Estimated quantification of residual volume in vaccines supplies and its impact on the Brazilian health system.

Between 2017 and 2021, the Brazilian Unified Health System (BUHS) administered a total of 527,903,302 doses of immunizations. Each immunization results in the presence of a residual volume (RV) due to syringe dead space (DS). The International Organization for Standardization 7886-1 allows a DS of up to 0.07mL in sterile single-use hypodermic syringes with volumes less than 5mL. This study aims to quantify the DS of immunization devices used in Brazil, study the best combinations of needles and syringes to minimize RV, estimate the number of wasted doses from 2017 to 2021, and evaluate the impact on the BUHS. Pneumococcal 10 vaccine with a 25x6mm needle and a regular 1mL syringe exhibited a significantly higher average RV (0.0826mL) and waste rate (14.42%). It was observed that for some intramuscular vaccines, there is less waste when using a 20x5.5mm needle compared to a 25x6mm needle. The use of syringes with plunger stoppers that penetrate the syringe barrel, denoted as low dead space syringes, results in less RV and an estimated difference in the waste rate of approximately 10% compared to the regular syringe. The estimated number of wasted doses from 2017 to 2021 by BUHS is approximately 32 million doses.

Exploring the functionalization of Ti-6Al-4V alloy with the novel antimicrobial peptide JIChis-2 via plasma polymerization.

This study aimed to characterize the immobilization of the novel JIChis-2 peptide on the Ti-6Al-4V alloy, widely used in the biomedical sector. The antimicrobial activity of JIChis-2 was evaluated in the Gram-negative bacterium E. coli. Its immobilization occurred by inducing the formation of covalent bonds between the N-terminus of the peptides and the surface previously submitted to acrylic acid polymerization via the PECVD technique. Coated and uncoated surfaces were characterized by FTIR, AFM, SEM and EDX. Studies of global and localized corrosion were carried out, seeking to explore the effects triggered by surface treatment in an aggressive environment. Additionally, the ability of the functionalized material to prevent E. coli biofilm formation evidenced that the strategy to immobilize JIChis-2 in the Ti-6Al-4V alloy via PECVD of acrylic acid resulted in the development of a functional material with antibiofilm properties.

Congenital transmission of Mexican strains of Trypanosoma cruzi TcIa: interaction between parasite and human placental explants.

Congenital transmission of Chagas disease plays an important role in endemic countries because it is not a diagnosis that is encountered frequently in prenatal care. Due to limited information regarding congenital transmission of Trypanosoma cruzi in Mexico, the present study aimed to investigate protozoan infectivity and modulation of immune responses in human placental explants infected with T. cruzi Ia Mexican strains. The Inc-5 strain showed increased infectivity and modulated IL-1ß, IL-10 and TLR-4, decreasing their expression after 24 h of infection. Both strains (Inc-5 and Ninoa) stimulated the production of TNF-α and decreased IL-6 levels 96 h after infection. An important detachment of the syncytiotrophoblast caused by infection with T. cruzi was observed after 24 h of infection. In this study, ex vivo infection of human placental villi was performed to better understand interactions involving parasitic T. cruzi and human placental tissue. It was concluded that the strains of TcIa present parasitism in placental tissue, modulation of the innate immune system of the placenta, and cause intense detachment of the syncytiotrophoblast, a fact that may be more associated with abortion and premature birth events than the congenital transmission itself, justifying the low rate of this transmission mechanism by this genotype.

New insights of Nb2O5-based coatings on the 316L SS surfaces: enhanced biological responses.

This communication aims to propose new insights of Nb2O5-based coatings on the 316L SS surface with great prospects to be used in the dentistry field as brackets. The Nb2O5 thin film was incorporated into the 316L SS by using PVD method. For this purpose, the studied system was characterized structurally and morphologically by using AFM, FTIR-IRRAS, Raman spectroscopy and X-ray photoelectron spectroscopy (XPS). Biological assays were performed using human gingival fibroblast cell-line HGF-1. In agreement with FTIR and Raman results, the XPS technique indicates that Nb is present in an oxidation state assigned to Nb2O5. Furthermore, the coatings produced by PVD technique are less toxic and induces less inflammation in gingival cells (cell-line HGF-1), suggesting the strategy of use Nb2O5 thin film to cover the 316L SS promoted since its protection of the physiological environment to its biocompatibility improvement.

