Immunotherapy based on Pythium insidiosum mycelia drives a Th1/Th17 response in mice.
Pythium insidiosum is an oomycete that affects mammals, especially humans and horses, causing a difficult-to-treat disease. Typically, surgical interventions associated with antimicrobial therapy, immunotherapy, or both are the preferred treatment choices. PitiumVac® is a therapeutic vaccine prepared from the mycelial mass of P. insidiosum and is used to treat Brazilian equine pythiosis. To better understand how PitiumVac® works, we analyzed the composition of PitiumVac® and the immune response triggered by this immunotherapy in mice. We performed an enzymatic quantification that showed a total glucan content of 21.05% ± 0.94 (α-glucan, 6.37% ± 0.77 and (1,3)(1,6)-β-glucan, 14.68% ± 0.60) and mannose content of 1.39% ± 0.26; the protein content was 0.52 mg ml-1 ± 0.07 mg ml-1. Healthy Swiss mice (n = 3) were subcutaneously preimmunized with one, two, or three shots of PitiumVac®, and immunization promoted a relevant Th1 and Th17 responses compared to nonimmunization of mice. The highest cytokine levels were observed after the third immunization, principally for IFN-γ, IL-17A, IL-6, and IL-10 levels. Results of infected untreated (Pythiosis) and infected treated (Pythiosis + PVAC) mice (n = 3) showed that PitiumVac® reinforces the Th1/Th17 response displayed by untreated mice. The (1,3)(1,6)-β-glucan content can be, at least in part, related to this Th1/Th17 response.
['Tondolo|Juliana S M|JSM|', 'Loreto|Erico S|ES|', 'de Jesus|Francielli P K|FPK|', 'Ledur|Pauline C|PC|', 'Verdi|Camila M|CM|', 'Santurio|Janio M|JM|']
D000818:Animals D016207:Cytokines D005936:Glucans D007114:Immunization D007167:Immunotherapy D051379:Mice D025282:Mycelium D058968:Pythiosis D011775:Pythium D018417:Th1 Cells D058504:Th17 Cells D014612:Vaccines
immunotherapy PitiumVac® pythiosis cytokines