TY - JOUR
T1 - Detection of ovine lentivirus in seronegative sheep by in situ hybridization, PCR, and cocultivation with susceptible cells
AU - Johnson, L. K.
AU - Meyer, A. L.
AU - Zink, M. C.
N1 - Funding Information:
We thank Randy Irwin for assisting in the testing of the sheep, Jeff Spelman and Darlene Sheffer for technical assistance, Maryann Brooks for typing assistance and 0. Narayan for critical evaluation of the manuscrint. This studv was funded bv NIH Grants NS28357-
PY - 1992/12
Y1 - 1992/12
N2 - Serological surveys for ovine lentivirus (OvLV), a world-wide cause of pneumonia and chronic debilitation in sheep, have demonstrated a wide range of seroprevalence rates. This study analyzed OvLV infection in a purebred sheep flock with a history of OvLV disease (flock 1), and compared the prevalence with that of a flock lacking previous OvLV-associated disease (flock 2). Serological tests (ELISA and Western blot assay) indicated that 25% of sheep of all ages in flock 1 (Group A) and 33% of animals of all ages in flock 2 (Group B) had antibodies to OvLV. In situ hybridization, however, detected viral RNA in a much larger proportion of sheep (72 and 67%, respectively). Animals less than 1 year of age rarely had antibodies to OvLV, although most harbored viral RNA. Twenty animals in this age group from flock 1 (Group C) were therefore studied more closely for infection. These yearling animals were tested serologically by ELISA and their peripheral blood-derived macrophages were cultured for 14 days to amplify any infection in these target cells. The macrophages were then tested by in situ hybridization, PCR, and cocultivation with susceptible target cells. The results of these tests showed that while only 10% of animals in Group C were seropositive, 70% were positive by in situ hybridization, PCR, and cocultivation. These data suggest that latent OvLV infection is common in sheep and that infection is frequently undetected by serological tests.
AB - Serological surveys for ovine lentivirus (OvLV), a world-wide cause of pneumonia and chronic debilitation in sheep, have demonstrated a wide range of seroprevalence rates. This study analyzed OvLV infection in a purebred sheep flock with a history of OvLV disease (flock 1), and compared the prevalence with that of a flock lacking previous OvLV-associated disease (flock 2). Serological tests (ELISA and Western blot assay) indicated that 25% of sheep of all ages in flock 1 (Group A) and 33% of animals of all ages in flock 2 (Group B) had antibodies to OvLV. In situ hybridization, however, detected viral RNA in a much larger proportion of sheep (72 and 67%, respectively). Animals less than 1 year of age rarely had antibodies to OvLV, although most harbored viral RNA. Twenty animals in this age group from flock 1 (Group C) were therefore studied more closely for infection. These yearling animals were tested serologically by ELISA and their peripheral blood-derived macrophages were cultured for 14 days to amplify any infection in these target cells. The macrophages were then tested by in situ hybridization, PCR, and cocultivation with susceptible target cells. The results of these tests showed that while only 10% of animals in Group C were seropositive, 70% were positive by in situ hybridization, PCR, and cocultivation. These data suggest that latent OvLV infection is common in sheep and that infection is frequently undetected by serological tests.
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U2 - 10.1016/0090-1229(92)90155-H
DO - 10.1016/0090-1229(92)90155-H
M3 - Article
C2 - 1333379
AN - SCOPUS:0026677376
SN - 0090-1229
VL - 65
SP - 254
EP - 260
JO - Clinical Immunology and Immunopathology
JF - Clinical Immunology and Immunopathology
IS - 3
ER -