Marcos Vinicius da Silva

IL-17-expressing CD4⁺ and CD8⁺ T lymphocytes in human toxoplasmosis.

This study aimed to measure the synthesis of Th1 and Th2 cytokines by mononuclear cells after culture with live T. gondii and identified Th17 (CD4+) and Tc17 (CD8+) cells in toxoplasma-seronegative and toxoplasma-seropositive parturient and nonpregnant women. Cytometric bead arrays were used to measure cytokine levels (IL-2, TNF-α, IFN-γ, IL-4, IL-5, and IL-10); immunophenotyping was used to characterize Th17 and Tc17 cells, and the cells were stained with antibodies against CD4+ and CD8+ T cells expressing IL-17. The addition of tachyzoites to cell cultures induced the synthesis of IL-5, IL-10, and TNF-α by cells from seronegative parturient women and of IL-5 and IL-10 by cells from seropositive, nonpregnant women. We observed a lower level of IL-17-expressing CD4+ and CD8+ T lymphocytes in cultures of cells from seronegative and seropositive parturient and nonpregnant women that were stimulated with tachyzoites, whereas analysis of the CD4+ and CD8+ T cell populations showed a higher level of CD4+ T cells compared with CD8+ T cells. These results suggest that the cytokine pattern and IL-17-expressing CD4+ and CD8+ T lymphocytes may have important roles in the inflammatory response to T. gondii, thus contributing to the maintenance of pregnancy and control of parasite invasion and replication.

Priming Mesenchymal Stem Cells with Endothelial Growth Medium Boosts Stem Cell Therapy for Systemic Arterial Hypertension.

Systemic arterial hypertension (SAH), a clinical syndrome characterized by persistent elevation of arterial pressure, is often associated with abnormalities such as microvascular rarefaction, defective angiogenesis, and endothelial dysfunction. Mesenchymal stem cells (MSCs), which normally induce angiogenesis and improve endothelial function, are defective in SAH. The central aim of this study was to evaluate whether priming of MSCs with endothelial growth medium (EGM-2) increases their therapeutic effects in spontaneously hypertensive rats (SHRs). Adult female SHRs were administered an intraperitoneal injection of vehicle solution (n = 10), MSCs cultured in conventional medium (DMEM plus 10% FBS, n = 11), or MSCs cultured in conventional medium followed by 72 hours in EGM-2 (pMSC, n = 10). Priming of the MSCs reduced the basal cell death rate in vitro. The administration of pMSCs significantly induced a prolonged reduction (10 days) in arterial pressure, a decrease in cardiac hypertrophy, an improvement in endothelium-dependent vasodilation response to acetylcholine, and an increase in skeletal muscle microvascular density compared to the vehicle and MSC groups. The transplanted cells were rarely found in the hearts and kidneys. Taken together, our findings indicate that priming of MSCs boosts stem cell therapy for the treatment of SAH.

Th1/Th17-Related Cytokines and Chemokines and Their Implications in the Pathogenesis of Pemphigus Vulgaris

Pemphigus vulgaris (PV) is an autoimmune disease characterized by the presence of IgG autoantibodies against desmoglein-3. Despite the variety of findings, the chemokine and cytokine profiles that characterize the immune response in the disease are still poorly explored. Thus, 20 PV patients and 20 controls were grouped according to gender, ethnicity, place of residence, and clinical parameters of the disease. Then, the levels of chemokines and of Th1/Th2/Th17/Treg/Th9/Th22-related cytokines were assessed in the serum. PV patients had higher levels of inflammatory Th1/Th17 cytokines (IFN-γ, IL-17, and IL-23), as well as higher levels of CXCL8 and reduced levels of Th1/Th2-related chemokines (IP-10 and CCL11). However, no differences in the levels of IL-2, IL-6, TNF-α, IL-1β, IL-4, IL-9, IL-12, TGF-β, IL-33, MCP-1, RANTES, and MIP-1α were found between PV patients and their control counterparts. Furthermore, PV patients with skin lesions had higher serum levels of IL-6 and CXCL8 when compared to PV patients without lesions. Taken together, our findings describe the role of cytokines and chemokines associated with Th1/Th17 immune response in PV patients. Finally, these data are important for better understanding of the immune aspects that control disease outcome, and they may also provide important information about why patients develop autoantibodies against desmogleins.

