Natural expression of feline type-C virus genomes. Prevalence of detectable FeLV and RD-114 GS antigen, type-C particles and infectious virus in postnatal and fetal cats

✍ Scribed by Murray B. Gardner; Suraiya Rasheed; Robert W. Rongey; Howard P. Charman; Barbara Alena; Raymond V. Gilden; Robert J. Huebner

• Publisher: John Wiley and Sons
• Year: 1974
• Tongue: French
• Weight: 671 KB
• Volume: 14
• Category: Article
• ISSN: 0020-7136
• DOI: 10.1002/ijc.2910140112

✦ Synopsis

Abstract

The group‐specific (gs) antigen of RD‐114, an endogenous type‐C virus of domestic cats, was detected by complement fixation (CF) in two of 100 fetal cats and was not detected in any tumors or spleens of postnatal cats. RD‐114 virus was isolated in vitro in RD human sarcoma cells from two of 31 normal cat fetuses but not from any postnatal cat tumors or spleens, with one exception. Feline leukemia virus (FeLV) gs antigen was detected by CF and type‐C particles were seen by electron microscopy (EM) in high prevalence in young cats with lymphoma (65%), anemia (75%) and infectious peritonitis (25%). FeLV gs antigen, type‐C particles and infectious FeLV were occasionally (10‐20%) found in cat fetuses. The general absence of FeLV gs antigen in the endometrium of pregnant cats and the low prevalence of detectable FeLV gs antigen in cat fetuses suggest that the epigenetic transplacental spread of infectious FeLV is not a common occurrence in domestic cats. However, the isolation of FeLV from two pairs of fetal littermates and from the endometria and spleens of both mother cats indicates that such an epigenetic transmission of FeLV can occasionally occur. There was an excellent correlation between detection of RD‐114 and FeLV gs antigen by CF tests in fetal and postnatal tissues and the subsequent isolation in vitro of the corresponding virus. In lymphoma‐ and carcinoma‐bearing cats over 10 years of age, FeLV gs antigen, type‐C particles and infectious virus were seldom found. RD‐114 and FeLV gs antigens or infectious virus were never detected in the same tissues, the same cat or the same litter. These findings are discussed in relation to the natural history of these two different feline type‐C virus genomes.