:: Farmabrasilis Português Inglês Home | Site Map | Add to Favorites Link | Send page to a Friend | Contact us
Site Search
Notícias

01/07/2014

P-MAPA against visceral leishmaniasis


Two studies in dogs naturally infected by Leishmania sp published in Acta Tropica and International Immunopharmacology reveal the potential of P-MAPA as imune-based therapy for treatment of visceral leishmaniasis.


See the abstracts and download the scientific papers by the links provided  below.


1. Acta tropica   (PDF files)



1. Improvement in clinical signs and cellular immunity of dogs with visceral leishmaniasis using the immunomodulator P-MAPA


Abstract 


This study investigated the immunotherapeutic potential of the protein aggregate magnesium-ammonium phospholinoleate-palmitoleate anhydride immuno-modulator (P-MAPA) on canine visceral leishmaniasis.


Twenty mongrel dogs presenting clinical symptoms compatible with leishmaniasis and diagnosis confirmed by the detection of anti-Leishmania antibodies were studied.


Ten dogs received 15 doses of the immunomodulator (2.0 mg/kg) intramuscularly, and 10 received saline as a placebo. Skin and peripheral blood samples were collected following administration of the immunomodulator.


The groups were followed to observe for clinical signals of remission; parasite load in the skin biopsies using real-time PCR, the cytokines IL-2, IL-10 and IFN-γ in the supernatant of peripheral blood mononuclear cells stimulated in vitro with either total promastigote antigen or phytohemagglutinin measured by capture ELISA, and changes in CD4+ and CD8+ T cell subpopulations evaluated by flow cytometry.


Results


Comparison between the groups showed that treatment with the immunomodulator promoted improvement in clinical signs and a significant reduction in parasite load in the skin. In peripheral blood mononuclear cell cultures, supernatants showed a decrease in IL-10 levels and an increase in IL-2 and IFN-γ.


An increase in CD8+ T cells was observed in peripheral blood. In addition, the in vitro leishmanicidal action of P-MAPA was investigated using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and no leishmanicidal activity was detected.


Conclusions


These findings suggest that P-MAPA has potential as an immunotherapeutic drug in canine visceral leishmaniasis, since it assists in reestablishing partial immunocompetence of infected dogs.



2. International Immunopharmacology (PDF files)


2. Effects of P-MAPA immunomodulator on Toll-like receptor 2, ROS, nitric oxide, MAPKp38 and IKK in PBMC and macrophages from dogs with visceral leishmaniasis


Abstract


Leishmania chagasi is the etiologic agent of visceral leishmaniasis (VL) that can be transmitted to humans and dogs. VL in Brazil represents a serious public health problem; therefore, it is important to study new alternatives to treat infected dogs. In dogs, the therapeutic arsenal against canine VL is limited.


The immunomodulator protein aggregate magnesium-ammonium phospholinoleate-palmitoleate anhydride (P-MAPA) improves immunocompetence when the immune system is impaired, but its dependence on Toll-like receptors (TLRs) and the mechanisms involved in immune response remain unclear.


The in vitro action of P-MAPA on the expression of TLR2 and TLR4, reactive oxygen species (ROS), nitric oxide (NO) and p38 mitogen-activated protein kinase (p38 MAPK) and IKK phosphorylation was studied in mononuclear cells from peripheral blood and macrophages from healthy and Leishmania-infected dogs. The PBMC or macrophages were isolated and cultured with different concentrations of P-MAPA (20,100 and 200 μg/ml) in a humid environment at 37 °C with 5% CO2.


Results


Observation revealed that Leishmania-infected dogs showed a decrease in TLR2 in macrophages compared with healthy dogs and in induction with P-MAPA. ROS were increased in PBMCs from Leishmania spp.-infected dogs compared with healthy dogs and P-MAPA improved ROS production. NO production was increased in culture supernatant from macrophages stimulated by P-MAPA in both healthy and Leishmania sp. infected dogs.


Conclusions


Observation revealed that Leishmania-infected dogs showed a decrease in TLR2 in macrophages compared with healthy dogs and in induction with P-MAPA. ROS were increased in PBMCs from Leishmania spp.-infected dogs compared with healthy dogs and P-MAPA improved ROS production. NO production was increased in culture supernatant from macrophages stimulated by P-MAPA in both healthy and Leishmania spp. infected dogs.


Treatment of macrophages from healthy dogs with immunomodulatory P-MAPA induced p38 MAPK and IKK phosphorylation, suggesting signal transduction by this pathway. Taken togheter these findings suggest that P-MAPA has great potential as immune-based therapy for treatment of visceral leishmaniasis.



Read more: Exploring an one health approach for treatment of leishmaniasis 


Send to a Friend Send to a Friend Print Print Back Back
Lógica Digital
Privacy Policy  |  Legal  |  [email protected] all rights reserved