Microbes and Infection

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)...

Recent advances in organoid and organ-on-chip (OoC) technologies offer an unprecedented level of tissue mimicry. These models can recapitulate the diversity of cellular composition, 3D organization, and mechanical stimulation. These approaches are intensively used to understand complex diseases. This review focuses on the latest advances in this field to study host-microorganism interactions.

OBJECTS: As periodontitis progresses, the oral microbiome changes dynamically. The aim of this study was to evaluate the dominant bacteria of adults with stage III periodontitis and investigate potential pathways related to the dominant bacteria. MATERIALS AND METHODS: 16S rRNA sequencing was carried out to detect the differences in the oral bacteria between adult with stage Ⅰ and stage Ⅲ periodontitis and find the dominant bacteria in each group. The inhibitor of the predominant pathway for stage Ⅲ periodontitis was used to investigate the role of the dominant bacteria in periodontitis in vivo and in vitro...

BACKGROUND: The characteristics of colorectal cancer (CRC) vary depending on the level of study and clinical application. The current study proposed a novel subtype, Human papillomavirus (HPV)-infected CRC, to understand the impact of HPV on CRC. METHODS: We assessed the prevalence and clinical implications of HPV in CRC by integrating a single cohort in Guangdong Provincial People's Hospital and the public dataset. Differential gene, pathway enrichment analysis, and immune infiltration analysis were conducted to explore the patterns in HPV-infected CRC...

Single-cell genomics provide researchers with tools to assess host-pathogen interactions at a resolution previously inaccessible. Transcriptome analysis, epigenome analysis, and immune profiling techniques allow for a better comprehension of the heterogeneity underlying both the host response and infectious agents. Here, we highlight technological advancements and data analysis workflows that increase our understanding of host-pathogen interactions at the single-cell level. We review various studies that have used these tools to better understand host-pathogen dynamics in a variety of infectious disease contexts, including viral, bacterial, and parasitic diseases...

Parasitic diseases remain a major global health problem for humans. Parasites employ a variety of strategies to invade and survive within their hosts and to manipulate host defense mechanisms, always in the pathogen's favor. Extracellular vesicles (EVs), membrane-bound nanospheres carrying a variety of bioactive compounds, were shown to be released by the parasites during all stages of the infection, enabling growth and expansion within the host and adaptation to frequently changing environmental stressors...

Listeria monocytogenes, a contaminant of raw milk, includes hypervirulent clonal complexes (CC) like CC1, CC4, and CC6, highly overrepresented in dairy products when compared to other food types. Whether their higher prevalence in dairy products is the consequence of a growth advantage in this food remains unknown. We examined growth kinetics of five L. monocytogenes isolates (CC1, CC4, CC6, CC9, and CC121) at 37 and 4 °C in ultra-high temperature (UHT) milk and raw milk. At 4 °C, hypovirulent CC9 and CC121 isolates exhibit better growth parameters in UHT milk compared to the hypervirulent CC1, CC4, and CC6 isolates...

We evaluated whether viable and non-viable Lacticaseibacillus rhamnosus CRL1505 (Lr05V or Lr05NV, respectively) was able to improve emergency myelopoiesis induced by Streptococcus pneumoniae (Sp) infection. Adult Swiss-mice were orally treated with Lr05V or Lr05NV during five consecutive days. The Lr05V and Lr05NV groups and untreated control group received an intraperitoneal dose of cyclophosphamide (Cy-150 mg/kg). Then, the mice were nasally challenged with Sp (107 UFC/mice) on day 3 post-Cy injection...

Staphylococcus aureus is one of the major pathogens isolated from the airways of people with cystic fibrosis (pwCF). Recently, we described a mucoid S. aureus phenotype from respiratory specimens of pwCF, which constitutively overproduced biofilm that consisted of polysaccharide intercellular adhesin (PIA) due to a 5bp-deletion (5bp-del) in the intergenic region of the intercellular adhesin (ica) locus. Since we were not able to identify the 5bp-del in mucoid isolates of two pwCF with long-term S. aureus persistence and in a number of mucoid isolates of pwCF from a prospective multicenter study, these strains were (i) characterized phenotypically, (ii) investigated for biofilm formation, and (iii) molecular typed by spa-sequence typing...

Parasitic diseases are still a major public health problem especially among individuals of low socioeconomic status in underdeveloped countries. In recent years it has been demonstrated that parasites can release extracellular vesicles that participate in the host-parasite communication, immune evasion, and in governing processes associated with host infection. Extracellular vesicles are membrane-bound structures released into the extracellular space that can carry several types of biomolecules, including proteins, lipids, nucleic acids, and metabolites, which directly impact the target cells...

This review explores 'microb-aging' in the gut and its potential link to frailty aging. We explore this connection through alterations in microbiota's taxonomy and metabolism, as well as with concepts of ecological resilience, pathobionts emergence, and biogeography. We examine microb-aging in interconnected body organs, emphasizing the bidirectional relationship with 'inflammaging'. Finally, we discuss how targeting microb-aging could improve screening, diagnostic, and therapeutic approaches in geriatrics.