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.

Anti-inflammatory actions of aspirin-triggered resolvin D1 (AT-RvD1) in bronchial epithelial cells stimulated by cigarette smoke extract.

Smoking causes several diseases such as chronic obstructive pulmonary disease (COPD). Aspirin-triggered-resolvin D1 (AT-RvD1) is a lipid mediator produced during the resolution of inflammation and demonstrates anti-inflammatory and pro-resolution effects in several inflammatory experimental models including in the airways. Here we evaluated the role of AT-RvD1 (100 nM) in bronchial epithelial cells (BEAS-2B) stimulated by cigarette smoke extract (CSE; 1%; 1 cigarette) for 24 h. CSE induced the productions of IL-1ß, TNF-α, IL-10, IL-4 and IFN-γ as well as the activations of NF-κB and STAT3 and the expression of ALX/FPR2 receptor. AT-RvD1 reduced the IL-1ß and TNF-α production and increased the production of IFN-γ. These effects were reversed BOC2, an antagonist of ALX/FPR2 receptor for AT-RvD1. The production of IL-4 and IL-10 were not altered by AT-RvD1. In addition, AT-RvD1 reduced the phosphorylation of NF-κB and STAT3 when compared to CSE-stimulated BEAS-2B cells. No alteration of ALX/FPR2 expression was observed by AT-RvD1 when compared to CSE group. In the human monocytic leukemia cell line, the relative number of copies of IL-1ß and IL-4 was significantly higher in CSE + AT-RvD1 group compared CSE group, however, the expression of M1 cytokine was more pronounced than M2 profile. AT-RvD1 could be an important target for the reduction of inflammation in the airways associated with smoking.

Inflammatory Response and Activation of Coagulation after COVID-19 Infection.

SARS-CoV-2 (COVID-19) infection is responsible for causing a disease with a wide spectrum of clinical presentations. Predisposition to thromboembolic disease due to excessive inflammation is also attributed to the disease. The objective of this study was to characterize the clinical and laboratory aspects of hospitalized patients, in addition to studying the pattern of serum cytokines, and associate them with the occurrence of thromboembolic events. METHODOLOGY: A retrospective cohort study with 97 COVID-19 patients hospitalized from April to August 2020 in the Triângulo Mineiro macro-region was carried out. A review of medical records was conducted to evaluate the clinical and laboratory aspects and the frequency of thrombosis, as well as the measurement of cytokines, in the groups that presented or did not present a thrombotic event. RESULTS: There were seven confirmed cases of thrombotic occurrence in the cohort. A reduction in the time of prothrombin activity was observed in the group with thrombosis. Further, 27.8% of all patients had thrombocytopenia. In the group that had thrombotic events, the levels of IL1b, IL-10, and IL2 were higher (p < 0.05). CONCLUSIONS: In the studied sample, there was an increase in the inflammatory response in patients with thrombotic events, confirmed by the increase in cytokines. Furthermore, in this cohort, a link was observed between the IL-10 percentage and an increased chance of a thrombotic event.

Leukoreduction as a control measure in transfusion transmission of visceral leishmaniasis.

BACKGROUND: Asymptomatic visceral leishmaniasis (VL) infection is a risk for transfusion safety. Leukoreduction has been an alternative for the prevention of some blood-borne diseases, including VL. This study aimed to evaluate the role of leukoreduction of cellular blood components as a control measure for transfusional VL transmission. RESEARCH DESIGN AND METHODS: A total of 161 polytransfused patients with non-leukoreduced blood components (HNL), 95 polytransfused with leukoreduced blood components (LH), and 202 non-transfused (NT) from endemic regions for VL and with a similar epidemiological profile. The detection of antibodies against VL was performed by ELISA and the presence of the parasite was investigated by real-time PCR. Statistical significance was defined as p < .05. RESULTS: When comparing three groups, ELISA results were statistically significant (p = .0065). The residual analysis of ELISA showed statistically significant for the HNL group compared to the general group (p = .002; OR: 5.6; CI: 1.7-25.8), demonstrating that individuals who received non-leukoreduced transfusions are five times more likely to acquire Leishmania infantum infection than the general. DISCUSSION: Higher prevalence in the group with HNL and low prevalence in those who received LH, similar to NT patients, highlight the risk of transfusional VL transmission and reinforce the role of leukoreduction in its prevention.

