Abstract
Human lung fibroblasts develop a cytopathic effect (CPE) when infected with Mycoplasma pneumoniae. This study was designed to determine the relationship between host cell metabolism and the formation of the CPE. Human lung fibroblasts were grown in different serum concentrations, plated at different densities, and grown for different periods of time to alter the metabolic activity of the cells. Deoxyribonucleic acid, ribonucleic acid, and protein syntheses were measured by the ability of the cells to incorporate thymidine, uridine, and leucine, respectively. With each treatment, leucine incorporation remained constant. Thymidine and uridine incorporation was higher when the cells were in high serum, at low cell densities, or grown for 2 or 3 days. The appearance of an observable CPE, which was corroborated with a protein synthesis assay, correlated closely with thymidine and uridine incorporation. A more pronounced CPE was seen when thymidine and uridine incorporation was high. In addition, it was found that the first 2 h after infection by M. pneumoniae were the critical hours in determining whether a CPE would develop. This was accomplished by altering the serum concentration of the culture medium at different times postinfection and thereby altering the metabolism of the fibroblasts. These results demonstrate the importance of the metabolic state of the host cells in studying mycoplasma infections and establish a correlation between the nucleic acid metabolism of the cells and the production of a CPE.
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Selected References
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- Baenziger N. L., Jacobi C. H., Thach R. E. Regulation of protein synthesis during density-dependent growth inhibition of BHK21-13 cells. J Biol Chem. 1974 Jun 10;249(11):3483–3488. [PubMed] [Google Scholar]
- Collier A. M., Clyde W. A., Jr, Denny F. W. Biologic effects of Mycoplasma pneumoniae and other mycoplasmas from man on hamster tracheal organ culture. Proc Soc Exp Biol Med. 1969 Dec;132(3):1153–1158. doi: 10.3181/00379727-132-34385. [DOI] [PubMed] [Google Scholar]
- Eaton M. D., Farnham A. E., Levinthal J. D., Scala A. R. CYTOPATHIC EFFECT OF THE ATYPICAL PNEUMONIA ORGANISM IN CULTURES OF HUMAN TISSUE. J Bacteriol. 1962 Dec;84(6):1330–1337. doi: 10.1128/jb.84.6.1330-1337.1962. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Engelhardt J. A., Gabridge M. G. Effect of squamous metaplasia on infection of hamster trachea organ cultures with Mycoplasma pneumoniae. Infect Immun. 1977 Feb;15(2):647–655. doi: 10.1128/iai.15.2.647-655.1977. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Gabridge M. G., Barden-Stahl Y. D., Polisky R. B., Engelhardt J. A. Differences in the attachment of Mycoplasma pneumoniae cells and membranes to tracheal epithelium. Infect Immun. 1977 Jun;16(3):766–772. doi: 10.1128/iai.16.3.766-772.1977. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Gabridge M. G., Dee Barden Stahl Y. Role of cell-associated pathogen metabolism in infection of tracheal explants by Mycoplasma pneumoniae. Med Microbiol Immunol. 1978 Oct 20;165(3):153–161. doi: 10.1007/BF02123172. [DOI] [PubMed] [Google Scholar]
- Gabridge M. G. Oxygen consumption by trachea organ cultures infected with Mycoplasma pneumoniae. Infect Immun. 1975 Sep;12(3):544–549. doi: 10.1128/iai.12.3.544-549.1975. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Gabridge M. G., Polisky R. B. Intracellular levels of adenosine triphosphate in hamster trachea organ cultures exposed to Mycoplasma pneumoniae cells or membranes. In Vitro. 1977 Aug;13(8):510–516. doi: 10.1007/BF02615144. [DOI] [PubMed] [Google Scholar]
- Gabridge M. G., Polisky R. B. Quantitative reduction of 2,3,4-triphenyl tetrazolium chloride by hamster trachea organ cultures: effects of Mycoplasma pneumoniae cells and membranes. Infect Immun. 1976 Jan;13(1):84–91. doi: 10.1128/iai.13.1.84-91.1976. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Gabridge M. G., Singer S. E., Esposito R. A. Cultivation of mycoplasmas in a modified tissue culture medium. Appl Environ Microbiol. 1976 Jun;31(6):986–989. doi: 10.1128/aem.31.6.986-989.1976. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Gabridge M. G., Taylor-Robinson D., Davies H. A., Dourmashkin R. R. Interaction of Mycoplasma pneumoniae with human lung fibroblasts: characterization of the in vitro model. Infect Immun. 1979 Jul;25(1):446–454. doi: 10.1128/iai.25.1.446-454.1979. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Hu P. C., Collier A. M., Baseman J. B. Alterations in the metabolism of hamster tracheas in organ culture after infection by virulent Mycoplasma pneumoniae. Infect Immun. 1975 Apr;11(4):704–710. doi: 10.1128/iai.11.4.704-710.1975. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Hu P. C., Collier A. M., Baseman J. B. Interaction of virulent Mycoplasma pneumoniae with hamster tracheal organ cultures. Infect Immun. 1976 Jul;14(1):217–224. doi: 10.1128/iai.14.1.217-224.1976. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Ingwall J. S., Morales M. F., Stockdale F. E. Creatine and the control of myosin synthesis in differentiating skeletal muscle. Proc Natl Acad Sci U S A. 1972 Aug;69(8):2250–2253. doi: 10.1073/pnas.69.8.2250. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Jacobs J. P., Jones C. M., Baille J. P. Characteristics of a human diploid cell designated MRC-5. Nature. 1970 Jul 11;227(5254):168–170. doi: 10.1038/227168a0. [DOI] [PubMed] [Google Scholar]
- Larin N. M., Saxby N. V., Buggey D. Quantitative aspects of Mycoplasma pneumoniae-cell relationships in cultures of lung diploid fibroblasts. J Hyg (Lond) 1969 Sep;67(3):375–385. doi: 10.1017/s0022172400041796. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Smith M. L., Buchanan J. M. Nucleotide and pentose synthesis after serum-stimulation of resting 3T6 fibroblasts. J Cell Physiol. 1979 Nov;101(2):293–309. doi: 10.1002/jcp.1041010210. [DOI] [PubMed] [Google Scholar]
- Stanners C. P., Becker H. Control of macromolecular synthesis in proliferating and resting Syrian hamster cells in monolayer culture. I. Ribosome function. J Cell Physiol. 1971 Feb;77(1):31–42. doi: 10.1002/jcp.1040770105. [DOI] [PubMed] [Google Scholar]
- Wiebel F., Baserga R. Early alterations in amino acid pools and protein synthesis of diploid fibroblasts stimulated to synthesize DNA by addition of serum. J Cell Physiol. 1969 Oct;74(2):191–202. doi: 10.1002/jcp.1040740211. [DOI] [PubMed] [Google Scholar]
