The pathogenesis of quail bronchitis.

To determine the fate of virus and characterize the development of lesions, 1-week-old bobwhite quails (Colinus virginianus) were inoculated intratracheally with 10(6) mean tissue-culture-infective doses of quail bronchitis virus. Quails were killed and necropsied sequentially at 2, 4, 8, 16, and 24 hours postinoculation (PI) and on days 2-10 PI. Virus was first isolated from the lung as early as 2 hours PI, from cecal tonsils and bursa of Fabricius 4 hours PI, and from spleen and liver 8 hours PI.

Immune function in pheasants experimentally infected with marble spleen disease virus.

Two experiments were conducted to evaluate the effect of marble spleen disease virus (MSDV) infection on the immune response of pheasants. In the first, 15 ring-necked pheasants were inoculated orally with cell-culture-propagated MSDV and 15 received saline (controls). On days 7, 21, and 35 postinoculation (PI), all birds received sheep erythrocytes intravenously.

Detection of type II avian adenoviral antigen in tissue sections using immunohistochemical staining.

An immunohistochemical staining technique for the detection of marble spleen disease (MSD) viral antigens and other type II avian adenoviral antigens was developed using a mixture of monoclonal antibodies produced against hemorrhagic enteritis (HE) virus and a commercial streptavidin-biotin peroxidase indicator system. This technique was applied to both frozen and formalin-fixed paraffin-embedded tissue sections. The immunohistochemical staining technique was used on tissues from pheasants with experimental MSD, on tissues from a pheasant with natural MSD, and on tissues from turkeys with natural HE.

The influence of age on the response of ring-necked pheasants to infection with marble spleen disease virus.

Ring-necked pheasants that were negative for maternal antibody against type II avian adenoviruses were orally inoculated with 5.0 x 10(2) tissues-culture-infective doses of marble spleen disease (MSD) virus at 1-week intervals through 6 weeks of age, and at 9 and 13 weeks of age. Groups of four virus-inoculated birds and two control birds were necropsied at 4, 6, 8, and 10 days postinoculation, and the spleens were evaluated for gross and microscopic lesions.

Identification of Pneumocystis carinii in immunodeficient mice.

Various procedures were utilized to determine the most sensitive, cost and labor effective techniques for detection of Pneumocystis carinii in immunologically compromised mice. Immunoperoxidase staining techniques that utilized polyclonal antibodies directed against purified rat or mouse P. carinii were more sensitive and specific than staining with Gomori's methenamine silver.

Adherence of Pneumocystis carinii in lung cells during in vitro cultivation.

This study describes an approach to cultivation of Pneumocystis carinii (Pc) on 2 cell lines derived from lung (A549, human and L2, rat) with emphasis on the organisms which adhered to the cells. Immunofluorescent staining was used for growth assays.

An indirect fluorescent antibody test for antibodies to transmissible gastroenteritis of swine.

The indirect fluorescent antibody test was modified to provide a rapid technique for the detection, screening and titration of antibodies to transmissible gastroenteritis of pigs. Large numbers of slides containing transmissible gastroenteritis antigen were prepared by planting mixtures of infected and uninfected swine testicular cells onto multiwelled teflon-coated slides. After overnight incubation, about one-half of the cells in each well were infected which provided contrast to aid in detecting specific fluorescence in the presence of varying degrees of background staining.

Neoplasms of Equidae.

In a retrospective study of neoplasms in Equidae pre;ented to the Animal Disease Diagnostic Laboratory, Purdue University, from Jan 1, 1970, to Dec 31, 1974, data were compiled on numbers and anatomic sites of neoplasms as well as on age, sex, and breed of subjects from which the neoplasms were taken. During this 5-year period, 21 neoplasms were diagnosed from 687 equine necropsies (3.1%) and 215 from 635 biopsies (33.

Subacute sclerosing panencephalitis: experimental infection in primates.

Measles virus isolated from the brain of a 12-year-old boy with subacute sclerosing panencephalitis caused a chronic, progressive encephalitis in experimentally infected rhesus monkeys. The infection was eventually fatal in spite of pre-existing measles immunity and a vigorous secondary antibody response in serum and cerebrospinal fluid of the infected animals. The findings provide a basis for studies into the pathogenesis and possible treatment of the human disease.

Hamster brain tumor cells persistently infected with measles-subacute sclerosing panencephalitis virus.

A persistent infection was established in a cell line derived from a hamster brain tumor (HBT) with the HBS strain of measles-subacute sclerosing panencephalitis (SSPE) virus. The persistently infected cells (HBT-M) were studied with regard to their growth in vitro and their transplantability in vivo. Although the growth of the HBT-M cells paralleled that of the HBT cells in vitro their transplantability was decreased in weanling hamsters.

Immune enhancement of the tumorigenicity of hamster brain tumor cells persistently infected with measles virus.

Studies were conducted on the tumorigenicity of a hamster brain tumor (HBT) cell line persistently infected with measles virus (MV). This cell population, termed HBT-M, exhibited decreased tumorigenicity in weanling hamsters when implanted intracutaneously. The lowered tumorigenicity of the HBT-M cells could be counteracted by concurrent hydrocortisone treatment restoring the tumor-producing capacity to levels comparable to those of the highly tumorigenic HBT cells.

Cell-associated subacute sclerosing panencephalitis agent studied in organotypic central nervous system cultures: viral rescue attempts and morphology.

Organotypic cultures of hamster cerebellum were exposed to the IP-3-Ca cell line , which contains a cell-associated subacute sclerosing panencephalitis agent. Central nervous system (CNS) cultures were examined by light and electron microscopy as well as standard virological techniques from 3 to 46 days postinfection. The results indicate that although viral nucleocapsid material was transferred to elements of the CNS, cell-free virus could not be detected by virological techniques and by electron microscopy, and budding viral particles were not observed.

Persistent infection of BSC-1 cells by defective measles virus derived from subacute sclerosing panencephalitis.

A line of cells (IP-3), persistently infected with defective measles virus, was developed from co-cultures of subacute sclerosing panencephalitis-derived brain cells with monkey kidney cells (BSC-1). The line, carried for more than 45 serial passages, produced neither infectious virus nor hemagglutinin. Cultures consistently displayed a cycling focal cytopathic pattern of infection characterized by formation of syncytia, necrosis, and plaques followed by healing.

Diagnosis of transmissible gastroenteritis in pigs by means of immunofluorescence.

THE FLUORESCENT ANTIBODY (FA) TEST FOR THE DIAGNOSIS OF FIELD OUTBREAKS OF TRANSMISSIBLE GASTROENTERITIS (TGE) IN BABY PIGS WAS COMPARED TO OTHER AVAILABLE MEANS INCLUDING: virus isolation by inoculation of test pigs, intestinal lesions especially villous atrophy, and clinical observations. Immunofluorescent tests were done on frozen sections of the small intestine and it was possible to make a specific diagnosis within two hours after collecting samples. The results obtained with the FA test compared favorably with virus isolation from infected tissues.