Evaluation of Specific Cellular and Humoral Immune Response to Toxoplasma gondii in Patients with Autoimmune Rheumatic Diseases Immunomodulated Due to the Use of TNF Blockers.

(1) Background: TNF antagonists have been used to treat autoimmune diseases (AD). However, during the chronic phase of toxoplasmosis, TNF-α and TNFR play a significant role in maintaining disease resistance and latency. Several studies have demonstrated the risk of latent infections' reactivation in patients infected with toxoplasmosis. Our objective was to verify whether patients with autoimmune rheumatic diseases, who use TNF antagonists and/or synthetic drugs and had previous contact with Toxoplasma gondii (IgG+), present any indication of an increased risk of toxoplasmosis reactivation. (2) Methods: Blood samples were collected, and peripheral blood mononuclear cells (PBMCs) were evaluated after stimulation with antigens of Toxoplasma gondii, with anti-CD3/anti-CD28 or without stimulus, at 48 and 96 h. CD69+, CD28+, and PD-1 stains were evaluated, in addition to intracellular expression of IFN-γ, IL-17, and IL-10 by CD4+ and the presence of regulatory CD4+ T cells by labeling CD25+, FOXP3, and LAP. The cytokines IL-2, IL-4, IL-6, IL-10, IFN-γ, TNF-α, and IL-17 were measured in the culture supernatant after 96 h. Serology for IgG and IgG1 was evaluated. (3) Results: There were no differences in the levels of IgG and IgG1 between the groups, but the IgG1 avidity was reduced in the immunobiological group compared to the control group. All groups exhibited a significant correlation between IgG and IgG1 positivity. CD4+ T lymphocytes expressing PD-1 were increased in individuals suffering from autoimmune rheumatic diseases and using disease-modifying antirheumatic drugs. In addition, treatment with TNF blockers did not seem to influence the populations of regulatory T cells and did not interfere with the expression of the cytokines IFN-γ, IL-17, and IL-10 by CD4+ cells or the production of cytokines by PBMCs from patients with AD. (4) Conclusions: This study presents evidence that the use of TNF-α blockers did not promote an immunological imbalance to the extent of impairing the anti-Toxoplasma gondii immune response and predisposing to toxoplasmosis reactivation.

Effects of combination of Cryptococcus gattii and IFN-γ, IL-4 or IL-27 on human bronchial epithelial cells.

BACKGROUND: Airway epithelial cells are crucial for the establishment of cryptococcosis. In experimental cryptococcosis, the Th2 immune response is associated with host susceptibility, while Th1 cells are associated with protection. The absence of IL-27 receptor alpha in mice favor the increase Cryptococcus neoformans burden in the lung. Here, we evaluated the effects of the combination of IL-4, IFN-γ or IL-27 with C. gattii on human bronchial epithelial cells (BEAS-2B). METHODS: BEAS-2B were stimulated with IL-4, IFN-γ or IL-27 (100 ng/mL) and/or live yeast forms of C. gattii (multiplicities of infection (MOI) of 1-100) and vice-versa, as well as with heat-killed cells of C. gattii for 24 h. RESULTS: None of the C. gattii MOIs had cytotoxic effects on BEAS-2B when compared to control. The cells stimulated by cytokines (IL-4, IFN-γ or IL-27) followed by live yeast forms of C. gattii (MOI of 100) infection and vice-versa demonstrated a reduction in IL-6, IL-8 and/or CCL2 production and activation of STAT6 (induced by IL-4) and STAT1 (induced by IL-27 or IFN-γ) when compared to cells stimulated with C. gattii, IL-4, IFN-γ or IL-27. In the combination of cytokines and heat-killed cells of C. gattii, no inhibition of these inflammatory parameters was observed. The growth of C. gattii was increased while the phagocytosis of live yeast forms of C. gattii in the BEAS-2B were reduced in the presence of IL-4, IFN-γ or IL-27. Conclusion The association of live yeast forms, but not heat-killed yeast forms, of C. gattii with IL-4, IFN-γ or IL-27 induced an anti-inflammatory effect.

