Seroprevalence of Antitransglutaminase and Antiendomysium Antibodies in Adult Colombian Blood Bank Donors.

Celiac disease (CD) is an autoimmune enteropathy induced by the ingestion of gluten from wheat, barley, and rye in genetically susceptible individuals. The global prevalence of CD is 1.4%. However, most of the prevalence studies have been conducted in Caucasian populations; few studies have been performed in Latin America. The aim of this study is to determine the seroprevalence of auto-antibodies used as markers for CD in a Colombian cohort. In this cross-sectional study, the serum samples from Colombian donors of the National Red Cross Blood Bank were collected between June and September 2017 in Bogotá, Colombia. All sera were tested for IgA antitissue transglutaminase (TTG) by enzyme-linked immunosorbent assay. Seropositive sera were tested for IgA antiendomysium (EMA) using indirect immunofluorescence assay. The ancestral genetic composition was determined in donor samples with antibody assay reactivity. Those with two seroreactive assays were typed for HLA class II DQ2 and DQ8. In total, 228 blood donors participated in the study. Among them, 113 were females (49.56%) with an average age of 31.63 years (SD ± 12.99); males had an average of 34.71 years (SD ± 13.01). Only 3 (1.31%) donors reported chronic diarrhea and nonintentional weight loss; 11 (4.82%) had a family history of CD. For the serological assays, 11 donors (4.82%) were seroreactive to IgA anti-TTG: 3 had high reactivity and 8 had low reactivity. Of those seroreactive to IgA anti-TTG, 3 (1.32%) were also seroreactive to anti-EMA, and they were typed as HLA-DQ8 or HLA-DQ2. The baseline ancestral percentage of the seroreactive donors was higher for European and Native American than for African genes. The seroprevalence for anti-TTG and anti-EMA with the presence of HLA-DQ8 and HLA-DQ2 was 1.32%. Additionally, 4.82% donor participants were reactive only for anti-TTG. Compared with other studies, our findings suggest that Colombia has a high prevalence of CD markers.

Percentages of CD4+CD8+ Double-positive T Lymphocytes in the Peripheral Blood of Adults from a Blood Bank in Bogotá, Colombia

Objective: CD4+CD8+ double-positive T-cells (DPTs) have been classified as a separate T-cell subpopulation, with two main phenotypes: CD4high CD8low and CD4low CD8high. In recent years, the relevance of DPTs in the pathogenesis of infections, tumors, and autoimmune diseases has been recognized. Reference values among healthy individuals remain unknown. Therefore, the aim of this study is to provide a reference value for DPTs in peripheral blood from healthy donors in a blood bank in Bogotá, Colombia, and to determine the activation status using a surface marker. Materials and Methods: One hundred healthy donors were enrolled in the study. Peripheral blood cells were stained for CD3, CD4, CD8, and CD154 (CD40L), and cellular viability was assessed with 7-aminoactinomycin D and analyzed by flow cytometry. Results: The median value for DPTs was 2.6% (interquartile range=1.70%-3.67%). Women had higher percentages of DPTs than men (3.3% vs. 2.1%). The subpopulation of CD4low CD8high showed higher expression of CD154 than the other T-cell subpopulations. Conclusion: DPT reference values were obtained from blood bank donors. A sex difference was found, and the CD4low CD8high subpopulation had the highest activation marker expression.

Intermediate Monocytes and Cytokine Production Associated With Severe Forms of Chagas Disease.

Monocytes are classified according to their CD14 and CD16 expression into classical (reparative), intermediate (inflammatory), and non-classical. This study assessed the frequency of monocyte and the relationship between monocyte subset percentages and the levels of blood cytokines in Colombian chagasic patients with different clinical forms. This study included chagasic patients in different clinical stages: indeterminate (IND) n = 14, chronic chagasic cardiomyopathy (CCC) n = 14, and heart transplant chagasic (HTCC) n = 9; controls with non-chagasic cardiopathy (NCC) n = 15, and healthy individuals (HI) n = 15. Peripheral blood mononuclear cells (PBMCs) were isolated, labeled for CD14, CD16, and HLA-DR, and analyzed by flow cytometry. Cytokines were measured with a bead-based immunoassay. Percentages of total CD14+ CD16+ and CD14+ HLA-DR+ monocytes were higher in patients with heart involvement (CCC, HTCC, and NCC) than controls. Percentages of intermediate monocytes increased in symptomatic chagasic patients (CCC and HTCC) compared to asymptomatic chagasic patients (IND) and controls (HI). Asymptomatic chagasic patients (IND) had higher percentages of classical monocytes, an increased production of CCL17 chemokine compared to chagasic symptomatic patients (CCC), and their levels of CCL17 was positively correlated with the percentage of classical monocyte subset. In CCC, the percentages of intermediate and classical monocytes were positively correlated with IL-6 levels, which were higher in this group compared to HI, and negatively with IL-12p40 concentration, respectively. Remarkably, there also was an important increased of classical monocytes frequency in three chronic chagasic patients who underwent cardiac transplant, of which one received anti-parasitic treatment. Our findings suggest that cardiac chagasic patients have an increased percentage of inflammatory monocytes and produce more IL-6, a biomarker of heart failure and left ventricular dysfunction, whereas asymptomatic chagasic individuals present a higher percentage of reparative monocytes and CCL17.