Investigation of in Vitro Culturing Method for Ascaris lumbricoides Eggs in Laboratory: From Soil to Bench

Abstract

Background: Ascaris lumbricoides is one of the four most common soil transmitted helminths (STHs), they are transmitted by direct contact with infective eggs present in the contaminated soil. Ascariasis infection causes bowel obstruction, nausea, and vomiting. Investigation of in vitro culturing of Ascaris eggs in laboratory in not routinely reported in the literature, if a simple method could be developed, it can help in testing novel drug discovery for STHs. Hence, this study was carried out to investigate on the in vitro culturing method for Ascaris lumbricoides eggs isolated from soil samples. The eggs of Ascaris lumbricoides were isolated from soil samples in Kampung Orang Asli Sungai Lalang Baru, an indigenous village in Malaysia. Methods:The eggs were primarily isolated from soil using floatation technique. Next, the Ascaris lumbricoides eggs were cultivated using 0.1% of sulphuric acid in a glass petri dish. Then, the petri dish was incubated at 37°C in the incubator. The embryonation of the parasite was observed daily by screening samples under a light microscope. Embryonation of Ascaris eggs was detected in loamy soil within 2-5 days and continued to observe up to 28 days. Results: The result showed four stages of Ascaris lumbricoides eggs from the first-cell stage until the embryonation stage over the time. At the embryonation stage, the larvae of Ascaris worm could be observed. This indicated that the eggs managed to survive and developed in the presence of an acidic environment. Conclusion: It was found that 0.1% sulphuric acid was ideal for the development of Ascaris lumbricoides eggs for cultivating in vitro condition. In future, this method could be used to propagate the eggs for testing anthelminthic drug inhibiting the developmental stages.