Morinda citrifolia (Noni) Fruit Juice Reduces Inflammatory Cytokines Expression and Contributes to the Maintenance of Intestinal Mucosal Integrity in DSS Experimental Colitis

Morinda citrifolia L. (noni) has been shown to treat different disorders. However, data concerning its role in the treatment of intestinal inflammation still require clarification. In the current study, we investigated the effects of noni fruit juice (NFJ) in the treatment of C57BL/6 mice, which were continuously exposed to dextran sulfate sodium (DSS) for 9 consecutive days. NFJ consumption had no impact on the reduction of the clinical signs of the disease or on weight loss. Nonetheless, when a dilution of 1 : 10 was used, the intestinal architecture of the mice was preserved, accompanied by a reduction in the inflammatory infiltrate. Regardless of the concentration of NFJ, a decrease in both the activity of myeloperoxidase and the key inflammatory cytokines, TNF-α and IFN-γ, was also observed in the intestine. Furthermore, when NFJ was diluted 1 : 10 and 1 : 100, a reduction in the production of nitric oxide and IL-17 was detected in gut homogenates. Overall, the treatment with NFJ was effective in different aspects associated with disease progression and worsening. These results may point to noni fruit as an important source of anti-inflammatory molecules with a great potential to inhibit the progression of inflammatory diseases, such as inflammatory bowel disease.

In Situ Cytokine Expression and Morphometric Evaluation of Total Collagen and Collagens Type I and Type III in Keloid Scars

Keloids are characterized by excessive collagen deposition and growth beyond the edges of the initial injury, and cytokines may be related to their formation. The objective of this study was to evaluate the collagen fibers, analyze in situ expression of cytokines in keloid lesions, and compare to the control group. Results showed that there was a predominance of women and nonwhite and direct black ancestry. Keloid showed a significant increase in total and type III collagen. Significantly, the expression of mRNA for TGF-β in keloid was increased, the expressions of IFN-γ, IFN-γR1, and IL-10 were lower, and IFN-γR1 and TNF-α had no statistical difference. Correlations between collagen type III and TGF-β mRNA expression were positive and significant, IFN-γ, IFN-γR1, and IL-10 were negative and significant, and TNF-α showed no statistical difference. We conclude that there was a significant increase of total collagen in keloid and predominance of collagen type III compared to the controls, showing keloid as an immature lesion. There is a significant increase in TGF-β mRNA in keloid lesions, and a significant decrease in IFN-γ and IL-10, suggesting that these cytokines are related to keloid lesions.

Effect of the saliva from different triatomine species on the biology and immunity of TLR-4 ligand and Trypanosoma cruzi-stimulated dendritic cells

BackgroundTriatomines are blood-sucking vectors of Trypanosoma cruzi, the causative agent of Chagas disease. During feeding, triatomines surpass the skin host response through biomolecules present in their saliva. Dendritic cells (DCs) play a crucial role in the induction of the protection to aggressive agents, including blood-sucking arthropods. Here, we evaluated if salivary components of triatomines from different genera evade the host immunity by modulating the biology and the function of LPS- or T. cruzi-stimulated DCs.MethodsSaliva of Panstrongylus lignarius, Meccus pallidipennis, Triatoma lecticularia and Rhodnius prolixus were obtained by dissection of salivary glands and the DCs were obtained from the differentiation of mouse bone marrow precursors.ResultsThe differentiation of DCs was inhibited by saliva of all species tested. Saliva differentially inhibited the expression of MHC-II, CD40, CD80 and CD86 in LPS-matured DCs. Except for the saliva of R. prolixus, which induced IL-6 cytokine production, TNF-α, IL-12 and IL-6 were inhibited by the saliva of the other three tested species and IL-10 was increased in all of them. Saliva per se, also induced the production of IL-12, IL-6 and IL-10. Only the saliva of R. prolixus induced DCs apoptosis. The presence of PGE2 was not detected in the saliva of the four triatomines studied. Finally, T. cruzi invasion on DCs is enhanced by the presence of the triatomine saliva.ConclusionsThese results demonstrate that saliva from different triatomine species exhibit immunomodulatory effects on LPS and T. cruzi-stimulated DCs. These effects could be related to hematophagy and transmission of T. cruzi during feeding.

DNA content analysis allows discrimination between Trypanosoma cruzi and Trypanosoma rangeli