The pan-genome of Treponema pallidum reveals differences in genome plasticity between subspecies related to venereal and non-venereal syphilis.

BACKGROUND: Spirochetal organisms of the Treponema genus are responsible for causing Treponematoses. Pathogenic treponemes is a Gram-negative, motile, spirochete pathogen that causes syphilis in human. Treponema pallidum subsp. endemicum (TEN) causes endemic syphilis (bejel); T. pallidum subsp. pallidum (TPA) causes venereal syphilis; T. pallidum subsp. pertenue (TPE) causes yaws; and T. pallidum subsp. Ccarateum causes pinta. Out of these four high morbidity diseases, venereal syphilis is mediated by sexual contact; the other three diseases are transmitted by close personal contact. The global distribution of syphilis is alarming and there is an increasing need of proper treatment and preventive measures. Unfortunately, effective measures are limited. RESULTS: Here, the genome sequences of 53 T. pallidum strains isolated from different parts of the world and a diverse range of hosts were comparatively analysed using pan-genomic strategy. Phylogenomic, pan-genomic, core genomic and singleton analysis disclosed the close connection among all strains of the pathogen T. pallidum, its clonal behaviour and showed increases in the sizes of the pan-genome. Based on the genome plasticity analysis of the subsets containing the subspecies T pallidum subsp. pallidum, T. pallidum subsp. endemicum and T. pallidum subsp. pertenue, we found differences in the presence/absence of pathogenicity islands (PAIs) and genomic islands (GIs) on subsp.-based study. CONCLUSIONS: In summary, we identified four pathogenicity islands (PAIs), eight genomic islands (GIs) in subsp. pallidum, whereas subsp. endemicum has three PAIs and seven GIs and subsp. pertenue harbours three PAIs and eight GIs. Concerning the presence of genes in PAIs and GIs, we found some genes related to lipid and amino acid biosynthesis that were only present in the subsp. of T. pallidum, compared to T. pallidum subsp. endemicum and T. pallidum subsp. pertenue.

Macrophage migration inhibitory factor (MIF) and pregnancy may impact the balance of intestinal cytokines and the development of intestinal pathology caused by Toxoplasma gondii infection.

Toxoplasma gondii (T. gondii) is an intracellular parasite responsible for causing toxoplasmosis. When infection occurs during pregnancy, it can produce severe congenital infection with ocular and neurologic damage to the infant. From the oral infection parasite reaches the intestine, causing inflammatory response, damage in tissue architecture and systemic dissemination. Macrophage migration inhibition factor (MIF) is a cytokine secreted from both immune and non-immune cells, including gut epithelial cells. MIF is described to promote inflammatory responses, to be associated in colitis pathogenesis and also to play role in maintaining the intestinal barrier. The aim of the present study was to evaluate the influence of the pregnancy and MIF deficiency on T. gondii infection in the intestinal microenvironment and to address how these factors can impact on the intestinal architecture and local cytokine profile. For this purpose, small intestine of pregnant and non-pregnant C57BL/6 MIF deficient mice (MIF-/-) and Wild-type (WT) orally infected with 5 cysts of ME-49 strain of T. gondii were collected on day 8th of infection. Intestines were processed for morphological and morphometric analyses, parasite quantification and for cytokines mensuration. Our results showed that the absence of MIF and pregnancy caused an increase in T. gondii infection index. T. gondii immunolocalization demonstrated that segments preferentially infected with T. gondii were duodenum and ileum. The infection caused a reduction in the size of the intestinal villi, whereas, infection associated with pregnancy caused an increase in villi size due to edema caused by the infection. Also, the goblet cell number was increased in the ileum of MIF-/- mice, when compared to the corresponding WT group. Analyses of cytokine production in the small intestine showed that MIF was up regulated in the gut of pregnant WT mice due to infection. Also, infection provoked an intense Th1 response that was more exacerbated in pregnant MIF-/- mice. We also detected that the Th2/Treg response was more pronounced in MIF-/- mice. Altogether, our results demonstrated that pregnancy and MIF deficiency interferes in the balance of the intestinal cytokines and favors a Th1-immflamatory profile, which in turn, impact in the development of pathology caused by T. gondii infection in the intestinal microenvironment.

T-Cell Immunophenotyping and Cytokine Production Analysis in Patients with Chagas Disease 4 Years after Benznidazole Treatment.

