Evaluation of CD8+ T cell subpopulations in paracoccidioidomycosis.

Aim: We aimed to verify the frequency of CD8+ T cell subsets in patients with acute form and chronic form of paracoccidioidomycosis. Material & Methods: Mononuclear cells from paracoccidioidomycosis patients and healthy donors were isolated and phenotyped by flow cytometry. Dendritic cells were pulsed with Paracoccidioides brasiliensis yeast and co-cultures with lymphocytes. Cytokine production was measured by ELISA. Results: Acute form patients present a higher frequency of Tc1 and Tc10 cells, while chronic form patients have more Tc1 and Tc21 cells, compared with healthy controls. In vitro assays showed that P. brasiliensis induced polarization to the Tc17/Tc22 subsets. Conclusion: Our results suggest that CD8+ T cells can respond in a similar way to P. brasiliensis infection, regardless of the clinical presentation of the disease.

Near-fatal poisoning after ricin injection.

OBJECTIVE: To report a near-fatal poisoning after intentional injection of ricin from a castor bean (Ricinus communis) extract. CASE REPORT: A 21 year-old man self-injected ∼3 mL of a castor bean extract intramuscularly and subcutaneously in the left antecubital fossa. Upon admission to our ED (1 h post-exposure; day 1, D1) he was awake and alert, but complained of mild local pain and showed slight local edema and erythema. He evolved to refractory shock (∼24 h post-exposure) that required the administration of a large volume of fluids and high doses of norepinephrine and vasopressin, mainly from D2 to D4. During this period, he developed clinical and laboratory features compatible with systemic inflammatory response syndrome, multiple organ dysfunction, capillary leak syndrome, rhabdomyolysis, necrotizing fasciitis and possible compartment syndrome. The patient underwent forearm fasciotomy on D4 and there was progressive improvement of the hemodynamic status from D7 onwards. Wound management involved several debridements, broad-spectrum antibiotics and two skin grafts. Major laboratory findings within 12 days post-exposure revealed hypoalbuminemia, proteinuria, thrombocytopenia, leukocytosis and increases in cytokines (IL-6, IL-10 and TNF-α), troponin and creatine kinase. Ricin A-chain (ELISA) was detected in serum up to D3 (peak at 24 h post-exposure), with ∼79% being excreted in the urine within 64 h post-exposure. Ricinine was detected in serum and urine by LC-MS up to D5. A ricin A-chain concentration of 246 µg/mL was found in the seed extract, corresponding to the injection of ∼738 µg of ricin A-chain (∼10.5 µg/kg). The patient was discharged on D71, with limited range of motion and function of the left forearm and hand. CONCLUSION: Ricin injection resulted in a near-fatal poisoning that evolved with septic shock-like syndrome, multiple organ dysfunction and necrotizing fasciitis, all of which were successfully treated with supportive care.

1,2,3,4,6-Penta-O-galloyl-ß-d-glucose modulates perivascular inflammation and prevents vascular dysfunction in angiotensin II-induced hypertension.

BACKGROUND AND PURPOSE: Hypertension is a multifactorial disease, manifested by vascular dysfunction, increased superoxide production, and perivascular inflammation. In this study, we have hypothesized that 1,2,3,4,6-penta-O-galloyl-ß-d-glucose (PGG) would inhibit vascular inflammation and protect from vascular dysfunction in an experimental model of hypertension. EXPERIMENTAL APPROACH: PGG was administered to mice every 2 days at a dose of 10 mg·kg-1 i.p during 14 days of Ang II infusion. It was used at a final concentration of 20 µM for in vitro studies in cultured cells. KEY RESULTS: Ang II administration increased leukocyte and T-cell content in perivascular adipose tissue (pVAT), and administration of PGG significantly decreased total leukocyte and T-cell infiltration in pVAT. This effect was observed in relation to all T-cell subsets. PGG also decreased the content of T-cells bearing CD25, CCR5, and CD44 receptors and the expression of both monocyte chemoattractant protein 1 (CCL2) in aorta and RANTES (CCL5) in pVAT. PGG administration decreased the content of TNF+ and IFN-γ+ CD8 T-cells and IL-17A+ CD4+ and CD3+ CD4- CD8- cells. Importantly, these effects of PGG were associated with improved vascular function and decreased ROS production in the aortas of Ang II-infused animals independently of the BP increase. Mechanistically, PGG (20 µM) directly inhibited CD25 and CCR5 expression in cultured T-cells. It also decreased the content of IFN-γ+ CD8+ and CD3+ CD4- CD8- cells and IL-17A+ CD3+ CD4- CD8- cells. CONCLUSION AND IMPLICATION: PGG may constitute an interesting immunomodulating strategy in the regulation of vascular dysfunction and hypertension. LINKED ARTICLES: This article is part of a themed section on Immune Targets in Hypertension. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v176.12/issuetoc.

Effect of ArtinM on Human Blood Cells During Infection With Paracoccidioides brasiliensis.

Infections caused by fungi are prominent in our environment and can be potentially fatal. paracoccidioidomycosis (PCM), caused by fungi of the Paracoccidioides genus, is the most frequent systemic mycosis in Brazil and the main cause of death among immunocompetent individuals. The antifungal therapy for PCM is usually effective but side effects and relapses are often reported. The latter could be avoided with alternative or complementary therapies aimed at boosting the immune response to combat this pathogen. Recent reports have pointed at the importance of an effective cellular immune response, with the participation of Th1 cells, in the resistance to and control of Paracoccidioides infection. The ArtinM lectin, extracted from jackfruit (Artocarpus heterophyllus) seeds, exhibits immunomodulatory activity against several intracellular pathogens, including Paracoccidioides brasiliensis, by promoting the development of a Th1 immune response. The aim of this work was to characterize the effect of ArtinM on peripheral blood cells of patients with PCM and on those of control individuals infected with fungal yeasts cells in vitro. Our results demonstrate that ArtinM activates human neutrophils in vitro, leading to an increase in cytokine production and CD54 expression. ArtinM activated P. brasiliensis-infected neutrophils from both healthy individuals and patients with PCM. This activation was not dependent on the dectin-1 receptor, because pre-incubation with laminarin, a dectin-1 receptor blocker, did not reverse the activated state of the cells. ArtinM also stimulated human peripheral blood mononuclear cells to secrete pro-inflammatory Th1-related cytokines, which are protective against Paracoccidioides infection. These data support the immunostimulatory action of ArtinM and encourage new studies using the lectin for the immunotherapy of PCM.