Fetal allotransplant recipients are resistant to graft-versus-host disease.

In utero hematopoietic cell transplantation (IUHCT) is an experimental treatment for congenital hemoglobinopathies, including Sickle cell disease and thalassemias. One of the principal advantages of IUHCT is the predisposition of the developing fetus toward immunologic tolerance. This allows for engraftment across immune barriers without immunosuppression and, potentially, decreased susceptibility to graft-versus-host disease (GVHD). We demonstrate fetal resistance to GVHD following T cell-replete allogeneic hematopoietic cell transplantation compared with the neonate. We show that this resistance is associated with elevated fetal serum interleukin-10 conducive to the induction of regulatory T cells (Tregs). Finally, we demonstrate that the adoptive transfer of Tregs from IUHCT recipients to neonates uniformly prevents GVHD, recapitulating the predisposition to tolerance observed after fetal allotransplantation. These findings demonstrate fetal resistance to GVHD following hematopoietic cell transplantation and elucidate Tregs as important contributors.

Severe asthma and eligibility for biologics in a Brazilian cohort.

OBJECTIVE: This study aims to describe the eligibility for biologic therapies for severe asthma (SA) in a cohort of patients attending the Program for Control of Asthma (ProAR) in Bahia, Brazil. METHODS: Data from SA patients (≥18 years old) attending the ProAR, that were included in a case-control study conducted from 2013 to 2015, were used to reassess patients according to a modified ERS/ATS 2014 SA criteria. Patients were then classified according to the eligibility for SA biological therapy based on current prescription labels. RESULTS: From 544 patients in the cohort, 531 (97.6%) were included and 172 (32.4%) were identified as SA patients according to the ERS/ATS 2014 modified criteria. Of these 172 patients, 69 (40.1%) were ineligible for any of the biologicals approved for asthma (omalizumab, mepolizumab, reslizumab and benralizumab), 60 (34.9%) patients were eligible for one of the biological therapies, and 10 (5.8%) patients were eligible for all biological therapies. CONCLUSIONS: More than half of patients with SA were eligible for biologic therapy in our study, but none of them received this form of treatment. Almost half of them were not eligible to any of the approved biologics, however. The variability and overlap in patients' eligibility highlight the importance of evaluating each patient individually for a more personalized treatment approach. While there is a need to increase access for some of those eligible that may really need a biologic treatment, continuous efforts are required to develop alternatives to those who are not eligible.

Regulatory T cells promote alloengraftment in a model of late-gestation in utero hematopoietic cell transplantation.

In utero hematopoietic cell transplantation (IUHCT) has the potential to cure congenital hematologic disorders including sickle cell disease. However, the window of opportunity for IUHCT closes with the acquisition of T-cell immunity, beginning at approximately 14 weeks gestation, posing significant technical challenges and excluding from treatment fetuses evaluated after the first trimester. Here we report that regulatory T cells can promote alloengraftment and preserve allograft tolerance after the acquisition of T-cell immunity in a mouse model of late-gestation IUHCT. We show that allografts enriched with regulatory T cells harvested from either IUHCT-tolerant or naive mice engraft at 20 days post coitum (DPC) with equal frequency to unenriched allografts transplanted at 14 DPC. Long-term, multilineage donor cell chimerism was achieved in the absence of graft-versus-host disease or mortality. Decreased alloreactivity among recipient T cells was observed consistent with donor-specific tolerance. These findings suggest that donor graft enrichment with regulatory T cells could be used to successfully perform IUHCT later in gestation.

Asthma similarities across ProAR (Brazil) and U-BIOPRED (Europe) adult cohorts of contrasting locations, ethnicity and socioeconomic status.

BACKGROUND: Asthma prevalence is 339 million globally. 'Severe asthma' (SA) comprises subjects with uncontrolled asthma despite proper management. OBJECTIVES: To compare asthma from diverse ethnicities and environments. METHODS: A cross-sectional analysis of two adult cohorts, a Brazilian (ProAR) and a European (U-BIOPRED). U-BIOPRED comprised of 311 non-smoking with Severe Asthma (SAn), 110 smokers or ex-smokers with SA (SAs) and 88 mild to moderate asthmatics (MMA) while ProAR included 544 SA and 452 MMA. Although these projects were independent, there were similarities in objectives and methodology, with ProAR adopting operating procedures of U-BIOPRED. RESULTS: Among SA subjects, age, weight, proportion of former smokers and FEV1 pre-bronchodilator were similar. The proportion of SA with a positive skin prick tests (SPT) to aeroallergens, the scores of sino-nasal symptoms and quality of life were comparable. In addition, blood eosinophil counts (EOS) and the % of subjects with EOS > 300 cells/µl were not different. The Europeans with SA however, were more severe with a greater proportion of continuous oral corticosteroids (OCS), worse symptoms and more frequent exacerbations. FEV1/FVC pre- and post-bronchodilator were lower among the Europeans. The MMA cohorts were less comparable in control and treatment, but similar in the proportion of allergic rhinitis, gastroesophageal reflux disease and EOS >3%. CONCLUSIONS: ProAR and U-BIOPRED cohorts, with varying severity, ethnicity and environment have similarities, which provide the basis for global external validation of asthma phenotypes. This should stimulate collaboration between asthma consortia with the aim of understanding SA, which will lead to better management.