The major problem with Chagas disease is evolution of the chronic indeterminate form to a progressive cardiac disease. Treatment diminishes parasitemia but not clinical progression, and the immunological features involved are unclear. Here, we studied the clinical course and the immune response in patients with chronic-phase Chagas disease at 48 months after benznidazole treatment. Progression to the cardiac form of Chagas disease or its aggravation was associated with higher in vitro antigen-specific production of interferon gamma (IFN-γ) in patients with cardiac Chagas disease than in patients with the indeterminate form. Predominance of IFN-γ production over interleukin-10 (IL-10) production in antigen-specific cultures was associated with cardiac involvement. Significantly higher numbers of antigen-specific T helper 1 cells (T-Bet+ IFN-γ+) and a significantly higher IFN-γ+/IL-10+ ratio were observed in patients with cardiac Chagas disease than in patients with the indeterminate form. Cardiac damage was associated with higher numbers of T helper cells than cytotoxic T lymphocytes producing IFN-γ. Patients with cardiac Chagas disease had predominant CD25- and CD25low T regulatory (Treg) subpopulations, whereas patients with the indeterminate form manifested a higher relative mean percentage of CD25high Treg subpopulations. These findings suggest that at 48 months after benznidazole treatment, the disease can worsen or progress to the cardiac form. The progression may be related to increased IFN-γ production (mostly from CD4+ T cells) relative to IL-10 production and increased Treg percentages. Patients with the indeterminate form of Chagas disease show a more balanced ratio of proinflammatory and anti-inflammatory cytokines.

An introduction of the role of probiotics in human infections and autoimmune diseases.

During the last decades, studies exploring the role of microorganisms inhabiting human body in different scenarios have demonstrated the great potential of modulating them to treat and prevent diseases. Among the most outstanding applications, probiotics have been used for over a century to treat infections and inflammation. Despite the beneficial role of other probiotics, Lactobacillus and Bifidobacterium species are the most frequently used, and have been effective as a therapeutic option in the treatment/prevention of dental caries, periodontal diseases, urogenital infections, and gastrointestinal infections. Additionally, as gastrointestinal tract harbors a great diversity of microbial species that directly or indirectly modulate host metabolism and immune response, the influence of intestinal microbiota, one of the targets of therapies using probiotics, on the biology of immune cells can be explored to treat inflammatory disorders or immune-mediated diseases. Thus, it is not surprising that probiotics have presented promising results in modulating human inflammatory diseases such as type 1 diabetes, multiple sclerosis, rheumatoid arthritis and inflammatory bowel disease, among others. Hence, the purpose of this review is to discuss the potential of therapeutic approaches using probiotics to constrain infection and development of inflammation on human subjects.

Treatment with a Zinc Metalloprotease Purified from Bothrops moojeni Snake Venom (BmooMP-Alpha-I) Reduces the Inflammation in an Experimental Model of Dextran Sulfate Sodium-Induced Colitis.

It has been described that the metalloprotease BmooMP-alpha-I purified from Bothrops moojeni snake venom is able to hydrolyze the TNF molecule. However, this observation has been based mainly on in vitro investigation, in addition to molecular modeling and docking approaches. Considering that there is no in vivo study to demonstrate the biological effects of this enzyme, the major aim to the present work was to investigate whether the BmooMP-alpha-I has any anti-inflammatory efficacy by setting up a murine experimental design of colitis induced by dextran sulfate sodium (DSS). For this purpose, C57BL/6 mice were divided into six groups, as follows: (i) animals without intestinal inflammation, (ii) animals without intestinal inflammation treated with BmooMP-alpha-I (50 µg/animal/day), and (iii) animals with intestinal inflammation induced by 3% of DSS, (iv) mice with intestinal inflammation induced by DSS and treated with BmooMP-alpha-I enzyme at the 50, 25, or 12.5 µg/animal/day dosages by intraperitoneal route. Clinical signs of colitis were observed daily for calculating the morbidity scores, cytokine measurements, and histological features. We observed that the animals treated with different doses of the enzyme presented a remarkable improvement of colitis signs, as confirmed by a significant increase of the intestine length in comparison to the DSS group. Also, no difference was observed between the groups treated with the enzyme or vehicle, as the colon length of these animals was slightly lower than that of the group of healthy animals, without induction of intestinal inflammation. The cytokine quantification in supernatants of intestinal tissue homogenates showed a significant reduction of 38% in IFN-gamma levels, when the animals were treated with 50 µg of the BmooMP-alpha-I compared to the animals receiving DSS only. A significant reduction of 39% in TNF levels was also observed in all doses of treatment with BmooMP-alpha-I, in addition to a significant reduction of 35% in the amount of IL-12p40. Histological examinations revealed that the BmooMP-alpha-I 50 µg treated group preserved colon architecture and goblet cells and reduced the ulcer area, when compared with DSS mice, which showed typical inflammatory changes in tissue architecture, such as ulceration, crypt dilation, loss of tissue architecture, and goblet cell depletion, accompanied by a significant cell infiltration. In conclusion, our results suggest that the improvement of clinical scores and histological findings related to BmooMP-alpha-I treatment in this experimental model could be attributed to the metalloprotease ability to modulate cytokine production locally at the inflamed intestine. These findings highlight the potential anti-inflammatory role and effectiveness of this enzyme as a therapeutic alternative in this type of immunopathological condition.

