Dataset Information

Immune Activation and Bacterial Translocation: A Link between Impaired Immune Recovery and Frequent Visceral Leishmaniasis Relapses in HIV-Infected Patients.

ABSTRACT: The maintenance of chronic immune activation due to leishmaniasis or even due to microbial translocation is associated with immunosenescence and may contribute to frequent relapses. Our aim was to investigate whether patients with HIV-associated visceral leishmaniasis (VL/HIV) who experience a single episode of VL have different immunological behaviors in comparison to those who experience frequent relapses. VL/HIV patients were allocated to non-relapsing (NR, n = 6) and relapsing (R, n = 11) groups and were followed from the active phase of VL up to 12 months post-treatment (mpt). The patients were receiving highly active antiretroviral therapy (HAART) and secondary prophylaxis after VL therapy. During active VL, the two groups were similar in all immunological parameters, including the parasite load. At 6 and 12 mpt, the NR group showed a significant gain of CD4+ T cells, a reduction of lymphocyte activation, and lower soluble CD14 and anti-Leishmania IgG3 levels compared to the R group. The viral load remained low, without correlation with the activation. The two groups showed elevated but similar percentages of senescent T cells. These findings suggest a decreased ability of the R group to downmodulate immune activation compared to the NR group. Such functional impairment of the effector response may be a useful indicator for predicting clinical prognosis and recommending starting or stopping secondary prophylaxis.

SUBMITTER: Silva-Freitas ML

PROVIDER: S-EPMC5132299 | biostudies-other | 2016

REPOSITORIES: biostudies-other

ACCESS DATA

Publications

Immune Activation and Bacterial Translocation: A Link between Impaired Immune Recovery and Frequent Visceral Leishmaniasis Relapses in HIV-Infected Patients.

Silva-Freitas Maria Luciana ML Cota Glaucia Fernandes GF Machado-de-Assis Talia S TS Giacoia-Gripp Carmem C Rabello Ana A Da-Cruz Alda M AM Santos-Oliveira Joanna R JR

PloS one 20161201 12

The maintenance of chronic immune activation due to leishmaniasis or even due to microbial translocation is associated with immunosenescence and may contribute to frequent relapses. Our aim was to investigate whether patients with HIV-associated visceral leishmaniasis (VL/HIV) who experience a single episode of VL have different immunological behaviors in comparison to those who experience frequent relapses. VL/HIV patients were allocated to non-relapsing (NR, n = 6) and relapsing (R, n = 11) gr ...[more]

PMID: 27907136

Similar Datasets

Project description:Background:Human visceral leishmaniasis (VL) is a life-threatening protozoan disease caused by parasites belonging to the Leishmania donovani complex. Ethiopia has the highest VL-HIV co-infection rate in the world, with several of these patients presenting with repeated episodes of VL disease (ie, relapse). However, we lack data on how HIV patients with multiple VL relapse present clinically, and whether they continue to respond to currently available medicines. Methods:The medical records of VL-HIV co-infected patients with multiple VL relapses at the Leishmaniasis Treatment and Research Center in Gondar, Ethiopia, between June 2012 and June 2016 were retrieved. Variables on their clinical and laboratory profiles were collected. Descriptive analysis was done to show the characteristics of the VL episodes. Result:A total of 48 VL episodes in 12 patients were identified, the median number of episodes per patient was 5 (interquartile range, 4-8 episodes). The median time to relapse was 5 months (interquartile range, 3-5.5 months). Splenomegaly was present in 47 of the episodes (98%), fever or other accompanying symptoms were present in only 66% (32 out of 48). The median tissue parasite grade at VL diagnosis was 6+ (interquartile range, 5+- 6+). All patients were on antiretroviral therapy. The median duration of treatment per episode was 2 months (interquartile range, 2-2 months). All patients achieved parasitological cure at discharge at each episode. Conclusions:Multiple recurrences of VL diseases were observed in HIV co-infected patients. With recurrent episodes, splenomegaly was found to be the main manifestation, whereas fever was less common. These patients came with recurrence of diseases in <6 months and required prolonged treatment to achieve cure.Further research on prediction, prevention, and better management options for recurrent VL is needed. ORCID ID: https://orcid.org/0000-0002-1410-0454. (Curr Ther Res Clin Exp. 2020; 81:XXX-XXX).