Development of Ag-ZnO/AgO Nanocomposites Effectives for Leishmania braziliensis Treatment.

Tegumentary leishmaniasis (TL) is caused by parasites of the genus Leishmania. Leishmania braziliensis (L.b) is one of the most clinically relevant pathogens that affects the skin and mucosa, causing single or multiple disfiguring and life-threatening injuries. Even so, the few treatment options for patients have significant toxicity, high dropout rates, high cost, and the emergence of resistant strains, which implies the need for studies to promote new and better treatments to combat the disease. Zinc oxide nanocrystals are microbicidal and immunomodulatory agents. Here, we develop new Ag-ZnO/xAgO nanocomposites (NCPs) with three different percentages of silver oxide (AgO) nanocrystals (x = 49%, 65%, and 68%) that could act as an option for tegumentary leishmaniasis treatment. Our findings showed that 65% and 68% of AgO inhibit the extra and intracellular replication of L.b. and present a high selectivity index. Ag-ZnO/65%AgO NCPs modulate activation, expression of surface receptors, and cytokine production by human peripheral blood mononuclear cells toward a proinflammatory phenotype. These results point to new Ag-ZnO/AgO nanocomposites as a promising option for L. braziliensis treatment.

Association of gestational diabetes mellitus and negative modulation of the specific humoral and cellular immune response against Toxoplasma gondii.

In order to evaluate and compare the specific immune response of pregnant women (PW) chronically infected with Toxoplasma gondii, with and without gestational diabetes mellitus (GDM), and the humoral response of their respective newborns (NB), the study was carried out on 81 PW (34 GDM and 47 controls) from whose medical records the results of the oral glucose tolerance test (OGTT) were obtained, and blood samples were collected at the third trimester of pregnancy; also, on 45 NBs (20 GDM and 25 controls) from whom umbilical cord blood samples were obtained. Humoral immunity was analyzed by measuring anti-T. gondii total IgG, IgG subclasses and IgG avidity. To evaluate cellular immunity, peripheral blood mononuclear cells (PBMC) from 32 PW (16 GDM and 16 controls) were cultured, supernatant cytokines were determined, and flow cytometry was performed to analyze the expression at lymphocytes of surface molecules, cytokines and transcription factors. All PW and NBs were positive for total IgG, and the prevalent subclass was IgG1. There was a negative correlation between the OGTT glycemia of PW and the levels of total IgG, IgG1 and IgG avidity. The IgG avidity of the GDM group was significantly lower than the control group. Patients from the GDM group had a higher number of T lymphocytes expressing markers of cell activation and exhaustion (CD28 and PD-1). In the presence of T. gondii soluble antigen (STAg) the amount of CD4+ T cells producing IFN-γ, IL-10 and IL-17 was significantly lower in the GDM group, while there was no difference between groups in the number of CD4+ CD25HighFOXP3+LAP+ functional Treg cells. Additionally, under STAg stimulus, the secretion of IL-17, IL-4, TNF and IL-2 cytokines at PBMCs culture supernatant was lower in the GDM group. In conclusion, there was a correlation between the increase in blood glucose and the decrease in levels of anti-T. gondii antibodies, associated with the decreased IgG avidity in patients who develop GDM. Also, the GDM group had decreased immune responses in Th1, Th2 and Th17 profiles, suggesting an association between GDM and the negative modulation of the humoral and cellular immune responses against T. gondii.

Specific Human ATR and ATM Inhibitors Modulate Single Strand DNA Formation in Leishmania major Exposed to Oxidative Agent.

