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Biomedical subjects

R L Heberling

Publications and source records attributed to R L Heberling.

At least 73 records · Page 4Linked to original sources
PubMed1977

Squirrel monkey retrovirus: an endogenous virus of a new world primate.

Squirrel monkey retrovirus (SMRV) was isolated by cocultivation of squirrel monkey lung cells with canine cells. 3H-labeled 60-70S SMRV RNA, isolated from virus grown in canine cells, hybridized to the same extent and to the same Cot1/2 value to the DNA of all tissues of all squirrel monkeys tested; Cot1/2 values show that SMRV proviral sequences are present in the low repetitive range. No SMRV proviral sequences were detected in tissues from a variety of other New World monkeys, Old World monkeys, or apes. Murine, feline, bovine, and canine cells also contain no detectable SMRV proviral sequences. Competitive molecular hybridization studies revealed no detectable sequence homology between the 60-70S RNAs of SMRV and Mason-Pfizer virus (MPV). The virion-associated DNA polymerase of SMRV is similar to that of MPV in that it has a molecular weight of approximately 80,000 and prefers magnesium as a divalent cation using oligo(dG)-poly(rC) as primer-template. The virion-associated DNA polymerase of SMRV can be clearly distinguished from those of MPV and the mouse mammary tumor viruses, however, by its preference for manganese as a divalent cation in the presence of high salt.

Animals↗
PubMed1977

Correlation of mixed lymphocyte reactivity and skin graft rejection in nonhuman primates.

One-way mixed lymphocyte culture (MLC) reactivity and skin graft rejection were investigated to assess immune competence and histocompatibility in the baboon, the cebus monkey, and the cotton-topped marmoset. Adequate and comparable cell-mediated immunity was demonstrated. MLN reactions revealed strong histocompatibility differences among the three primate species and stimulating alloantigens for unrelated individuals of each species. Xenogeneic skin grafts survived nine days and allogeneic grafts, an average of 11 days. These systems appear readily applicable for assessing histocompatibility in nonhuman primates.

Animals↗
PubMed1977

E and EAC rosettes in man and nonhuman primates and the effect of thymosin in vitro.

E (erythrocyte) and EAC (erythrocytes coated with antibody and complement) rosettes were quantitated in baboons, cebus monkeys and cotton-topped marmosets. There was poor correlation between E rosette levels and other parameter of T-lymphocyte function. In nonhuman primates, E rosettes were increased in the presence of thymosin fraction V, while human E rosettes were not affected.

Animals↗
PubMed1977

Viral infections of the captive Kenya baboon (Papio cynocephalus): a five-year epidemiologic study of an outdoor colony.

Rectal swabs, throat swabs, fecal samples, tissues, and sera were collected from 334 adult and infant Kenya baboons (Papio cynocephalus) in captivity at this institution over a 5-year period. A total of 4,893 specimens were collected, resulting in the isolation of 582 viral isolates (11.9%). The month of November yielded the lowest isolation rate, while the month of January produced the highest rate. The most commonly isolated viruses in adults and infants were SV6 and SV23, followed by N125, SV15, and SV17 in that order in adults, and SA7, N125, SV15, V340, and SV17 in that order in infants. Nine serotypes, namely enteroviruses SV19, SV42, SA5, A13, and N203, as well as adenoviruses SV15, SV20, SV31, and SV37, were isolated only from adults. Two adenovirus serotypes, SA7 and V340, were recovered predominantly from infants.

Adenoviridae Infections↗
PubMed1976

Oncornavirus-like particles in baboon type C virus-infected chimpanzee lung cells (SFRE:CL-1).

Intracytoplasmic type A particles were observed in a fetal chimpanzee lung culture (SFRE:CL-1) inoculated with type C virus-containing supernatants from a coculture of baboon placenta and SFRE:CL-1 cells. Budding, immature, and mature type C particles were also noted. In thin section, spike-like structures were rarely detected on budding intracytoplasmic type A particles but were occasionally observed on some immature and mature virus particles. Unlike mouse mammary tumor virus or Mason-Pfizer monkey virus, infected SFRE:CL-1 cells contained no eccentric or rodshaped nucleoids.

Animals↗
PubMed1976

Autogenous humoral immunity to baboon xenotropic endogenous type C virus.

A radioimmune precipitation assay was used to evaluate the humoral immune response of baboons (Papio cynocephalus) to their endogenous, xenotropic, type C (M7) virus. Using 125I or [3H]leucine-labeled intact virus preparation, we demonstrated that baboons possess naturally occurring virus-binding antibodies to this virus. Antibody appeared directed against envelope and not internal viral proteins. Immunoglobulins responsible for virus-binding were predominant in the IgG and IgA serum fractions, whereas IgM participated to a minor degree. The biologic activities of these immunoglobulins were investigated by means of a focus reduction assay for virus neutralization with a murine sarcoma virus (M7) pseudotype. We determined that, despite the presence of considerable virus binding, none of the normal baboon sera tested possessed neutralizing activity for M7 virus.