Eosinophilic asthma, according to a blood eosinophil criterion, is associated with disease severity and lack of control among underprivileged urban Brazilians.

BACKGROUND: Asthma is a syndrome with multiple phenotypes. Peripheral blood eosinophil counts might be the ideal biomarker to identify subjects with eosinophilic asthma. It is available, inexpensive, and it is associated with eosinophilia in sputum. OBJECTIVE: The aim of this study was to evaluate whether blood eosinophilia is associated with asthma severity and to evaluate whether blood eosinophilia is associated with lack of control of asthma symptoms and airway obstruction. METHODS: Case control study. The cases were subjects recruited from a cohort of patients with severe asthma, in Salvador-BR, demanding continuous inhaled corticosteroids and LABA. There were two control groups: 1) subjects with mild/moderate asthma, 2) subjects with no asthma. Subjects enrolled in the study answered questionnaires, had their blood and stool samples collected, performed spirometry and SPT. We established a cutoff ≥ 260 cells/mm3 for blood eosinophilia. RESULTS: We evaluated 544 subjects in the case group, 452 subjects with mild to moderate asthma and 450 subjects with no asthma. The subjects of the case group had higher odds of presenting the eosinophilic phenotype in comparison to subjects with mild to moderate asthma [OR 1.60 95CI(1.19-2.16)] and no asthma [OR 3.93; 95CI(2.90-5.33)]. The eosinophilic phenotype, according to blood count, is associated with uncontrolled asthma [OR 1.56; 95CI(1.06-2.28)], but it is not associated with airway obstruction [OR 0.87; 95CI(0.61-1.24)]. CONCLUSION: We conclude that the blood eosinophilia is a biomarker associated with asthma severity and poor symptom control, but we found no association with reduced lung function.

Umeclidinium/vilanterol as step-up therapy from tiotropium in patients with moderate COPD: a randomized, parallel-group, 12-week study.

INTRODUCTION: Patients with COPD who remain symptomatic on long-acting bronchodilator monotherapy may benefit from step-up therapy to a long-acting bronchodilator combination. This study evaluated the efficacy and safety of umeclidinium (UMEC)/vilanterol (VI) in patients with moderate COPD who remained symptomatic on tiotropium (TIO). METHODS: In this randomized, blinded, double-dummy, parallel-group study (NCT01899742), patients (N=494) who were prescribed TIO for ≥3 months at screening (forced expiratory volume in 1 s [FEV1]: 50%-70% of predicted; modified Medical Research Council [mMRC] score ≥1) and completed a 4-week run-in with TIO were randomized to UMEC/VI 62.5/25 µg or TIO 18 µg for 12 weeks. Efficacy assessments included trough FEV1 at Day 85 (primary end point), 0-3 h serial FEV1, rescue medication use, Transition Dyspnea Index (TDI), St George's Respiratory Questionnaire (SGRQ), and COPD Assessment Test (CAT). Safety evaluations included adverse events (AEs). RESULTS: Compared with TIO, UMEC/VI produced greater improvements in trough FEV1 (least squares [LS] mean difference: 88 mL at Day 85 [95% confidence interval {CI}: 45-131]; P<0.001) and FEV1 after 5 min on Day 1 (50 mL [95% CI: 27-72]; P<0.001). Reductions in rescue medication use over 12 weeks were greater with UMEC/VI versus TIO (LS mean change: -0.1 puffs/d [95% CI: -0.2-0.0]; P≤0.05). More patients achieved clinically meaningful improvements in TDI score (≥1 unit) with UMEC/VI (63%) versus TIO (49%; odds ratio at Day 84=1.78 [95% CI: 1.21-2.64]; P≤0.01). Improvements in SGRQ and CAT scores were similar between treatments. The incidence of AEs was similar with UMEC/VI (30%) and TIO (31%). CONCLUSION: UMEC/VI step-up therapy provides clinical benefit over TIO monotherapy in patients with moderate COPD who are symptomatic on TIO alone.