Leishmania parasites are the causative agents of a group of neglected tropical diseases known as leishmaniasis. The molecular mechanisms employed by these parasites to adapt to the adverse conditions found in their hosts are not yet completely understood. DNA repair pathways can be used by Leishmania to enable survival in the interior of macrophages, where the parasite is constantly exposed to oxygen reactive species. In higher eukaryotes, DNA repair pathways are coordinated by the central protein kinases ataxia telangiectasia mutated (ATM) and ataxia telangiectasia and Rad3 related (ATR). The enzyme Exonuclease-1 (EXO1) plays important roles in DNA replication, repair, and recombination, and it can be regulated by ATM- and ATR-mediated signaling pathways. In this study, the DNA damage response pathways in promastigote forms of L. major were investigated using bioinformatics tools, exposure of lineages to oxidizing agents and radiation damage, treatment of cells with ATM and ATR inhibitors, and flow cytometry analysis. We demonstrated high structural and important residue conservation for the catalytic activity of the putative LmjEXO1. The overexpression of putative LmjEXO1 made L. major cells more susceptible to genotoxic damage, most likely due to the nuclease activity of this enzyme and the occurrence of hyper-resection of DNA strands. These cells could be rescued by the addition of caffeine or a selective ATM inhibitor. In contrast, ATR-specific inhibition made the control cells more susceptible to oxidative damage in an LmjEXO1 overexpression-like manner. We demonstrated that ATR-specific inhibition results in the formation of extended single-stranded DNA, most likely due to EXO1 nucleasic activity. Antagonistically, ATM inhibition prevented single-strand DNA formation, which could explain the survival phenotype of lineages overexpressing LmjEXO1. These results suggest that an ATM homolog in Leishmania could act to promote end resection by putative LmjEXO1, and an ATR homologue could prevent hyper-resection, ensuring adequate repair of the parasite DNA.

RhoA/ROCKs signaling is increased by treatment with TKI-258 and leads to increased apoptosis in SCC-4 oral squamous cell carcinoma cell line.

BACKGROUND: This study evaluated the effect of treatment with TKI-258 on apoptosis, involving Rho GTPases and their effectors in SCC-4 cells of oral squamous cell carcinoma. METHODS: Markers of cell death and apoptosis were analyzed in control and TKI-258-treated SCC-4 cells by flow cytometry. The involvement of Rho GTPases and effectors in the induction of apoptosis by TKI-258 was evaluated by quantification of cleaved PARP. Also, gene expression analysis of those proteins was performed. RESULTS: The treatment with TKI-258 led to a significant increase in cell death (7-AAD) and apoptosis (annexin V and cleaved PARP). When Rho GTPases were stimulated with LPA and inhibited with toxin A Clostridium difficile, the percentage of apoptotic cells increased and decreased, respectively. A similar effect was found when the treatment was with TKI-258 combined with LPA and toxin A. Treatment with TKI-258 significantly increased RhoA gene expression, while RhoB, RhoC, Rac1, and Cdc42 decreased significantly. ROCKs inhibitors (Y-27632 and HA-1077) reduced apoptosis compared with control. TKI-258 combined with Y-27632 or HA-1077 led to an increase in apoptosis compared with inhibitors only. Treatment with TKI-258 led to an increase in ROCK1 and ROCK2 gene expression, and a decrease in PAK1 and PAK2 gene expression. CONCLUSIONS: TKI-258 stimulates apoptosis in SCC-4 cells of oral squamous cell carcinoma. Possibly, RhoA GTPase and their effectors ROCKs participate in the signaling pathway inhibited by TKI-258. CLINICAL RELEVANCE: Therapies with multi-target inhibitors, such as TKI-258, may be promising alternatives for the clinical treatment of oral squamous cell carcinoma.

Identification of Leishmania infantum in blood donors from endemic regions for visceral leishmaniasis.