Animals↗
PubMed1976

Poxvirus infection of the baboon (Papio cynocephalus).

Ten serial passages of monkeypox (MPV), vaccinia, variola, and chimpanzeepox (chimp-9) viruses were performed in baboons (Papio cynocephalus) via skin scarification. Comparisons of clinical and virological results indicate that MPV and vaccinia are very closely related and that variola and chimp-9 viruses are identical. These findings suggest that infections of simians with chimp-9 virus resulted from contact with variola virus, the source of which is still unknown. On the other hand, MPV in monkeys may have resulted from contact with recently vaccinated humans, serial passage through simian hosts resulting in the biological alterations that produced MPV.

Animals↗
PubMed1975

Ultrastructure of cleavage stages and preimplantation embryos of the baboon.

The baboon preimplantation stages were examined using light and electron microscopy. Six cases were studied at 2, 3, 4, 5, 7 and 8 days estimated fertilization age. The first 3 specimens were composed of 2, 8 and 24 blastomeres respectively. At 5 days, 30 to 40 cells were counted and more than 60 cells in later stages. Primitive "trophoblast cells" differentiate at 7 days and a crescentic blastocoele appears at 8 days. Shedding of the zona pellucida is not observed in the 7 and 8 day specimens. The preimplantation period is longer in the baboon than in man. C-type viruses are observed in the zona pellucida, in the perivitelline and interblastomeric spaces. Microvilli and caveolae cover ther periphery of the baboon conceptus. As in many other mammals, transformation of the mitochondria, changes in the ribosomes distribution, multivesicular bodies, myelin figures, nucleoli and intranuclear clusters of granules are described in the baboon. Cytoplasmic fibrous strands are not present as in the mouse. Experiments on the influence of hormones and drugs on ultrastructural changes would help to evaluate the importance of biohazards during the early development of primates.

Animals↗
PubMed1975

C-type viruses in chimpanzee (Pan sp.) placentas.

C-type virus particles were observed by electron microscopy in placentas from 7 of 9 chimpanzees (Pan sp.). These viruses were morphologically similar to those observed in placentas of other primates.

Animals↗
PubMed1975

Oncorna-like viruses in baboon prostate tissue.

Oncorna-like virus particles were observed in prostate tissue of 2 of 11 baboons inoculated 3 years previously with a chemical carcinogen. There were no indications, however, of any relationship between the carcinogen and the development of virus particles. Biopsy specimens from the animals showed no evidence of neoplasia, and electron microscopic examination suggested that this virus should be categorized as a B-type oncornavirus.

9,10-Dimethyl-1,2-benzanthracene↗
PubMed1975

Isolation of foamy viruses from baboon (Papio cynocephalus) tissues.

Fourty per cent of baboon kidney cell cultures were found to contain foamy virus contaminants regardless of sex of the animal, source or time of year. The older the animal, however, the higher the incidence. Fifty percent of placentas examined contained foamy virus, with first and second trimester specimens more likely to be positive. Foamy virus isolates from baboon lymphocytes were also more frequent as the age of the animal increased. Freezing and thawing these lymphocytes prevented foamy virus isolation. The foamy virus isolates were identified as types 1, 2, or 3.

Age Factors↗
PubMed1975

A comparative study on the presence of C-type viral particles in placentas from primates and other animals.

C-type particles are found in human, baboon, marmoset, rhesus, patas, and cynomolgus monkeys. A cebus monkey and two chimpanzee placentas have failed thus far to show the presence of these particles. Of the nonprimate tissues examined one mouse and one guinea pig placenta were positive whereas a rabbit placenta was negative. Variations in number of particles present in tissues as well as number of animals of a given species containing particles are noted. The isolation of foamyviruses from placenta cultures makes critical evaluation and interpretation of findings imperative. Several considerations suggest that the presence of foamyviruses is coincidental.

Animals↗
PubMed1975

Biohazards and simian viruses.

Nonhuman primates are extensively used in laboratories as experimental animals. It is necessary, however, to realize that their employment may be dangerous to man and other species of primates, if recognition of their flora and fauna, especially viral, is not considered and if appropriate controls are not followed. Several outbreaks have occurred, resulting in high mortality and morbidity of man and simian. A number of recommendations are provided which, if followed, will minimize the waste of time, money, and life.

Animals↗