Trypanosoma cruzi Mexican Strains Differentially Modulate Surface Markers and Cytokine Production in Bone Marrow-Derived Dendritic Cells from C57BL/6 and BALB/c Mice.

Dendritic cells (DCs) are a type of antigen-presenting cells that play an important role in the immune response against Trypanosoma cruzi, the causative agent of Chagas disease. In vitro and in vivo studies have shown that the modulation of these cells by this parasite can directly affect the innate and acquired immune response of the host in order to facilitate its biological cycle and the spreading of the species. Many studies show the mechanisms by which T. cruzi modulates DCs, but the interaction of these cells with the Mexican strains of T. cruzi such as Ninoa and INC5 has not yet been properly investigated. Here, we evaluated whether Ninoa and INC5 strains evaded the immunity of their hosts by modulating the biology and function of murine DCs. The CL-Brener strain was used as the reference strain. Herein, it was demonstrated that Ninoa was more infective toward bone marrow-derived dendritic cells (BMDCs) than INC5 and CL-Brener strains in both BMDCs of BALB/c and C57BL/6 mice. Mexican strains of T. cruzi induced different cytokine patterns. In BMDCs obtained from BALB/c mice, Ninoa strain led to the reduction in IL-6 and increased IL-10 production, while in C57BL/6 mice Ninoa strain considerably increased the productions of TNF-α and IL-10. Also, Ninoa and INC5 differentially modulated BMDC expressions of MHC-II, TLR2, and TLR4 in both BALB/c and C57BL/6 mice compared to Brazilian strain CL-Brener. These results indicate that T. cruzi Mexican strains differentially infect and modulate MHC-II, toll-like receptors, and cytokine production in DCs obtained from C57BL/6 and BALB/c mice, suggesting that these strains have developed particular modulatory strategies to disrupt DCs and, consequently, the host immune responses.

Parasitological and immunological evaluation of cattle experimentally infected with Trypanosoma vivax.

Trypanosoma vivax infection causes relevant economical impact due to high morbidity and mortality leading to negative impact on local livestock. Despite parasitological and serological methods are used for the diagnosis of T. vivax infection, gaps regarding sensitivity and specificity of these methods still represent a challenge. The present study aimed to compare the kinetics of parasitological and serological parameters in cattle experimentally infected with T. vivax along with immunophenotypic analysis of whole blood leukocytes. Based on the parasitemia profile the analysis were performed in three distinct periods, referred as pre-patent, patent and post-treatment. Distinct kinetics of anti-T. vivax IgM and IgG were observed during the pre-patent, patent and post-treatment periods. Increased levels of WC1+ γδ T-cells were observed throughout the infection with strong correlations with other biomarkers observed during post-treatment period. Our findings demonstrated that there is a important participation of Monocytes:CD14+; NK-cells:CD335+ and WC1+ γδ T-cells that coincide with the peak of parasitemia and also with the adaptive immunity, specially CD4+ T-cells in T. vivax infection. The knowledge of the immune response is important not only for understanding the biology of the parasite in the host, but for the design of new treatment strategies for trypanosome infections.

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.

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-1ß, IL-4, IL-9, IL-12, TGF-ß, 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.

