A CARD9 deficiency mouse model recapitulates human chronic CNS candidiasis identifying defective monocytic cell responses in immunopathogenesis.

Human Caspase Recruitment Domain Containing Protein 9 (CARD9) deficiency predisposes to invasive fungal disease, particularly by Candida spp. CARD9 deficiency causes chronic central nervous system (CNS) candidiasis. Currently, no animal model recapitulates the chronicity of disease, precluding a better understanding of immunopathogenesis.

Leaky Artemis Deficiency and EBV-Related Lymphoproliferative Disease: A Novel Case and Review of the Literature.

Introduction: Artemis () deficiency causes radiosensitive severe combined immunodeficiency (SCID), although hypomorphic cases can manifest later-onset immunodeficiency, autoimmunity, or lymphoproliferation. We report a 45-year-old man with humoral immunodeficiency, opportunistic infections, and recurrent EBV-positive diffuse large B-cell lymphoma (DLBCL).

Methods: Genetic analysis was performed to identify mutations in the gene.

Two rare mutations in homozygosity synergize to silence TREX1 in Aicardi-Goutières syndrome.

Background: Aicardi-Goutières syndrome (AGS) is a rare monogenic type I interferonopathy characterized by dysregulated inflammation and tissue damage that primarily affects the central nervous system. AGS is genetically diverse, with pathogenic variants across multiple genes, including TREX1, which drives excessive type I interferon (IFN) production.

Objective: This study investigated the genetic and molecular mechanisms underlying AGS in a family of two affected children, focusing on the role of variants in protein expression and dysregulation of the interferon pathway.

Card9 Broadly Regulates Host Immunity against Experimental Pulmonary 52D Infection.

The ubiquitous soil-associated fungus causes pneumonia that may progress to fatal meningitis. Recognition of fungal cell walls by C-type lectin receptors (CLRs) has been shown to trigger the host immune response. Caspase recruitment domain-containing protein 9 (Card9) is an intracellular adaptor that is downstream of several CLRs.

Gram-Negative Pneumonia Augments Non-Small Cell Lung Cancer Metastasis through Host Toll-like Receptor 4 Activation.

Introduction: Surgery is essential for cure of early-stage non-small cell lung cancer (NSCLC). Rates of postoperative bacterial pneumonias, however, remain high, and clinical data suggests that post-operative infectious complications confer an increased risk for metastasis. Toll-like receptors (TLRs) mediate the inflammatory response to infection by recognizing evolutionarily conserved bacterial structures at the surface of numerous pulmonary cell types; yet, little is known about how host TLR activation influences NSCLC metastasis.

Contribution of IL-1RI Signaling to Protection against 52D in a Mouse Model of Infection.

Interleukin-1 alpha (IL-1α) and interleukin-1 beta (IL-1β) are pro-inflammatory cytokines that are induced after infection and activate the interleukin-1 receptor type I (IL-1RI). To establish the role of IL-1RI signaling in protection against cryptococcal infection, we analyzed wild-type (WT) and IL-1RI-deficient (IL-1RI) mice on the BALB/c background. IL-1RI mice had significantly reduced survival compared to WT mice after intratracheal challenge with 52D.

Gram-positive pneumonia augments non-small cell lung cancer metastasis via host toll-like receptor 2 activation.

Surgical resection of early stage nonsmall cell lung cancer (NSCLC) is necessary for cure. However, rates of postoperative bacterial pneumonias remain high and may confer an increased risk for metastasis. Toll-like receptors (TLRs) mediate the inflammatory cascade by recognizing microbial products at the surface of numerous cell types in the lung; however, little is known about how host TLRs influence NSCLC metastasis.

The Cnes2 locus on mouse chromosome 17 regulates host defense against cryptococcal infection through pleiotropic effects on host immunity.

The genetic basis of natural susceptibility to progressive Cryptococcus neoformans infection is not well understood. Using C57BL/6 and CBA/J inbred mice, we previously identified three chromosomal regions associated with C. neoformans susceptibility (Cnes1, Cnes2, and Cnes3).

Unc93b1 -Dependent Endosomal Toll-Like Receptor Signaling Regulates Inflammation and Mortality during Coxsackievirus B3 Infection.

Coxsackievirus strain B serotype 3 (CVB3)-induced myocarditis is an important human disease that causes permanent tissue damage and can lead to death from acute infection or long-term morbidity caused by chronic inflammation. The timing and magnitude of immune activation following CVB3 infection can mediate a positive host outcome or increase tissue pathology. To better elucidate the role of endosomal Toll-like receptor (TLR) signaling in acute CVB3 infection, we studied mice with a loss-of-function mutation, known as Letr for 'loss of endosomal TLR response', in Unc93b1, which is a chaperone protein for TLR3, TLR7 and TLR9.

TLR4 and MyD88 control protection and pulmonary granulocytic recruitment in a murine intranasal RSV immunization and challenge model.

An intranasal vaccine composed of Toll-like receptor 2 (TLR2) ligand Neisseria meningitidis outer membrane proteins and Toll-like receptor 4 (TLR4) ligand Shigella flexneri lipopolysaccharide (LPS) (Protollin) and enriched respiratory syncytial virus (RSV) proteins (eRSV) has been demonstrated to promote balanced Th1/Th2 responses without eosinophil recruitment and to protect against challenge in mouse models. We used TLR2, TLR4 and myeloid differentiation factor 88 (MyD88) knock-out (-/-) mice to investigate the roles of these signalling pathways on immunogenicity, protection and pulmonary infiltrates following RSV immunization and challenge. Antigen-specific systemic and mucosal antibody production was significantly impaired only in TLR4-/- mice following Protollin-eRSV immunization.

Tlr5 is not primarily associated with susceptibility to Salmonella Typhimurium infection in MOLF/Ei mice.

The extreme susceptibility to infection with Salmonella Typhimurium of wild-derived MOLF/Ei mice has been linked to one genomic region on Chromosome 1 (Ity3). A member of the Toll-like receptors family, Tlr5, located on distal Chromosome 1, was previously shown to be a candidate gene for Ity3 based on expression studies and sequencing analysis. The candidacy of Tlr5 as a Salmonella-susceptibility gene was evaluated functionally by comparing Tlr5 C57BL/6J and MOLF/Ei alleles in vitro and in vivo.