Cryptosporidium life cycle and development: New insights
Panagiotis Karanis
Qinghai University, China
: J Immunol Tech Infect Dis
Abstract
Cryptosporidium is an important ubiquitous pathogen for a wide range of vertebrates, including humans, and has a great global impact. There are developments in the axenic in vitro culture of Cryptosporidium. Systematically experimental findings regarding the life cycle of the parasite and developmental biology, mainly including the physiological in vitro conditions reveals in new insights and increasing of our knowledge of this important pathogen. Various culture media were assessed for the axenic cultivation of C. parvum, genotype II. After pre-trials, the most promising media have been modified using various supplements and different culture conditions. Different developmental stages were observed in high numbers and microscopically documented. After tuning the medium with supplements, the yield of parasitic developmental stages increased indicating that the modified media might ultimately enable the long-term cultivation of Cryptosporidium in axenic cell-free culture. The asexual, sexual stages and new developed oocysts of C. parvum were confirmed using transmission electron microscopy (TEM). The asexual reproduction of C. parvum was fit to the pattern of development of both eimerian coccidian and neo-gregarines. Further novel findings are the visualization of the asexual Cryptosporidium stages developing within the oocysts and the extension of the outer membrane of some of the developmental stages, as parasitophorous vacuolelike membranes were also evident. The unique cell-free development of C. parvum, along with establishment of meronts and merozoite formation, is the first evidence described at the ultra-structural level. Sexual development was extremely rapid after inoculation of oocysts into the medium. The process began within ½-12 h and was completed with new oocysts formation 120 h post-inoculation. The ultrastructural data present for the first time the exogenous development of Cryptosporidium parvum, examined in in vitro cell-free culture using TEM.
Biography
Panagiotis Karanis has completed his Ph.D at the age of 31 years from Bonn University and postdoctoral studies from Bonn University School of Medicine. He is the director of the Center for Biomedicine and Infectious Diseases at Qinghai University, China. He has published more than 90 papers in reputed journals on parasitic and infectious diseases. panagiotis.
E mail: karanis@uk-koeln.de
