Neutrophil-suppressive activity over T-cell proliferation and fungal clearance in a murine model of Fonsecaea pedrosoi infection.

Neutrophils are essential to control several fungal infections. These cells are commonly known for their pro-inflammatory activities. However, some studies have demonstrated the anti-inflammatory properties of neutrophils during certain infectious diseases, culminating in the inhibition of T cell proliferation.

The impact of the absence of Toll-like receptor-2 during Sporothrix brasiliensis infection.

Purpose: Sporothrix brasiliensis, a member of the Sporothrix schenckii complex, is a major cause of epidemic outbreaks of sporotrichosis due to its greater virulence and ability to evade the immune system. The absence of studies about this species led to this study, with the aim to evaluate the importance of Toll-like receptor-2 (TLR-2) during S. brasiliensis infection.

The importance of Toll-like receptor 4 during experimental Sporothrix brasiliensis infection.

Here we investigated the importance of Toll-like receptor 4 (TLR-4) in innate immune response to Sporothrix brasiliensis, a virulent fungus of Sporothrix spp. In vitro assays, using C57Bl/6 (wild type [WT]) bone marrow-derived macrophages (BMDMs), and TLR-4 knockout (TLR-4-/-) showed that the absence of TLR-4 resulted in impaired phagocytosis and lower levels of tumor necrosis factor α (TNF-α), interleukin (IL)-6, and nitric oxide. In vivo assays were also performed, and the mice (WT and TLR-4-/-) were intraperitoneally infected with S.

An In Vitro Model for the Study of the Macrophage Response Upon Trichophyton rubrum Challenge.

Diversity in the macrophage models currently employed in immunology studies may lead to opposed results and interpretations. In this study, we aimed to analyze the suitability of J774 macrophage-like cells as a model for the interaction between the dermatophyte Trichophyton rubrum and macrophages. J774 cells were competent in fungal phagocytosis, but succumbed to hyphal growth.

IL-1 signaling inhibits Trichophyton rubrum conidia development and modulates the IL-17 response in vivo.

Dermatophytosis are one of the most common fungal infections in the world. They compromise keratinized tissues and the main etiological agent is Trichophyton rubrum. Macrophages are key cells in innate immunity and prominent sources of IL-1β, a potent inflammatory cytokine whose main production pathway is by the activation of inflammasomes and caspase-1.

Recognition of enteroinvasive Escherichia coli and Shigella flexneri by dendritic cells: distinct dendritic cell activation states.

The innate and adaptive immune responses of dendritic cells (DCs) to enteroinvasive Escherichia coli (EIEC) infection were compared with DC responses to Shigella flexneri infection. EIEC triggered DCs to produce interleukin (IL)-10, IL-12 and tumour necrosis factor (TNF)-α, whereas S. flexneri induced only the production of TNF-α.

Enteroinvasive Escherichia coli vs. Shigella flexneri: how different patterns of gene expression affect virulence.

Important features of the enteroinvasive Escherichia coli (EIEC) phenotype and gene expression likely to confer EIEC with a lower ability to cause disease than Shigella flexneri were described here for the first time. To confirm the lower pathogenicity of EIEC, we have analyzed the keratoconjunctivitis developed in guinea-pigs with EIEC or S. flexneri.