Paracoccidioides brasiliensis infection increases regulatory T cell counts in female C57BL/6 mice infected via two distinct routes.

Studies that show an overview of the peripheral immune response in a model of Paracoccidioides brasiliensis (Pb) infection in females are scarce in the literature. We sought to characterize the innate and adaptive immune responses in female C57BL/6 mice infected with Pb through two distinct routes of administration, intranasal and intravenous. In addition to the lung, P. brasiliensis yeast cells were observed in liver and brain tissues of females infected intravenously. To our knowledge, our study is the first to prove the presence of this pathogenic fungus in the cerebral cortex of female mice. During the initial stages of infection, augmented expression of both MHCII and CD86 was observed on the surface of CD11c+ pulmonary antigen-presenting cells (APCs) in intranasally and intravenously infected females. However, CD40 expression was downregulated in these cells. Concomitantly with increasing serum IL-10 levels, we noted that splenic dendritic cells (DCs) from both intravenously- and intranasally-infected female mice had acquired an immature phenotype. Further, increased T regulatory cell counts were observed in female mice infected via both routes, along with an increase in the infiltration of IL-10-producing CD8+ T cells into the lungs. Moreover, we noted that P. brasiliensis infection resulted in enhanced IL-10 production - by CD11c+ APCs in the lung tissue - and induction of Th17 polarization. Taken together, our results suggest that P. brasiliensis could modulates the immune response in female mice by influencing the balance between regulatory T cells (Tregs) and Th17 polarization.

Photodynamic inactivation of Paracoccidioides brasiliensis helps the outcome of oral paracoccidiodomycosis.

The antifungal drug therapy often employed to treat paracoccidiodomycosis (PCM), an important neglected fungal systemic infection, leads to offensive adverse effects, besides being very long-lasting. In addition, PCM compromises the oral health of patients by leading to oral lesions that are very painful and disabling. In that way, photodynamic therapy (PDT) arises as a new promising adjuvant treatment for inactivating Paracoccidioides brasiliensis (Pb), the responsible fungus for PCM, and also for helping the patients to deal with such debilitating oral lesions. PDT has been linked to an improved microbial killing, also presenting the advantage of not inducing immediate microbial resistance such as drugs. For the present study, we investigated the generation of reactive oxygen species (ROS) by using the fluorescent probes hydroxyphenyl fluorescein (HPF) and aminophenyl fluorescein (APF) after toluidine blue (TBO-37.5 mg/L)-mediated PDT (660 nm, 40 mW, and 0.04 cm2 spot area) and the action of TBO-PDT upon Pb cultures grown for 7 or 15 days in semisolid Fava Netto's culture medium; we also targeted oral PCM manifestations by reporting the first clinical cases (three patients) to receive topic PDT for such purpose. We were able to show a significant generation of hydroxyl radicals and hypochlorite after TBO-PDT with doses around 90 J/cm2; such ROS generation was particularly useful to attack and inactivate Pb colonies at 7 and 15 days. All three patients reported herein related an immediate relief when it came to pain, mouth opening, and also the ability to chew and swallow. As extracted from our clinical results, which are in fact based on in vitro outcomes, TBO-PDT is a very safe, inexpensive, and promising therapy for the oral manifestations of PCM.

Low-level laser therapy to the mouse femur enhances the fungicidal response of neutrophils against Paracoccidioides brasiliensis.

Neutrophils (PMN) play a central role in host defense against the neglected fungal infection paracoccidioidomycosis (PCM), which is caused by the dimorphic fungus Paracoccidioides brasiliensis (Pb). PCM is of major importance, especially in Latin America, and its treatment relies on the use of antifungal drugs. However, the course of treatment is lengthy, leading to side effects and even development of fungal resistance. The goal of the study was to use low-level laser therapy (LLLT) to stimulate PMN to fight Pb in vivo. Swiss mice with subcutaneous air pouches were inoculated with a virulent strain of Pb or fungal cell wall components (Zymosan), and then received LLLT (780 nm; 50 mW; 12.5 J/cm2; 30 seconds per point, giving a total energy of 0.5 J per point) on alternate days at two points on each hind leg. The aim was to reach the bone marrow in the femur with light. Non-irradiated animals were used as controls. The number and viability of the PMN that migrated to the inoculation site was assessed, as well as their ability to synthesize proteins, produce reactive oxygen species (ROS) and their fungicidal activity. The highly pure PMN populations obtained after 10 days of infection were also subsequently cultured in the presence of Pb for trials of protein production, evaluation of mitochondrial activity, ROS production and quantification of viable fungi growth. PMN from mice that received LLLT were more active metabolically, had higher fungicidal activity against Pb in vivo and also in vitro. The kinetics of neutrophil protein production also correlated with a more activated state. LLLT may be a safe and non-invasive approach to deal with PCM infection.

Imunoterapia ativa especifica no tratamento do carcinoma renal estadio IV: reaçoes linfoproliferativa determinadas por um antigeno purificado da vacina / Specific active immunotherapy foe renal carcinoma stage IV: lymphooproliferitive reactions determined from a purified antigen

Proteinas associadas ao tecido tumoral (PATT) foram extraidas e utilizadas tanto para a preparaçao de uma vacina como para a comparaçao, quanto ao seu perfil imunoquimico com proteinas associadas ao tecido renal normal (PATN). A analise eletroforetica em gel de poliacrilamida na presença de SDS demonstrou a existencia de um componente na fraçao PATT praticamente ausente em PATN. A cromatografia de filtraçao em Sephadex G-100 da fraçao PATT evidenciou seis fraçoes (F1 a F6). A analise eletroforetica das fraçoes obtidas em gel de poliacrimida na presença de SDS, evidenciou que a fraçao F2 encontrada em PATT estava em PATN, sugerindo que a imunogenicidade da vacina em estudo poderia ser atribuida ao antigeno F2. A reaçao linfoproliferativa de celulas do paciente imunizado com a vacina bruta frente a F2 foi cinco vezes maior do que em celulas de individuos normais. A determinaçao de TNF (Fator de Necrose Tumoral) foi realizada no paciente, antes e depois do inicio da imunoterapia, e mostrou a queda desta citocina em torno de 47//apos seis meses de tratamento com a vacina.