Trypanosoma cruzi, a human protozoan parasite, is the causative agent of Chagas disease. Currently the species is divided into six taxonomic groups. The genome of the CL Brener clone has been estimated to be 106.4–110.7 Mb, and DNA content analyses revealed that it is a diploid hybrid clone. Trypanosoma rangeli is a hemoflagellate that has the same reservoirs and vectors as T. cruzi; however, it is non-pathogenic to vertebrate hosts. The haploid genome of T. rangeli was previously estimated to be 24 Mb. The parasitic strains of T. rangeli are divided into KP1(+) and KP1(−). Thus, the objective of this study was to investigate the DNA content in different strains of T. cruzi and T. rangeli by flow cytometry. All T. cruzi and T. rangeli strains yielded cell cycle profiles with clearly identifiable G1-0 (2n) and G2-M (4n) peaks. T. cruzi and T. rangeli genome sizes were estimated using the clone CL Brener and the Leishmania major CC1 as reference cell lines because their genome sequences have been previously determined. The DNA content of T. cruzi strains ranged from 87,41 to 108,16 Mb, and the DNA content of T. rangeli strains ranged from 63,25 Mb to 68,66 Mb. No differences in DNA content were observed between KP1(+) and KP1(−) T. rangeli strains. Cultures containing mixtures of the epimastigote forms of T. cruzi and T. rangeli strains resulted in cell cycle profiles with distinct G1 peaks for strains of each species. These results demonstrate that DNA content analysis by flow cytometry is a reliable technique for discrimination between T. cruzi and T. rangeli isolated from different hosts.

Salivary Gland Extract of Kissing Bug, Triatoma lecticularia, Reduces the Severity of Intestinal Inflammation through the Modulation of the Local IL-6/IL-10 Axis

Triatomines are known for their role as vectors of the causative agent of Chagas disease. The occurrence of an arsenal of molecules in their saliva is able to suppress vertebrate immune responses. Thus, it is reasonable to assume that the presence of molecules with therapeutic potential in their saliva is able to constrain inflammation in immune-mediated diseases. Thus, mice were exposed to dextran sulfate sodium (DSS) in drinking water uninterruptedly during 6 consecutive days and treated with T. lecticularia salivary gland extract (SGE) (3, 10, or 30 μg) or vehicle (saline) (n = 6/group). At the highest dose (30 μg), an improvement in clinical outcome and macroscopic aspects of the intestine were observed. This observation was followed by amelioration in histopathological aspects in the colon especially when the doses of 10 and 30 μg were used. Regardless of the concentration used, treatment with T. lecticularia SGE significantly reduced the levels of the inflammatory cytokine IL-6 in the intestine. The production of the anti-inflammatory cytokine IL-10 was positively impacted by the concentrations of 3 and 30 μg. Our results suggest that the presence of molecules in the T. lecticularia SGE is able to attenuate clinical outcome and colon shortening and improve intestinal architecture besides reducing the production of IL-6 and inducing a local production of IL-10 in the intestine.

Evaluation of the cytotoxic response mediated by perforin and granzyme B in patients with non-Hodgkin lymphoma

Abstract This study quantified the perforin and granzyme B in patients with non-Hodgkin lymphoma (NHL) at the time of diagnosis. Protein quantification was performed by flow cytometry. NHL patients had a higher number of cytotoxic T lymphocytes (CTLs) expressing perforin as well as a greater number of activated CTLs than the control group. However, intracellular perforin levels in natural killer cells were lower in the NHL patients compared to the control group. Quantitative real time PCR showed that patients had more expression of perforin and granzyme B transcripts compared to the control group. In addition, patients who had expression of both genes below the median found for the NHL group had lower survival rates. Considering this, we believe that perforin and granzyme B are potential prognostic markers in NHL and thus it is fundamental to pay attention to their expressions in these patients.

High in situ mRNA levels of IL-22, TFG-β, and ARG-1 in keloid scars

Keloid scars are currently considered a chronic inflammatory process and no longer a benign skin tumor. Keloids are defined as highly inflamed, hyperproliferative pathological scars. Growth factors and cytokines have important functions in the keloid inflammatory etiopathogenesis. The aim of this study was to analyze the in situ expression of cytokines and growth factors in keloid scars in comparison with that in normal scars. Among them, we specifically assessed TGF-β, FGF, IL-33, IL-22, ARG-1, ARG-2, iNOS, VIP, VIP-R1, TAC, and TAC-R1. A total of 98 biopsies were evaluated, including of 53 keloid and 45 normal scars. The age of patients with keloids ranged from 11 to 73 years, with a mean age of 28 years and predominance of the female gender (58.5% of the total patients). Around 64.15% of the patients belonged to the black ethnic group. Evaluated keloids were most commonly located in the earlobe because of ear piercing, representing 73.6% of the cases. We found significantly greater expression of TGF-β, IL-22, and ARG-1 in keloids when compared with that in normal scars. As for IL-33, ARG-2, and VIP-R1, despite the higher number of mRNA copies found in keloids, this difference was not significant. Furthermore, FGF, iNOS, VIP, TAC, and TAC-R1 mRNA levels were not detectable, and therefore these results were inconclusive in this study. Considering these results, understanding the cellular and molecular mechanisms that control the inflammatory response during cutaneous healing may promote the development of strategies to improve the treatment of patients with keloids.