Establishment of an in vitro culture system to study the developmental biology of Onchocerca volvulus with implications for anti-Onchocerca drug discovery and screening

Background Infections with Onchocerca volvulus nematodes remain a threat in Sub-Saharan Africa after three decades of ivermectin mass drug administration. Despite this effort, there is still an urgent need for understanding the parasite biology especially mating behaviour and nodule formation as well development more potent drugs that can clear developmental (L3, L4, L5) adult stages inhibit reproduction behaviour. Methodology/Principal findings Prior to culture, freshly harvested O . L3 larvae from dissected Simulium damnosum flies were purified by centrifugation using 30% Percoll solution eliminate fly tissue debris contaminants. Parasites cultured both cell-free cell-based co-culture systems monitored daily microscopic visual inspection. Exhausted culture medium was replenished every 2–3 days. The system (DMEM supplemented 10% NCS) supported viability motility up 84 days, while FBS seeded on LLC-MK 2 feeder cells) extended worm survival 315 Co-culture alone promoted two consecutive moults (L3 L4 highest moulting rates (69.2±30%) observed DMEM cells, no moult NCS LEC cells. In male worms attached vulva region female may have mated vitro Apparent early initiation nodulogenesis systems. Conclusions/Significance present study describes which be maintained leading stages. Thus, provide platform investigate stage used additional targets macrofilaricidal screening.