Induction of CD4+CD25+FOXP3+ Regulatory T Cells during Human Hookworm Infection Modulates Antigen-Mediated Lymphocyte Proliferation

Hookworm infection is considered one of the most important poverty-promoting neglected tropical diseases, infecting 576 to 740 million people worldwide, especially in the tropics and subtropics. These blood-feeding nematodes have a remarkable ability to downmodulate the host immune response, protecting themselves from elimination and minimizing severe host pathology. While several mechanisms may be involved in the immunomodulation by parasitic infection, experimental evidences have pointed toward the possible involvement of regulatory T cells (Tregs) in downregulating effector T-cell responses upon chronic infection. However, the role of Tregs cells in human hookworm infection is still poorly understood and has not been addressed yet. In the current study we observed an augmentation of circulating CD4+CD25+FOXP3+ regulatory T cells in hookworm-infected individuals compared with healthy non-infected donors. We have also demonstrated that infected individuals present higher levels of circulating Treg cells expressing CTLA-4, GITR, IL-10, TGF-β and IL-17. Moreover, we showed that hookworm crude antigen stimulation reduces the number of CD4+CD25+FOXP3+ T regulatory cells co-expressing IL-17 in infected individuals. Finally, PBMCs from infected individuals pulsed with excreted/secreted products or hookworm crude antigens presented an impaired cellular proliferation, which was partially augmented by the depletion of Treg cells. Our results suggest that Treg cells may play an important role in hookworm-induced immunosuppression, contributing to the longevity of hookworm survival in infected people

Fibrates for the Treatment of Primary Biliary Cholangitis Unresponsive to Ursodeoxycholic Acid: An Exploratory Study

Aim: Up to 40% of patients with primary biliary cholangitis (PBC) will have a suboptimal biochemical response to ursodeoxycholic acid (UDCA), which can be improved by the addition of fibrates. This exploratory study aims to evaluate the long-term real-life biochemical response of different fibrates, including ciprofibrate, in subjects with UDCA-unresponsive PBC.Methods: The Brazilian Cholestasis Study Group multicenter database was reviewed to assess the response rates to UDCA plus fibrates in patients with UDCA-unresponsive PBC 1 and 2 years after treatment initiation by different validated criteria.Results: In total, 27 patients (100% women, mean age 48.9 +/- 9.2 years) with PBC were included. Overall response rates to fibrates by each validated criterion varied from 39 to 60% and 39-76% at 12 and 24 months after treatment combination, respectively. Combination therapy resulted in a significant decrease in ALT and ALP only after 2 years, while GGT significantly improved in the first year of treatment. Treatment response rates at 1 and 2 years appear to be comparable between ciprofibrate and bezafibrate using all available criteria.Conclusion: Our findings endorse the efficacy of fibrate add-on treatment in PBC patients with suboptimal response to UDCA. Ciprofibrate appears to be at least as effective as bezafibrate and should be assessed in large clinical trials as a possibly new, cheaper, and promising option for treatment of UDCA-unresponsive PBC patients

Response to Ursodeoxycholic Acid May Be Assessed Earlier to Allow Second-Line Therapy in Patients with Unresponsive Primary Biliary Cholangitis

Background Response to ursodeoxycholic acid (UDCA) in primary biliary cholangitis (PBC) has been traditionally assessed 1 to 2 years after treatment initiation. With the development of new drugs, some patients may benefit from an earlier introduction of second-line therapies. Aims This study aims to identify whether well-validated response criteria could correctly identify individuals likely to benefit from add-on second-line therapy at 6 months. Methods Analysis of a multicenter retrospective cohort which included only patients with clear-cut PBC. Results 206 patients with PBC (96.6% women; mean age 54 +/- 12 years) were included. Kappa concordance was substantial for Toronto (0.67), Rotterdam (0.65), Paris 1 (0.63) and 2 (0.63) criteria at 6 and 12 months, whereas Barcelona (0.47) and POISE trial (0.59) criteria exhibited moderate agreement. Non-response rates to UDCA was not statistically different when assessed either at 6 or 12 months using Toronto, Rotterdam or Paris 2 criteria. Those differences were even smaller or absent in those subjects with advanced PBC. Mean baseline alkaline phosphatase was 2.73 +/- 1.95 times the upper limit of normal (x ULN) among responders versus 5.05 +/- 3.08 x ULN in non-responders (p < 0.001). Conclusions After 6 months of treatment with UDCA, the absence of response by different criteria could properly identify patients who could benefit from early addition of second-line therapies, especially in patients with advanced disease or high baseline liver enzymes levels