Project description:Chronic disease caused by infections, cancer or autoimmunity can result in profound immune suppression. Immunoregulatory networks are established to prevent tissue damage caused by inflammation. Although these immune checkpoints preserve tissue function, they allow pathogens and tumors to persist, and even expand. Immune checkpoint blockade has recently been successfully employed to treat cancer. This strategy modulates immunoregulatory mechanisms to allow host immune cells to kill or control tumors. However, the utility of this approach for controlling established infections has not been extensively investigated. Here, we examined the potential of modulating glucocorticoid-induced TNF receptor-related protein (GITR) on T cells to improve anti-parasitic immunity in blood and spleen tissue from visceral leishmaniasis (VL) patients infected with Leishmania donovani. We found little effect on parasite growth or parasite-specific IFN? production. However, this treatment reversed the improved anti-parasitic immunity achieved by IL-10 signaling blockade. Further investigations using an experimental VL model caused by infection of C57BL/6 mice with L. donovani revealed that this negative effect was prominent in the liver, dependent on parasite burden and associated with an accumulation of Th1 cells expressing high levels of KLRG-1. Nevertheless, combined anti-IL-10 and anti-GITR mAb treatment could improve anti-parasitic immunity when used with sub-optimal doses of anti-parasitic drug. However, additional studies with VL patient samples indicated that targeting GITR had no overall benefit over IL-10 signaling blockade alone at improving anti-parasitic immune responses, even with drug treatment cover. These findings identify several important factors that influence the effectiveness of immune modulation, including parasite burden, target tissue and the use of anti-parasitic drug. Critically, these results also highlight potential negative effects of combining different immune modulation strategies.

Project description:BackgroundVisceral leishmaniasis (VL) is severe and potentially fatal. Brazil is one of the countries with the greatest endemicity for the disease in the world. The reduction of CD4+ T lymphocytes, B cells activation and high levels of inflammatory cytokines (IL-6/IL-8/TNF/IL-1β), plasma LPS, soluble CD14, anti-Leishmania IgG3 and low leptin levels are involved in the immunopathogenesis of VL, most associated with severe VL. Despite relapses occurring in about 4-5% of patients with VL not associated with HIV infection, the factors underlying relapses are little known. Our aim was to identify clinical, laboratory and immunological parameters that may be associated with recurrences in VL.MethodsFifteen VL patients recruited from Hospital Eduardo de Menezes (BH-MG) were grouped into relapsing (R-VL, n = 5) and non-relapsing (NR-VL, n = 10) and evaluated during active disease, immediately after treatment (post-treatment) and 6 months post-treatment (6mpt). Clinical and laboratory data obtained from medical records were correlated with CD4+ and CD8+ T cell counts and anti-Leishmania Igs and IL-6 plasma levels and compared to those parameters of ten healthy controls.ResultsDuring the active phase of VL, despite similarity in the clinical symptoms, the rates of thrombocytopenia, elevated transaminases (AST and ALT) and hyperbilirubinemia were higher in the NR-VL group compared to R-VL (p < 0.05), a profile reversed during the post-treatment phase. All patients had low CD4+ T counts in active phase, however, NR-VL patients had a higher gain of this cell type than R-VL in the post-treatment (p < 0.05). There was a significant reduction in IgG3 levels during the follow-up in the NR-VL group compared to the R-VL, especially at 6mpt (p < 0.05). In addition, IgG3 levels were negatively correlated with CD4+ T counts in the R-VL group (r = - 0.52). Elevated levels of IL-6 were observed in active VL and correlated with clinical markers of severity.ConclusionsDuring active phase of VL, the NR-VL patients presented more severe laboratorial abnormalities compared to R-VL, probably because the latter had already received previous treatment. On the other hand, R-VL exhibited greater impairment of immune reconstitution and a high degree of B lymphocyte activation, which must be a factor that favored relapses.

Dataset Information

Immune Activation and Bacterial Translocation: A Link between Impaired Immune Recovery and Frequent Visceral Leishmaniasis Relapses in HIV-Infected Patients.

Publications

Immune Activation and Bacterial Translocation: A Link between Impaired Immune Recovery and Frequent Visceral Leishmaniasis Relapses in HIV-Infected Patients.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure