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F McNeilly

Publications and source records attributed to F McNeilly.

67 records · Page 4Linked to original sources
PubMed1994

Infection of leucocyte cell cultures derived from different species with pig circovirus.

Cultures of leucocyte cells were prepared from pig bone marrow, peripheral blood, lung washings, thymus and lymph nodes. Cell cultures were also prepared from peripheral blood from sheep, cattle and a human. Immunofluorescent (IF) staining of all these cultures, following inoculation with pig circovirus (PCV), detected virus replication in all the cell cultures derived from pigs and in the cell cultures derived from cattle. Virus replication in pig leucocyte cell cultures was confirmed by demonstrating the production of infectious virus. Double immunostaining of PCV infected cells using monoclonal antibodies specific for cell membrane markers indicated infection was confined to monocyte/macrophage cell types. No PCV antigen was detected in T or B cells in infected cell cultures.

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PubMed1991

Biological characterisation of Australian isolates of chicken anaemia agent.

Three Australian isolates of chicken anaemia agent (CAA) resisted treatment at 70 degrees C for 5 min and chloroform treatment. Although minor antigenic differences were detected using monoclonal antibodies to CAA, the Australian isolates were indistinguishable from the reference Cux-1 and Gifu-1 isolates in cross-immunofluorescence and cross-neutralisation tests employing polyclonal chicken antiserums. The Australian viruses were pathogenic for intramuscularly inoculated 1-day-old SPF chicks, but were less pathogenic for 7-day-old chicks. Thus the Australian isolates of CAA did not differ significantly in these properties from previously characterised CAA isolates from other continents.

Anemia↗
PubMed1990

Humoral immune responses in seals infected by phocine distemper virus.

Recently the isolation and characterisation of a morbillivirus which caused high mortality in common seals (Phoca vitulina) in 1988 have been reported. Because of the clinical and pathological similarity of the disease in seals to that of distemper in dogs, the name phocine distemper virus (PDV) has been proposed. There are marked differences in the virus-induced proteins of PDV compared to other morbilliviruses and the humoral immune response of moribund and dead seals to PDV was restricted to some of the internal antigens of PDV, similar to the response described earlier for canine distemper virus infection in dogs.

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PubMedDate not supplied

Effects of chicken anemia agent on lymphokine production and lymphocyte transformation in experimentally infected chickens.

One-day-old chicks with no maternal antibodies to chicken anemia agent (CAA) were inoculated intramuscularly with CAA grown in MDCC-MSB1 cells. A control group of birds from the same source was inoculated intramuscularly with a lysate from uninfected MSB1 cells. Birds were killed at 8, 15, 22, 29, and 43 days postinoculation (PI), and the spleens were removed. Spleen cells were dispersed and stimulated with various concentrations of Concanavalin A (Con A), and lymphocyte transformation responses were determined. Supernatants from Con A-stimulated cultures were assayed for T-cell growth factor (TCGF) and interferon. Decreased lymphocyte transformation and TCGF production were demonstrated at 8 and 15 days PI. This was followed by a stimulation in activities before a return to control levels at 43 days PI. Interferon levels were elevated 8 days after infection. This was followed by a significant decrease in activity compared with controls at 15, 22, and 29 days PI, and a return to control levels by 43 days PI. The results suggest that CAA infection in young chickens can produce a dramatic decrease in immune competence, which, although transitory, is likely to seriously compromise the ability of birds to mount a successful immune response to invading pathogens.

Anemia↗
PubMedDate not supplied

Production and preliminary characterization of monoclonal antibodies to chicken anemia agent.

Mice were immunized with partially purified preparations of the Cux-1 isolate of chicken anemia agent (CAA), and their splenocytes were fused with NSO myeloma cells. Three patterns of staining of CAA-infected cells were recognized when the resulting hybridomas were screened by indirect immunofluorescence (IIF). Hybridomas representative of each staining pattern were cloned, and the monoclonal antibodies (MAbs) were characterized. Type 1 staining was indistinguishable from that produced by polyclonal chicken antisera to CAA. Type 2 staining was confined to large nuclear inclusions. Type 3 staining was predominantly nuclear and granular, and differed from type 1 in being more intense and occurring in a higher proportion of nuclei. Three MAbs producing type 1 staining were predominantly Cux-1-specific by IIF; they also reacted to lower titers with the Gifu-1 isolate but not at all with three other CAA isolates. These MAbs had very slight neutralizing activity against Cux-1. Another MAb giving type 1 staining reacted with all CAA isolates tested to high titers in IIF and neutralization tests. MAbs with type 2 and type 3 staining reacted by IIF with all CAA isolates tested but possessed no neutralizing activity. The availability of MABs to CAA should facilitate development of diagnostic tests for the virus.

Animals↗
PubMedDate not supplied

Development of an enzyme-linked immunosorbent assay to detect serum antibody to chicken anemia agent.

An enzyme-linked immunosorbent assay (ELISA) for the detection of antibodies to chicken anemia agent (CAA) has been developed. This test utilizes a CAA-specific mouse monoclonal antibody to selectively capture virus antigen. Chicken antibodies to CAA bind to the captured antigen and are detected with horseradish peroxidase-labeled anti-chicken immunoglobulin using a conventional indirect ELISA protocol. When 388 chicken sera from specific-pathogen-free and commercial flocks from the United Kingdom, West Germany, the United States and Australia were examined, 98.5% agreement was obtained between the results of the ELISA and the indirect immunofluorescence assay. This ELISA should have worldwide application in testing SPF and commercial chicken flocks for CAA antibodies.

Animals↗
PubMedDate not supplied

Chicken anemia agent in the United States: isolation of the virus and detection of antibody in broiler breeder flocks.

Chicken anemia agent (CAA) was isolated from broiler chickens in Texas with a blue wing or anemia dermatitis-like syndrome. Specific-pathogen-free chicks inoculated with field material developed anemia, and CAA was isolated in MDCC-MSB1 cells from bone marrow and lymphoid tissue from inoculated chicks. One isolate, designated EF88/78/276, was further characterized. Infectivity of EF88/78/276 was resistant to treatment with chloroform and with heat at 70 C for 5 minutes. EF88/78/276 was indistinguishable from the Cux-1 and Gifu-1 isolates of CAA by cross-neutralization tests. Almost all 1-day-old susceptible chicks inoculated intramuscularly with EF88/78/276 developed anemia, but contact-infected chicks did not. Antibody to CAA was detected in broiler breeder flocks from Texas, the Delmarva peninsula, and Alabama.

Anemia↗
PubMedDate not supplied

Characterization of surface markers present on cells infected by chicken anemia virus in experimentally infected chickens.

Specific-pathogen-free chickens were infected with chicken anemia virus (CAV) at 1 day of age and killed after 6 days. Using a double-antibody staining procedure, spleen, thymus, and bone-marrow cells containing CAV antigen were stained for presence of T-cell antigens and chicken major histocompatibility complex (MHC) Class 1 and 2 antigens. The results demonstrated CAV infection of precursor T-cells in the thymus and of mature T-lymphocytes in the spleen. A significant proportion of the cells infected in bone marrow expressed MHC Class 2 antigens but did not exhibit the characteristics of T-lymphocytes. Since CAV grows in MDCC-MSB1 cells, the staining characteristics of these cells were also studied. MSB1 cells possessed all of the characteristics of mature, helper T-lymphocytes.

Animals↗
PubMedDate not supplied

Synergism between chicken anemia virus (CAV) and avian reovirus following dual infection of 1-day-old chicks by a natural route.

One-day-old specific-pathogen-free white leghorn chicks were dually infected with the Cux-1 isolate of chicken anemia virus (CAV) and separate avian reovirus strains (S1133 or Uchida) by an oral route. Fourteen days after inoculation, chicks were bled, and packed cell volumes (PCVs) were determined. Chicks were also weighted and examined for macroscopic changes to the bone marrow, thymus, and bursa of Fabricius. The results obtained following dual inoculation of chicks with CAV and reovirus were compared with results obtained from mock-infected chicks or chicks inoculated with CAV or reovirus alone. Chicks dually infected with CAV and the S1133 reovirus strain had significantly (P < 0.05) lower weight gain and more severe tissue damage than chicks inoculated with either virus alone. In addition, a significant (P < 0.05) reduction in the mean PCV was seen in these dually infected chicks when compared with chicks inoculated with CAV alone. No increase in the severity of the disease signs was observed following dual infection with CAV and reovirus strain Uchida.

Animals↗
PubMedDate not supplied

The identification of an 18,000-molecular-weight antigen specific to big liver and spleen disease.

Big liver and spleen (BLS) disease is an infectious syndrome of broiler breeders that has been serologically diagnosed worldwide with the agar gel immunodiffusion test. Liver homogenate from an affected broiler breeder was used as the antigen source in this study. This paper reports the identification, from liver, of a soluble basic protein antigen (molecular weight 18,000) that is specific to BLS disease. The antigen was partially purified from soluble extract of liver using a two-step fractionation procedure comprising Sephacryl S200 gel filtration and carboxymethyl (CM) cellulose cation exchange. After cation exchange, the partially purified (CM) antigen contained approximately 12 proteins. Immunoblotting was used to identify the single BLS disease-specific antigen. In addition, a polyclonal rabbit antiserum raised to the CM antigen was found to be monospecific to the 18,000-molecular-weight antigen by immunoblotting on the CM antigen. This serum was also of use in specifically detecting intracellular BLS disease antigen in frozen cryostat sections by indirect immunofluorescence.

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