Litomosoides sigmodontis: A simple method to infect mice with L3 larvae obtained from the pleural space of recently infected jirds (Meriones unguiculatus)

Dept. of Microbiology and Immunology, Uniformed Services University of the Health Sciences, Bethesda, MD 20814, USA.
Experimental Parasitology (Impact Factor: 1.64). 06/2009; 123(1):95-8. DOI: 10.1016/j.exppara.2009.05.009
Source: PubMed


Litomosoides sigmodontis is a filarial nematode that is used as a mouse model for human filarial infections. The life cycle of L. sigmodontis comprises rodents as definitive hosts and tropical rat mites as alternate hosts. Here, we describe a method of infecting mice with third stage larvae (L3) extracted from the pleural space of recently infected jirds (Meriones unguiculatus). This method enables infection of mice with a known number of L3 larvae without the time-consuming dissection of L3 larvae from mites and results in higher worm recovery and patency rates than conventional methods. Additionally, this method allows for geographical separation of the facility maintaining the L. sigmodontis life cycle from the institution at which mice are infected.

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    • "This infection results in the production of large quantities of parasite-specific IgE beginning at 4 weeks post-infection (Torrero et al., 2010), resulting in sensitization of both mast cells and basophils to parasite antigen (LsAg) through binding of specific IgE to FcER1. L3 stage larvae for infection studies were obtained from the pleural cavity of Mongolian jirds (Meriones unguiculatus, TRS Laboratory Inc., Athens, GA) that had been infected by the bite of infectious mites 4 days earlier as previously described (Hubner et al., 2009). "
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