Immunomodulatory dynamics of excretory and secretory products on Th9 immune response during Haemonchus contortus infection in goat

Abstract

CD4+ T cells play critical roles in mediating adaptive immunity to a variety of pathogens. Recently, new subset of CD4+T named as T helper 9 cells that express the prototypical interleukin-9 (IL-9) cytokine have been recognized in human and mice models during different parasitic infections. Haemonchus contortus is a gastrointestinal nematode of small ruminants which cause high mortality in young animals. During infection, Excretory and Secretary Products (ESPs) are released in the host body. No other study has reported yet on immunomodulatory dynamics of H. contortus ESPs on Th9 immune response in vitro or in vivo. In this study, immunomodulatory effects of ESPs (5, 10, 20, 40, 80; μg/mL) incubated with goat PBMCs on Th9 cells, IL-9 immune response and TGF-β/Smad signaling regulator were evaluated in vitro. Moreover, for in vivo study, goats were infected with different doses (P-800, P-2400, and P-8000) of H. contortus infective larva (L3) and immunomodulatory effects on Th9 cells, IL-9 immune response and TGF-β/Smad signaling regulator were evaluated at 7, 10, 14, 18, 21, 28 Days Post Infection (DPI). Flow cytometry was performed to evaluate the effects on Th9 cells and quantitative real time polymerase chain reaction was performed to evaluate the IL-9 cytokine transcription level. Additionally, fecal egg counting was also performed in parallel to confirm the infection. All goats were dewormed at 29 DPI and all experiments were also performed at 35 DPI, one week post deworming. The finding indicated that 10, 20, 40, 80 μg/mL concentration of ESPs incubated with goat PBMCs showed significant increase in the production of Th9 cells, signature cytokine IL-9 and expression of TGF-β/Smad signaling regulator as compared to control group in vitro.All infected groups showed significant increase in production of Th9 cells and IL-9 cytokine and expression of TGF-β/Smad key genes at 18, 21, and 28 DPI as compared to control group. Likewise, at 14 DPI, P-2400 and P-8000 groups showed significant increase in production of Th9 cells, IL-9 cytokine and expression of TGF-β/Smad key genes. While at 10 DPI, production of Th9 cells and IL-9 was significantly

Unveiling the Immunomodulatory Characteristics of Haemonchus contortus Ephrin Domain Containing Protein in the Parasite–Host Interactions

“…The β -actin gene was used as reference gene. According to our previous study [ 7 ], primer sequences presented in Supplementary Materials Table S1 were used in this study.…”

“…As referred to before, flow cytometry was employed to ascertain how markers are expressed on T cells from PBMCs [ 12 , 26 , 27 ]. Varying concentrations of rHcEPH (10, 20, and 40 μg/mL) and PBS (control) were used to culture the goat PBMCs for 48 h. Then, at 37 °C in a humidified atmosphere with 5 percent CO 2 , the incubation of phorbol myristate acetate (50 ng/mL; Sigma, St Louis, MO, USA) and ionomycin (1 μg/mL; Sigma, St Louis, MO, USA) was carried out [ 7 ]. Brefeldin A (10 μg/mL; Sigma, St Louis, MO, USA) was mixed after 3 h of stimulation, and cells were obtained and washed using PBS after 6 h of stimulation.…”

“…Nematodes are known to release ESPs which can enter and survive inside a host by modulating the host immune responses [ 6 ]. Furthermore, ESPs from H. contortus has the ability to increase protective immunity by activating Th9 immune cells in vitro [ 7 ]. It was demonstrated previously that Ephrin domain-containing protein (EPH) from HcESPs from this parasite in various developmental stages [ 8 ].…”

“…Peripheral blood mononuclear cells (PBMCs) are comprised of numerous immune cells, which play essential roles in inherent and adaptable immune reactions. After interacting with different antigen, the naïve CD4 + T helper (Th) cells regulate the adaptive immune system by producing specific cytokines [ 7 , 12 ]. Recent studies illuminated that IL-9 can be secreted by a specialized population of T cells called Th9 cells, which mediate anti-parasite immunity by producing IL-9 [ 13 , 14 , 15 ].…”

“…Th9 cells can produce IL-10 while producing IL-9, but not IL-4, IL-5, IL-13 and other cytokines, which can distinguish Th9 cells from other IL-9 producing cells [ 19 ]. In our previous study, we evaluated the immunomodulatory effects of HcESPs on the differentiation of Th9 cells and IL-9 cytokine production in vitro, which would help to understand the relationship between host and parasite [ 7 ].…”