en |
Characterisation of the vascular pathology in Sigmodon hispidus (Rodentia: Cricetidae) following experimental infection with Angiostrongylus costaricensis (Nematoda: Metastrongylidae)
Vasconcelos, Danielle Ingrid Bezerra de; Mota, Ester Maria & Pelajo-Machado, Marcelo
Abstract
BACKGROUND Angiostrongylus costaricensis is a nematode that causes human abdominal angiostrongyliasis, a disease found
mainly in Latin American countries and particularly in Brazil and Costa Rica. Its life cycle involves exploitation of both
invertebrate and vertebrate hosts. Its natural reservoir is a vertebrate host, the cotton rat Sigmodon hispidus. The adult worms
live in the ileo-colic branches of the upper mesenteric artery of S. hispidus, causing periarteritis. However, there is a lack of data
on the development of vasculitis in the course of infection.
OBJECTIVE To describe the histopathology of vascular lesions in S. hispidus following infection with A. costaricensis.
METHODS Twenty-one S. hispidus were euthanised at 30, 50, 90 and 114 days post-infection (dpi), and guts and mesentery
(including the cecal artery) were collected. Tissues were fixed in Carson’s Millonig formalin, histologically processed for
paraffin embedding, sectioned with a rotary microtome, and stained with hematoxylin-eosin, resorcin-fuchsin, Perls, Sirius Red
(pH = 10.2), Congo Red, and Azan trichrome for brightfield microscopy analysis.
FINDINGS At 30 and 50 dpi, live eggs and larvae were present inside the vasa vasorum of the cecal artery, leading to eosinophil
infiltrates throughout the vessel adventitia and promoting centripetal vasculitis with disruption of the elastic layers. Disease
severity increased at 90 and 114 dpi, when many worms had died and the intensity of the vascular lesions was greatest, with
intimal alterations, thrombus formation, iron accumulation, and atherosclerosis.
CONCLUSION In addition to abdominal angiostrongyliasis, our data suggest that this model could be very useful for autoimune
vasculitis and atherosclerosis studies.
Keywords
Angiostrongylus costaricensis; abdominal angiostrongyliasis; sigmodontinae; arteritis; atherosclerosis
|