Platelet Rich Plasma as a Potential Therapy for Chronic Toxoplasmosis in Immunocompetent and Immunocompromised Murine Model.

Background: Toxoplasma gondii (T. gondii) is one of the most prevalent parasitic zoonoses worldwide, and the host's immunological state significantly influences its clinical manifestations, which can be potentially fatal in immunocompromised hosts. The unavailability of a vaccine, combined with the considerable toxicity of existing medications, necessitates the urgent search for new therapies or adjunctive techniques, including regenerative and immunomodulatory approaches. Hence, the present study investigated, for the first time, the therapeutic potential of syngeneic platelet rich plasma (PRP) against T. gondii ME49 strain-induced chronic toxoplasmosis in both immunocompetent and immunosuppressed mouse models. Methods: 72 albino mice were divided into two sections, immunocompetent and immunosuppressed. Each section contained six groups: healthy, model, cotrimoxazole (CTZ)-treated, PRP-treated, half-dose of both CTZ and PRP-treated, and full-dose of both CTZ and PRP-treated. Treatment efficacy was assessed via parasitological, histological, immunohistochemical, and immunological analyses. Results: PRP, especially when coadministered with the CTZ, mitigated the consequences of toxoplasmosis by significantly reducing brain cyst counts (p < 0.0001), restoring brain tissue architecture, modulating apoptotic pathways by restoring caspase-3 expression in the brain, and normalizing systemic IFN-γ, TNF-α, and IL-10 cytokine profiles. Conclusions: The findings highlight PRP as an adjunct to the reference treatment, CTZ, for controlling toxoplasmosis in both immunocompetent and immunosuppressed conditions via anti-infective, neuroprotective, and immunomodulatory activities.