Vector species richness predicts local mortality rates from Chagas disease.

Vector species richness may drive the prevalence of vector-borne diseases by influencing pathogen transmission rates. The dilution effect hypothesis predicts that higher biodiversity reduces disease prevalence, but with inconclusive evidence. In contrast, the amplification effect hypothesis suggests that higher vector diversity may result in greater disease transmission by increasing and diversifying the transmission pathways. The relationship between vector diversity and pathogen transmission remains unclear and requires further study. Chagas disease is a vector-borne disease most prevalent in Brazil and transmitted by multiple species of insect vectors of the subfamily Triatominae, yet the drivers of spatial variation in its impact on human populations remain unresolved. We tested whether triatomine species richness, latitude, bioclimatic variables, human host population density, and socioeconomic variables predict Chagas disease mortality rates across over 5000 spatial grid cells covering all of Brazil. Results show that species richness of triatomine vectors is a good predictor of mortality rates caused by Chagas disease, which supports the amplification effect hypothesis. Vector richness and the impact of Chagas disease may also be driven by latitudinal components of climate and human socioeconomic factors. We provide evidence that vector diversity is a strong predictor of disease prevalence and give support to the amplification effect hypothesis.

Maternal deaths caused by eclampsia in Brazil: a descriptive study from 2000 to 2021.

Objective: Eclampsia is a hypertensive disorder that occurs during pregnancy and can lead to death. The literature has gaps by not providing comprehensive data on the epidemiology of the disease, restricting analysis to limited temporal intervals and geographical locations. This study aims to characterize the epidemiological profile of women who died from eclampsia in Brazil from 2000 to 2021. Methods: The maternal mortality data were obtained from the Sistema de Informações sobre Mortalidade, with the following variables of interest selected: "Federative Unit," "Year," "Age Range," "Race/Color," and "Education Level." The collection of the number of live births for data normalization was conducted in the Sistema de Informações sobre Nascidos Vivos. Statistical analyses were performed using GraphPad Prism, calculating odds ratio for variables and fixing number of deaths per 100,000 live births for calculating maternal mortality ratio (MMR). Results: There was a downward trend in maternal mortality rate during the study period. Maranhão stood out as the federative unit with the highest MMR (17 deaths per 100.000 live births). Mothers aged between 40 and 49 years (OR = 3.55, CI: 3.11-4.05) presents higher MMR. Additionally, black women showed the highest MMR (OR = 4.67, CI: 4.18-5.22), as well as mothers with no educational background (OR = 5.83, CI: 4.82-7.06). Conclusion: The epidemiological profile studied is predominantly composed of mothers with little or no formal education, self-declared as Black, residing in needy states and with advanced aged. These data are useful for formulating public policies aimed at combating the issue.

A Global View of Pemphigus: Geographical Variations.

Pemphigus, an autoimmune intraepidermal bullous disease group with roughly eight distinct forms, includes pemphigus vulgaris (PV) and pemphigus foliaceus (PF) as its predominant global forms. Despite the increased utilization of global health records and reporting systems, epidemiological data remain limited and poorly categorized. Therefore, this study aimed to conduct a review to track, identify, and characterize cases of PV and PF published and categorized worldwide. A research question was formulated; studies were selected based on the inclusion criteria; and data from these publications were systematically collected, summarized, and presented using narrative descriptions. The search strategy yielded 3,212 articles, of which 95 underwent critical analysis and data extraction. Studies from 52 countries contributed to the dataset, covering various pemphigus variants. Notably, only two countries, Iran (18.87%) and South Korea (11.43%), accounted for approximately a third of the reported PV cases, while Brazil contributed 40.25% of the foliaceus variants cases documented in the literature. These findings offer valuable insights into the global distribution of pemphigus and inform future research and healthcare efforts.

Elevated NS1 serum levels reduce CD119 expression and CXCL-10 synthesis in patients with dengue hemorrhagic fever.

