Development of Onchocerca volvulus in humanized NSG mice and detection of parasite biomarkers in urine and serum

Patton, John B.; Bennuru, Sasisekhar; Eberhard, Mark L.; Hess, Jessica A.; Torigian, April; Lustigman, Sara; Nutman, Thomas B.; Abraham, David

Both the anterior and posterior ends in both sexes were bluntly rounded and only slightly tapered (Fig 3A, 3B and 3F ). Other than growth in length, the major change from L3 was development of the reproductive systems. In the L3, both the female and male systems are rudimentary genital primordia consisting of only several cells. In the 8-12-week old worms, the female ovejector had formed and had attached to the body wall. The ovejector was ovoid in shape, relatively large and filled the body cavity, and had a distinct lumen (Fig 3C and 3D) . Rudimentary cellular growth of the reproductive tubes was also evident (Fig 3D) . In males, the testis, located at approximately mid-body, had become elongate in shape and had looped posteriorly to form a classic shepherd's crook (Fig 3E) . In addition, the spicule pads were well developed and demarcated (Fig 3F) but were still oval in shape and had not yet started to take on the shape of the spicules nor was there any evidence of cuticularization. These observations are consistent with parasite development into advanced fourth stage larvae (L4).