Visceral leishmaniasis is an endemic protozoonosis observed in over 60 countries, with over 500 000 new cases recorded annually. Although the diagnostic procedure of its symptomatic forms is well established, for asymptomatic patients, who represent about 85% of those infected, there is no consensus on the best method for its identification. Recent studies have presented molecular techniques as viable identification methods, with good sensitivity and specificity indices in asymptomatic individuals. Therefore, we aimed to use molecular methods to assess their effectiveness in identifying the presence of asymptomatic infection by Leishmania infantum (L. infantum) individuals from endemic regions of Brazil. Screening was performed by real-time polymerase chain reaction (qPCR) and confirmed by sequencing the cytochrome B gene. Of the 127 samples [from 608 blood donors who had participated in a previous study, of which 34 were positive by the enzyme-linked immunosorbent assay (ELISA) rK39] tested by qPCR, 31 (24.4%) were positive. In the sequencing of 10 qPCR-positive samples, five were identified as L. infantum. Complimentary samples of the ELISA rK39 and conventional PCR showed only reasonable and low agreement with qPCR, respectively. The qPCR confirmed the presence of infection in five of the 10 sequenced samples, ELISA confirmed three, and the conventional PCR confirmed none.

Male sickle cell patients, compensated transpubertal hypogonadism and normal final growth.

OBJECTIVE: Investigate the gonadal hormonal function in sickle cell individuals. CONTEXT: Sickle cell disease (SCD) is associated with delayed physical and sexual development, and it has been related to both primary testicular failure and hypothalamo-pituitary-gonadal axis abnormalities. DESIGN: The study of the pituitary gonadotrophin reserve was done evaluating the hormonal levels before and after stimulation by gonadoliberin. PATIENTS: Male patients with homozygous SCD (18-39 years, median = 29.5 years). MEASUREMENTS: Gonadal function was evaluated through clinical parameters and the hormonal quantification. RESULTS: Although low body weight and other clinical signs of undernutrition such as clinical hypoandrogenism and the extreme retardation of puberty were seen in these patients, final stature and hormonal testicular reserve to hCG stimulation were proved to be normal according to our previous data. In the present investigation, the basal luteotropic gonadotropin (LH), follicle-stimulating hormone (FSH) and testosterone (T) levels were similar between the patients and controls. Prostate-specific antigen (PSA) levels-used as a biochemical marker of androgenicity, mainly in puberty-were lower in the patients than in the controls and were only correlated with T. A subtle abnormality in the pituitary responsivity to gonadotropin-releasing hormone (GnRH) was disclosed, with a higher response to LH 60 minutes after stimulation in patients than in controls. CONCLUSIONS: These data, in addition to both the clinical and biochemical signs of hypoandrogenism associated with normal to elevated T levels strongly suggest a peripheral origin of hypogonadism, which is probably due to androgen resistance in the patients with SCD.

Applicability of an instrument to identify human leukocyte antigen-compatible donors for platelet transfusions.

BACKGROUND: The selection of compatible human leukocyte antigen platelets has been associated with improved platelet increments. Therefore, an effective strategy would be the selection of donors who are genetically compatible according to the human leukocyte antigen system. Nonetheless, this is costly as it concerns a highly polymorphic system, which requires a large bank of genotyped donors. METHODS: This study evaluated the feasibility of virtual crossmatching using EpVix software, which simplifies the identification of compatible donors or donors with acceptable incompatibilities. RESULTS: Forty-three oncohematological patients were evaluated, in 96 platelet transfusion episodes with 16.3% of the patients being found to be refractory to platelet transfusions. Eight alloimmunized, multitransfused patients were selected to evaluate human leukocyte antigen compatibility against a bank of 336 platelet donors. At least partially compatible donors were found for all patients. The number of compatible donors was found to be inversely proportional to the human leukocyte antigen-panel reactive antibody score of each patient. It was noted that five patients with scores of 15% or less had at least 190 compatible donors; four fully compatible donors were found for two other patients with scores greater than 80% and only one patient (score of 93%) did not have a fully compatible donor. However, for this last patient, 40 donors were partially compatible according to the software. CONCLUSION: The results showed the effectiveness of the use of the EpVix tool to identify potential platelet donors for multitransfused and/or alloimmunized patients, even with a small number of human leukocyte antigen genotyped donors available.

