Details

Autor(en) / Beteiligte

• Akumtoh, Desmond N.
• Njouendou, Abdel J.
• Metuge, Haelly M.
• Sjoberg, Hanna T.
• Pionnier, Nicolas P.
• Chunda, Valerine C.
• Gandjui, Narcisse Victor T.
• Ndzeshang, Lontum B.
• Fombad, Fanny F.
• Abong, Raphael A.
• Enyong, Peter A.
• Fru-Cho, Jerome
• Esum, Mathias E.
• Ritter, Manuel
• Taylor, Mark J.
• Turner, Joseph D.
• Wanji, Samuel

Titel

Onchocerca ochengi male worms implanted in SCID mice and Gerbil: Relationship between microfilaridermia status of cows, nodular worm viability and fertility and worm survival in the rodents

Ist Teil von

• Experimental parasitology, 2021-10, Vol.229, p.108143-108143, Article 108143

Ort / Verlag

Elsevier Inc

Erscheinungsjahr

2021

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• Current treatment options for onchocerciasis are sub-optimal, prompting research and development of a safe cure (macrofilaricide). Onchocerca ochengi, a parasite of cattle, is used as a close surrogate for the human parasite O. volvulus in a murine model for pre-clinical screening of macrofilaricides. Skin from naturally infected cattle have been used in previous studies as a reliable source of parasite material. However, there is limited knowledge on how source-related factors such as the microfilaridermia status of the cattle, the nodule load and nodular worm viability may affect survival of male O. ochengi worms implanted in the rodent hosts. Such relationships were investigated in this study. Dermal tissue and nodules were obtained from Gudali cattle, dissected and cultured to obtain migrating microfilariae (mf) and male worms. Emerged male worms were implanted into SCID mice and Gerbils (Meriones unguiculatus) and recovery rates were determined upon 42 days post implantation. Finally, nodules were processed for histology and embryogram analyses to assess the nodular worm viability and fertility, respectively. Of the 69 cattle sampled, 24 (34.8%) were mf+ and 45 (65.2%) were mf–. The mean nodule loads were 180.5 ± 117.7 (mf+) and 110.6 ± 102.7 (mf-) (p = 0.0186). The mean male worm harvest from nodules were 76.8 ± 120.3 and 47.2 ± 33.4 (p = 0.2488) for mf+ and mf– cattle, respectively. The number of male worms per 100 nodules were 57/100 and 46/100 nodules for mf+ and mf– cows, respectively. Female worms from nodules of mf– cows had higher counts of both normal and abnormal embryos with higher proportions of dead nodular worms evinced by histology compared to those from mf+ cows. A total of 651 worms were implanted into mice and gerbils, out of which 129 (19.81%) were recovered. Logistic regression analysis indicated that the microfilaridermia status of the cattle (presence of mf) (OR = 4.3319; P = 0.001) is the single most important predictor of the success of male worm recovery after implantation into rodents. Microfilaridermic cattle provide a promising source of adult O. ochengi. Male worms from this group of cattle have a better success rate of survival in a murine implant model. Nevertheless, in the programmatic point of view, amicrofilaridermic Gudali cattle would still constitute an important source of O. ochengi male worms with relatively good viability after implantation into rodents. [Display omitted] •There is a need of developing safe macrofilaricide for human onchocerciasis using cattle Onchocerca ochengi.•Skin from naturally infected cattle have been used as a reliable parasite source for development of murine pre-clinical screening models.•The role of source-related factors on O. ochengi production and the success of pre-clinical screening models is assessed.•Worms from positive microfilaridermic cattle are successfully recovered after their implantation into rodents.