deleted Leishmania donovani (LdCen1-/- ) the causative parasite of the fatal visceral-leishmaniasis (VL), exhibits a selective growth arrest at the intracellular stage and is anticipated as a live attenuated vaccine candidate against VL. LdCen1-/- immunization in animals has shown increased IFN-γ secreting CD4+ and CD8+ T cells along with protection conferred by a protective proinflammatory immune response. A label-free proteomics approach has been employed to understand the physiology of infection and predict disease interceptors during Leishmania-host interactions...

PURPOSE: Few reports focused on the role of oral microbiome diversity in HIV infection. We characterized the microbiota-immunity axis in a cohort of treatment-naïve HIV-1-infected patients undergoing antiretroviral therapy (ART) focusing on the oral microbiome (OM) and immunological responsivity. METHODS: The sequencing of 16S rRNA V3-V4 hypervariable region was performed on salivary samples of 15 healthy control (HC) and 12 HIV+ patients before starting ART and after reaching virological suppression...

Zoonotic hepatitis E virus (HEV) infection is an emerging global public health concern, and understanding the dynamics of HEV transmission between animals and humans is crucial for public health. Animal models are critical to advancing the understanding of HEV pathogenesis, drug screening, vaccine development, and other related areas. Here, we provide an overview of recent studies investigating the cross-species transmission of HEV, and also delve into the current research and application of animal HEV infection models including non-human primates, rodents, pigs, and chickens, offering a comprehensive assessment of the advantages and disadvantages of each model...

The thymus plays a crucial role in T cell differentiation, a complex process influenced by various factors such as antigens, the microenvironment and thymic architecture. The way the thymus resolves infections is critical, as chronic persistence of microbes or inflammatory mediators can obstruct the differentiation. Here, we illustrate that following inflammatory T helper 1 infectious processes like those caused by C. albicans or T. cruzi, single positive thymocytes adopt a mature phenotype. Further investigations focused on T...

Zoonotic streptococci cause several invasive diseases with high mortality rates, especially meningitis. Numerous studies elucidated the meningitis pathogenesis of zoonotic streptococci, some specific to certain bacterial species. In contrast, others are shared among different bacterial species, involving colonization and invasion of mucosal barriers, survival in the bloodstream, breaching the blood-brain and/or blood-cerebrospinal fluid barrier to access the central nervous system, and triggering inflammation of the meninges...

Cerebral malaria (CM) induced by Plasmodium falciparum is a devastating neurological complication that may lead the patient to coma and death. This study aimed to protect Plasmodium-infected C57BL6 mice from CM by targeting the angiotensin II type 1 (AT1) receptor, which is considered the common connecting link between hypertension and CM. In CM, AT-1 mediates blood-brain barrier (BBB) damage through the overexpression of β-catenin. The AT-1-inhibiting drugs, such as irbesartan and losartan, were evaluated for the prevention of CM...

Global burden of infectious diseases and antimicrobial resistance are major public health issues calling for innovative control measures. Bacterial NAD kinase (NADK) is a crucial enzyme for production of NADP(H) and growth. In Staphylococcus aureus, NADK promotes pathogenesis by supporting production of key virulence determinants. Here, we find that knockdown of NADK by CRISPR interference sensitizes S. aureus to osmotic stress and to stresses induced by antibiotics targeting the envelop as well as replication, transcription and translation...

BACKGROUND: Little knowledge of antigen existence in the pulmonary tuberculosis (PTB) patient serum impeded its development in antigen detection technology, despite its considerable potential. METHODS: Human ligand proteins and their adsorbent Mycobacterium tuberculosis (M.tb) proteins in the serum of PTB patients were identified using human protein chip (HuProtTM ) and LC-MS/MS, successively. The monoclonal antibody of ligand proteins, C5orf24, and polyclonal antibody of 9 M...

Bats are important mammal reservoirs of zoonotic pathogens. However, due to research limitations involving species, locations, pathogens, or sample types, the full diversity of viruses in bats remains to be discovered. We used next-generation sequencing technology to characterize the mammalian virome and analyze the phylogenetic evolution and diversity of mammalian viruses carried by bats from Haikou City and Tunchang County in Hainan Province, China. We collected 200 pharyngeal swab and anal swab samples from Rhinolophus affinis, combining them into nine pools based on the sample type and collection location...

INTRODUCTION: Healthcare-acquired infections and overuse of antibiotics are a common problem. Rising emergence of antibiotic and antiseptic resistances requires new methods of microbial decontamination or decolonization as the use of far-UV-C radiation. METHODS: The microbicidal efficacy of UV-C radiation (222 nm, 233 nm, 254 nm) was determined in a quantitative carrier test and on a 3D-epidermis model against Staphylococcus (S.) aureus, S. epidermidis, S. haemolyticus, S...

Rabies virus (RABV) is a lethal neurotropic virus that causes 60,000 human deaths every year globally. RABV infection is characterized by the suppression of the interferon (IFN)-mediated antiviral response. However, molecular mechanisms leading to RABV sensing by RIG-I-like receptors (RLR) that initiates IFN signaling currently remain elusive. Here, we showed that RABV RNAs are primarily recognized by the RIG-I RLR, resulting in an IFN response in the infected cells, but this response varied according to the type of RABV used...

Human responses to vaccination are variable both within and between populations. Systems vaccinology, which is the application of multi-omics technologies to vaccine studies, seeks to understand such variation and predict responses to optimise vaccine strategies. Here we outline new approaches to systems vaccinology, focusing on the incorporation of additional cohorts, endpoints and technologies.

The discovery of bacterial microcolonies in tonsillar tissue of patients with tonsillar hyperplasia has raised the question of their role in provoking the local immune response. Tonsils collected from patients undergoing tonsillectomy were stained for three clinically relevant bacterial taxa and lymphocytes. The bacterial composition and abundance of microcolonies was investigated using a combination of laser-microdissection, amplicon sequencing and Droplet Digital PCR polymerase chain reaction. Microcolonies were detected in most samples (32/35) with a high prevalence of Haemophilus influenzae (78% of samples)...