Rabbit model for mucosal immunity in the bowel: I. establishment of virus‐infected ileal loops

Abstract

An animal model was designed for use in studies of initial cellular immune responses to virus infection of the intestinal mucosa. The animal chosen was the New Zealand White rabbit and the mucosal site the subterminal ileum, isolated in a Thirty-Vella loop. The antigen used was parainfluenzavirus type 3, which would normally be destroyed by bile salts if ingested. Loops approximately 20 cm in length, each containing at least one Peyer's patch, were exteriorised through left paramedian stomata. Atrophic changes began to appear in the loops by 7 days, but no observable diminution in their associated lymphoid tissues was evident. The genesis of parainfluenzavirus type 3 infection in the loops was monitored by assay of sequential loop washings for infectious virus and in fluorescent antibody studies of cells from infected loop epithelia. Infectious virus was recovered for up to 13 days after inoculation and specific intracytoplasmic immunofluorescence was detected in loop epithelial cells. There was little serological evidence of systemic spread of the virus. A localised cellular immune response against parainfluenzavirus type 3 was mounted in the lymphoid tissues associated with the infected loops by day 14, but was not detected in systemic lymphoid tissues. No reactivity was detected in rabbits given inactivated virus via their loops or in those receiving infectious virus intravenously. This model appears to be capable of generating mucosal cellular responses to infection and may therefore be suitable for further studies in this field.

Contamination of a specific-pathogen-free rat breeding colony with Human parainfluenzavirus type 3

“…While the latter includes the type 2 and 4 PIVs, the former possesses type 1 (human hPIV1 and mouse Sendai virus) and type 3 (hPIV3 and bovine PIV3, a causative agent for shipping fever) PIVs. Animals known to be infected with PIV3s other than the human and bovine species include hamster (Craighead et al, 1960), cotton rat (Murphy et al, 1981;Porter et al, 1991), guinea pig (Henricks et al, 1993) and rabbit (Holmes & Ramsay, 1988), but only under laboratory conditions. The nucleic acid similarity of the The GenBank/EMBL/DDBJ accession numbers for the hPIV3 sequences reported in this paper are AB195612 for B12 NP, AB189962 for KK24 NP, AB195610 for KK24 L, AB189960 for KK24 HN, AB195613 for BRD NP, AB195611 for BRD L and AB189961 for BRD HN. open reading frame (ORF) of the HN gene among hPIV3 sequences deposited in GenBank/EMBL/DDBJ is >93 %.…”