BACKGROUND: The intensity of dengue virus (DV) replication and circulating non-structural protein 1 (NS1) levels may promote changes in the human immune response and favor severe forms of infection. We investigated the correlations between NS1 with CXCL-8, CXCL-10, IFN-γ, and IL-12p40 serum levels, and IFN-γ receptor α chain (CD119) expression, and CXCL10 production by peripheral blood mononuclear cells (PBMCs) stimulated with recombinant IFN-γ in DV-infected patients with different clinical forms. METHODS: Dengue virus NS1, CXCL-8, CXCL-10, IFN-γ, and IL-12p40 serum levels were measured in 152 DV-infected patients with different clinical forms and 20 non-infected individuals (NI) using enzyme-linked immunosorbent assay (ELISA). In addition, we investigated the CXCL-10 production after in vitro IFN-γ stimulation of PBMCs from 48 DV-infected individuals (with different clinical forms of dengue fever) and 20 NI individuals using ELISA, and CD119 expression on CD14+ cells with flow cytometry. RESULTS: Patients with dengue hemorrhagic fever (DHF) had significantly higher NS1, CXCL-8, and CXCL-10 serum levels than those with classic dengue fever (DF). The response of PBMCs to IFN-γ stimulation was lower in patients with DHF than in those with DF or dengue with complications (DWC), with lower CD119 expression and reduced CXCL-10 synthesis. In addition, these alterations are associated with high NS1 serum levels. CONCLUSIONS: Patients with DHF reported high NS1 levels, low CD119 expression, and low CXCL-10 synthesis in PBMCs, which may be associated with infection progression and severity.

Genetic variation of FcγRIIa induces higher uptake of Leishmania infantum and modulates cytokine production by adherent mononuclear cells in vitro.

Introduction: Single nucleotide variations (SNVs) are specific genetic variations that commonly occur in a population and often do not manifest phenotypically. However, depending on their location and the type of nucleotide exchanged, an SNV can alter or inhibit the function of the gene in which it occurs. Immunoglobulin G (IgG) receptor genes have exhibited several polymorphisms, including rs1801274, which is found in the FcgRIIa gene. The replacement of A with T results in a Histidine (H) to Arginine (R) substitution, altering the affinity of the IgG receptor for IgG subtypes and C-reactive protein (CRP). In this study, we analyzed rs1801274 and its functional implications concerning L. Infantum uptake and cytokine production. Methods: We genotyped 201 individuals from an endemic area for visceral leishmaniasis to assess the presence of rs1801274 using Taqman probes for a candidate gene study. Additionally, we included seventy individuals from a non-endemic area for a functional study. Subsequently, we isolated and cultivated one-week adherent mononuclear cells (AMCs) derived from the peripheral blood of participants residing in the non-endemic region in the presence of L. infantum promastigotes, with and without antigen-specific IgG and/or CRP. We analyzed the rate of phagocytosis and the production of nitric oxide (NO), tumor necrosis factor (TNF)-a, interleukin (IL)-10, IL-12 p70, IL-1b, IL- 6, and IL-8 in the culture supernatants. Results and discussion: In participants from the endemic region, the A/G (H/R isoform) heterozygous genotype was significantly associated with susceptibility to the disease. Furthermore, SNVs induced a change in the phagocytosis rate in an opsonin-dependent manner. Opsonization with IgG increased the production of IL-10, TNF-a, and IL-6 in AMCs with the H/R isoform, followed by a decrease in NO production. The results presented here suggest that the rs1801274 polymorphism is linked to a higher susceptibility to visceral leishmaniasis.

Metallic nanoparticles and treatment of cutaneous leishmaniasis: A systematic review.

BACKGROUND: Cutaneous leishmaniasis (LC) is an infectious vector-borne disease caused by parasites belonging to the genus Leishmania. Metallic nanoparticles (MNPs) have been investigated as alternatives for the treatment of LC owing to their small size and high surface area. Here, we aimed to evaluate the effect of MNPs in the treatment of LC through experimental, in vitro and in vivo investigations. METHODS: The databases used were MEDLINE/ PubMed, Scopus, Web of Science, Embase, and Science Direct. Manual searches of the reference lists of the included studies and grey literature were also performed. English language and experimental in vitro and in vivo studies using different Leishmania species, both related to MNP treatment, were included. This study was registered in PROSPERO (CRD42021248245). RESULTS: A total of 93 articles were included. Silver nanoparticles are the most studied MNPs, and L. tropica is the most studied species. Among the mechanisms of action of MNPs in vitro, we highlight the production of reactive oxygen species, direct contact of MNPs with the biomolecules of the parasite, and release of metal ions. CONCLUSION: MNPs may be considered a promising alternative for the treatment of LC, but further studies are needed to define their efficacy and safety.