Validation of a death assay for Angiostrongylus cantonensis larvae (L3) using propidium iodide in a rat model (Rattus norvegicus)

Authors

Susan I. Jarvi, University of Hawaii at HiloFollow
John Jacob, University of Hawaii at Hilo
Robert T. Sugihara, USDA APHIS Wildlife ServicesFollow
Israel L. Leinbach, USDA APHIS Wildlife Services
Ina H. Klasner, University of Hawaii at Hilo
Lisa M. Kaluna, University of Hawaii at Hilo
Kirsten A. Snook, University of Hawaii at Hilo
M. Kathleen Howe, University of Hawaii at Hilo
Steven H. Jacquier, University of Hawaii at Hilo
Ingo Lange, University of Hawaii at Hilo
Abigail L. Atkinson, University of Hawaii at Hilo
Ashley R. Deane, University of Otago
Chris N. Niebuhr, USDA APHIS Wildlife Services
Shane R. Siers, USDA APHIS Wildlife ServicesFollow

ORCID IDs

https://orcid.org/0000-0002-9824-0509

Date of this Version

7-31-2019

Citation

Jarvi, S.I., J. Jacob, R.T. Sugihara, I.L. Leinbach, I.H. Klasner, L.M. Kaluna, K.A. Snook, M.K. Howe, S.H. Jacquier, I. Lange, A.L. Atkinson, A.R. Deane, C.N. Niebuhr, and S.R. Siers. 2019. Validation of a death assay for Angiostrongylus cantonensis larvae (L3) using propidium iodide in a rat model (Rattus norvegicus). Parasitology 146(11):1421-1428. doi: 10.1017/S0031182019000908

Abstract

Angiostrongylus cantonensis is a pathogenic nematode and the cause of neuroangiostrongyliasis, an eosinophilic meningitis more commonly known as rat lungworm disease. Transmission is thought to be primarily due to ingestion of infective third stage larvae (L3) in gastropods, on produce, or in contaminated water. The gold standard to determine the effects of physical and chemical treatments on the infectivity of A. cantonensis L3 larvae is to infect rodents with treated L3 larvae and monitor for infection, but animal studies are laborious and expensive and also raise ethical concerns. This study demonstrates propidium iodide (PI) to be a reliable marker of parasite death and loss of infective potential without adversely affecting the development and future reproduction of live A. cantonensis larvae. PI staining allows evaluation of the efficacy of test substances in vitro, an improvement upon the use of lack of motility as an indicator of death. Some potential applications of this assay include determining the effectiveness of various anthelmintics, vegetable washes, electromagnetic radiation and other treatments intended to kill larvae in the prevention and treatment of neuroangiostrongyliasis.