Continuous Monkey Kidney Cell Research Articles

Comparison of different cell lines and incubation times in the isolation by the shell vial culture of human metapneumovirus from pediatric respiratory samples

We report a prospective study concerning the efficacy of LLC-MK2 (continuous monkey kidney cell), Hep-2, MDCK (Madin–Darby Canine Kidney), Vero and MRC-5 cell lines, by shell vial assay, and incubation time in the isolation of hMPV from pediatric respiratory samples. The overall sensitivity of the cell lines studied were: 100% for the LLC-MK2, 68.7% for the Hep-2, 28.1% for the Vero, 3.1% for the MDCK and 0% for the MRC-5. Only one strain (3.1%) showed growth in the four cell lines studied and 10 (31.2%) strains only grew in the LLC-MK2 cell line. The analysis of incubation times showed that only 14 strains (43.7%) were able to grow after 3 days of incubation, while all strains (100%) showed growth after 5 days. The use of shell vials with commercial LLC-MK2 cells could be a method for isolating hMPV from respiratory samples in the pediatric population.

Increased sensitivity of antithymocyte globulin-treated newborn rat assay for metastasis

Tumorigenic and metastatic abilities of FL, transformed human amnion, Vero and LLC-MK 2, continuous monkey kidney cell lines (CCLs), none of which produced lung metastases in nude mice, were studied in ATG-treated newborn Wistar rats. Effects of subcutaneous (s.c.) and intraperitoneal (i.p.) inoculation of 10 6 and 10 7 cells were compared. l.p. inoculation of the same number of FL cells produced larger primary tumors, increased incidence of lung metastasis and more metastases per rat than s.c. inoculation. The same was true of the higher inocula administered by either route as compared to the smaller inocula. The CCLs (Vero at passages 320 and 323, LLC-MK 2 at passage 306) inoculated either s.c. or i.p. induced small tumors regressing in all animals. After s.c. inoculation of 10 6 Vero or LLC-MK 2 cells lung metastases did not develop in any rats, but 10 7 inoculum and i.p. administration of both size inocula caused single lung metastases. Thus, increased sensitivity of the rat system was achieved by larger size of the s.c. inoculum or the i.p. route of inoculation. Highly sensitive assay is especially important for evaluation of possible metastatic abilities of CCLs.

Serial propagation of porcine group C rotavirus (pararotavirus) in a continuous cell line and characterization of the passaged virus.

The Cowden strain of porcine group C rotavirus (pararotavirus) was adapted to serial passage in a continuous monkey kidney cell line (MA104). Key factors in its successful adaptation included use of virus passaged in primary porcine kidney cells as the initial inoculum, use of roller tubes, and addition of pancreatin to the maintenance medium. A cell culture immunofluorescence test was used to quantitate the virus at each passage level, since a possible cytopathic effect was obscured by the effects of pancreatin. The virus titers dropped after initial passage into MA104 cells but increased thereafter, with peak titers evident after 16 passages (10(7) immunofluorescence U/ml). Immune electron microscopy and genome electropherotyping were used to identify group C rotavirus particles and confirm group C rotavirus double-stranded RNA gel migration patterns, respectively, from infected cell culture supernatants. The electropherotype of the cell culture-propagated group C rotavirus was identical to that of the gut virulent virus from which it was derived. The cell culture-passaged group C rotavirus also retained its infectivity for gnotobiotic pigs. No group A rotavirus was detected in the intestinal contents of the pigs or in cell culture fluids from group C rotavirus-inoculated monolayers with the two former techniques or the cell culture immunofluorescence test. This is the first verified report of serial propagation of a non-group A rotavirus in a continuous cell line.

Heterotransplantation studies with tissue culture cell lines in various animal and in vitro host systems

The human amnion cell line FL was found to be more tumorigenic than HeLa cells when used as a positive control in heterotransplantation assays. FL cells formed significantly larger locally invasive tumors than HeLa cells in both Balb/c/nu/nu mice and ATG-treated newborn Wistar rats. In addition, FL cells resulted in metastatic growths in the lungs of two of 12 mice six weeks and in 10 of 36 rats three weeks after inoculation. HeLa cells did not produce metastases in either mice or rats. Both these cell lines were obtained from the American Type Culture Collection. Heterotransplantation experiments with a variety of animal host systems confirmed previous findings that newborn Wistar rats treated with rat ATG were the most sensitive to tumor growth. Vero and LLC-MK2 continuous monkey kidney cells formed small, non-progressively growing tumors showing tubule formation and occasional mitoses. LLC-MK2 cells were found to be more pleomorphic in appearance and with more mitoses than Vero cells but neither cell line showed any evidence of distant metastatic growth in any of several organs examined. The human lymphoblastoid cell line Namalwa produced large invasive tumors at the inoculation site but no distant metastases. In the chick embryo skin test it was found that MI values (mitotic index--percentage of cells in mitosis) gave more reproducible results and were less time-consuming than counting mean mitoses per section. Significant differences were found between Vero, LLC-MK2, HeLa and FL cells with Vero giving the lowest and FL the highest values. The use of MI values enhanced the sensitivity of the chick embryo skin test which was found to be a rapid and valuable screening test for tumorigenicity.

Rubella virus identification in primary and continuous monkey kidney cell cultures by immunoperoxidase technique.

Immunoperoxidase technique was applied to identification of rubella virus isolated from clinical specimens in monkey kidney cell cultures. Findings were confirmed by neutralization tests and by the indirect fluorescent antibody technique.

Visna virus-induced fusion of continous simian kidney cells.

Syncytium formation was observed in four continuous monkey kidney cell lines (BS-C-1, VERO, LLC, MK2 and CV-1) after inoculation with visna virus at high multiplicity. Visna virus-induced cell fusion occurred most rapidly and extensively in BS-C-1 and VERO cells; it was least prominent in CV-1 cells. No evidence of significant visna virus multiplication was detected in any of the four monkey kidney cell lines. BS-C-1 cells were successfully used as an indicator cell line in a visna virus plaque assay.

Morphogenesis of a Virus Isolated from a Human with Myelomonocytic Leukemia

A virus has been isolated in tissue culture by co-cultivation in vitro of peripheral leukocytes from a leukemic donor with monkey kidney cells. This virus contains ribonucleic acid, its density is similar to that of members of the oncorna virus group, and its replication is inhibited by Actinomycin D; it is presumably a human oncornavirus. The virus has been detected by electron microscopy both in the peripheral leukocytes of the leukemic donor and in tissue cultures of the continuous monkey kidney cell line originally co-cultivated with these peripheral leukocytes. Plasma from the leukemic donor reacts in indirect immunofluorescence tests with the infected tissue cultures but not with non-infected controls. More recently, infection of a continuous human cell line (FL) has been detected by electron microscopy. Appropriate cell controls are negative.

Studies on Isolation of Variola Virus in a Continuous Monkey Kidney Cell Cultures, and some Properties of the Isolated Virus

Studies on Isolation of Variola Virus in a Continuous Monkey Kidney Cell Cultures, and some Properties of the Isolated Virus

Properties of monkey pox virus.

Certain biological and physiological properties of MPV are reported. Host range was found to include primary monkey, bovine, and rabbit kidney and human amnion and continuous lines of these and several other cells. In continuous monkey kidney cell line kappa (more susceptible than other cells tested) approximately 85% of the virus was adsorbed to the cells in two hours. In these cells CAV was demonstrated 12 hours p.i. and maximal yield obtained in 48 hours. The maximal titer of free virus (obtained 96 hours p.i.) was roughly 1% of that of CAV.