Frequency of red blood cell genotypes in multi-transfused patients and blood donors from Minas Gerais, Southeast Brazil.

BACKGROUND AND OBJECTIVES: The frequency of red blood cell (RBC) antigens in Brazil varies due to differences in the ethnic groups in different regions; however, these studies have not been performed in Minas Gerais, where African admixture is more prevalent in comparison with other states. Due to these facts, this study aimed to determine the frequency of RBC genotypes on Rh, Kell, Duffy and Kidd systems in blood donors and multi-transfused patients from Minas Gerais, Southeast Brazil. METHODS: Blood samples were collected from 170 donors and 117 patients with different diagnosis and at least three RBC transfusions. DNA was extracted from leukocytes and genotyped by PCR-SSP, Multiplex or RFLP to alleles of the referred systems. The results were compared by the Chi-Square test, with a significance level of 5%. RESULTS: The most frequent genotypes were: RHD+, RHCE*ce/RHCE*ce, KEL*2/KEL*2, FY*B-67T/FY*B-67T and JK*A/JK*B. FY*B-67C/FY*B-67C, RHD*Ψ and JK*A/JK*A genotypes were more prevalent in sickle cell disease (SCD) patients than in donors. Many differences in RBC genotype frequencies were observed in comparison with studies from other states and countries. CONCLUSION: The results reinforce the importance of determining RBC genotypes of blood donors and patients in different regions of Brazil and the world, improving the transfusion safety of individuals requiring chronic RBC transfusions, especially those with SCD, due to ethnic differences in relation to donors.

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

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.

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.

CD4+ T lymphocytopenia associated with sideropenia: case report

Importance of the issue: Idiopathic CD4 T lymphocytopenia is an unusual immune defect in which there is an unexplained deficit of CD4 T cells. This case presents a 39-year-old female patient, with CD4+ T lymphocytopenia, who was not infected with immunosuppressive viruses neither was she subjected to immunosuppressive therapies. Comments: While monitoring the patient, she was found to have very low serum ferritin and, after parenteral iron therapy, there were changes in CD4+ cell levels, indicating that, in this case, lymphocytopenia was secondary to sideropenia. The patient is being kept under strict control of serum iron and periodic immunological evaluation, and she has not showed any clinical and/or laboratory adverse events so far. It is known that iron deficiency is an important factor in the genesis of immunological changes that occur in patients with iron deficiency anemia. It is important to understand the effects of iron deficiency on the immune system due to its high prevalence worldwide. Moreover, it could also help to clarify several cases of idiopathic CD4 lymphocytopenia (AU)

Importância da questão: Linfocitopenia T CD4+ idiopática é um defeito imune incomum em que há um déficit inexplicável de células T CD4. Este caso clínico apresenta uma paciente do sexo feminino de 39 anos de idade, com linfocitopenia T CD4+, que não estava infectada por vírus imunossupressores nem foi submetida a terapias imunossupressoras. Comentários: Durante o acompanhamento da paciente, ela apresentou níveis muito baixos de ferritina sérica e, após a terapia parenteral de ferro, houve aumento da quantidade de células CD4+, indicando que, neste caso, linfocitopenia era secundária à sideropenia. A paciente estava sendo mantida sob rigoroso controle de ferro sérico e avaliação imunológica periódica, e não mostrou quaisquer eventos adversos clínicos e/ou laboratoriais até o momento. Com base em mudanças na reatividade imunológica dos pacientes observadas por outros pesquisadores após a suplementação com ferro, é evidente que a deficiência de ferro seria um fator importante na gênese das alterações imunológicas que ocorrem em pacientes com anemia ferropriva. É importante compreender os efeitos da deficiência de ferro no sistema imune, devido à sua elevada prevalência mundial. Essas informações também auxiliariam a esclarecer vários casos de linfocitopenia T CD4+ idiopática. (AU)