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Infection and Immunity Dec 1985Mycoplasma orale, maintained as a contaminant of a mouse hybrid cell line, induces an intense proliferation in short-term culture of lymphoid cells of inbred mice. Cell...
Mycoplasma orale, maintained as a contaminant of a mouse hybrid cell line, induces an intense proliferation in short-term culture of lymphoid cells of inbred mice. Cell division induced by the contaminated cell culture fluid reaches a maximum on day four and declines rapidly thereafter. Culture fluids from hybrid cells freed of contamination do not cause proliferation. Cells from the spleen, bone marrow, and thymus of each of several strains of inbred mice, including xid CBA/N, poorly responsive to lipopolysaccharide, are stimulated by the mitogen, as are cells from BALB/c nude mice. The characteristics of the stimulatory effect are analogous in several important aspects to those of naturally occurring T cell-derived growth factors. In the absence of detectable numbers of T cells, both small and large B lymphocytes undergo mitosis in the presence of contaminated cell culture fluid, and B cells stimulated to divide by lipopolysaccharide are sustained for further rounds of replication by M. orale-containing cell culture fluid. The fluid also augments the stimulatory effect on thymocytes of suboptimum concentrations of phytohemagglutinin mimicking the effect of interleukin-1. Unlike with most naturally occurring lymphoid cell mitogens, however, the dividing cells do not go on to immunoglobulin secretion.
Topics: Animals; Bone Marrow; Cell Division; Cells, Cultured; Culture Media; Interleukin-1; Lymphocyte Activation; Mice; Mice, Inbred Strains; Mycoplasma; Phytohemagglutinins; Spleen; Thymus Gland
PubMed: 3877689
DOI: 10.1128/iai.50.3.636-640.1985 -
Cellular Immunology Jun 1989We and other investigators have previously demonstrated that mycoplasmas induce macrophage-mediated lysis of tumor cells, but the mechanism responsible for this process...
We and other investigators have previously demonstrated that mycoplasmas induce macrophage-mediated lysis of tumor cells, but the mechanism responsible for this process had, thus far, not been clarified. We now report that addition of either viable or heat-killed Mycoplasma orale to murine macrophages induces a cytolytic activity which, due to its neutralization by a specific antiserum against murine cloned recombinant tumor necrosis factor (rTNF), was identified as TNF-mediated. Both thioglycollate-elicited peritoneal macrophages and the normal macrophages cloned from our JBM phi 1.1 bone-marrow-derived cell line effectively produced TNF at levels similar to, or higher than, those obtained in the presence of high concentrations of lipopolysaccharide (LPS). Four other mycoplasma species demonstrated a varied capacity to induce TNF production by macrophages. Elevated TNF levels were also observed during macrophage-mediated cytolysis of murine A9 fibrosarcoma cells in the presence of either M. orale or LPS. Addition of the specific antiserum against rTNF at a concentration which neutralized all TNF activity in the co-cultures partially inhibited concomitant A9 cell killing. We can, therefore, conclude that M. orale induces TNF production which is, at least partially, responsible for subsequent tumor cell killing.
Topics: Animals; Macrophage Activation; Macrophages; Mice; Mycoplasma; Tumor Cells, Cultured; Tumor Necrosis Factor-alpha
PubMed: 2720790
DOI: 10.1016/0008-8749(89)90012-9 -
Acta Pathologica, Microbiologica, Et... Feb 1985The influence of mycoplasma infection on the in vitro invasiveness of S. typhimurium in HEp-2 cell cultures has been tested. Two strains of arginine-utilizing mycoplasma...
The influence of mycoplasma infection on the in vitro invasiveness of S. typhimurium in HEp-2 cell cultures has been tested. Two strains of arginine-utilizing mycoplasma species Mycoplasma hominis and M. orale both seemed to inhibit the bacterial in vitro invasiveness. Both the ratio of infected cells and the number of intracellular bacteria per cell were reduced in the mycoplasma-infected cultures.
Topics: Cells, Cultured; Humans; Microscopy, Electron, Scanning; Mycoplasma Infections; Salmonella typhimurium; Species Specificity
PubMed: 3885679
DOI: 10.1111/j.1699-0463.1985.tb02853.x -
Journal of Bacteriology Nov 1967Mycoplasma strains (B1, B2, CS, and S1A) were isolated from the saliva of normal cats. These were compared with a strain (CO) isolated from the eye of a cat with severe...
Mycoplasma strains (B1, B2, CS, and S1A) were isolated from the saliva of normal cats. These were compared with a strain (CO) isolated from the eye of a cat with severe conjunctivitis. On the basis of morphology, biochemical reactions, and antigenic composition, two distinct species were recognizable. Strains CO, B1, and B2 were antigenically unrelated to the other species tested; strains CS and S1A possessed antigenic components in common with Mycoplasma arthritidis, M. salivarium, M. hominis, type 1, and M. orale, types 1 and 2. It was tentatively suggested that the two cat species be called M. felis and M. gateae, respectively.
Topics: Animals; Antigens; Cats; Chloramphenicol; Complement Fixation Tests; Conjunctivitis; Dihydrostreptomycin Sulfate; Erythromycin; Hemolysis; Immune Sera; Immunodiffusion; Lincomycin; Mycoplasma; Neomycin; Novobiocin; Rats; Saliva; Tetracycline
PubMed: 4168314
DOI: 10.1128/jb.94.5.1451-1458.1967 -
Physiological Chemistry and Physics and... 1992Lipid composition of Mycoplasma orale was examined and compared with that of horse serum added to the growth medium. Ratios of cholesterol/cholesterol ester and... (Comparative Study)
Comparative Study
Lipid composition of Mycoplasma orale was examined and compared with that of horse serum added to the growth medium. Ratios of cholesterol/cholesterol ester and sphingomyelin/phosphatidylcholine were much higher in M. orale than in the horse serum, indicating the organism incorporates selectively cholesterol and sphingomyelin. A distinct difference between the lipids from the two sources was that in phospholipids of M. orale almost all (greater than 95%) of the fatty acyl residues were saturated whereas nearly half of the residues were unsaturated in horse serum phospholipids. Approximately one third of M. orale phospholipids was phosphatidylglycerol, which was synthesized by the organism as was demonstrated by 32P-labeling experiment. Its acyl residues consisted mainly of C16:0 and were efficiently labeled with 14C-palmitate but not with 14C-acetate. These results clearly indicate the de novo synthesis of phosphatidylglycerol by M. orale is through acylation with exogenous saturated fatty acids. On the other hand, all the phosphatidylcholine and sphingomyelin of M. orale were derived from the medium. The 14C-labeling experiment demonstrates that no fatty acid synthesis takes place nor exogenous fatty acid can be incorporated so efficiently as phosphatidylglycerol, suggesting that extremely high proportion of saturated fatty acyl residues in these phospholipids is the consequence of saturation directed to the acyl chains of the incorporated phospholipids.
Topics: Acetates; Animals; Arginine; Blood; Carbon Radioisotopes; Cholesterol; Culture Media; Fatty Acids; Horses; Membrane Lipids; Mycoplasma; Palmitic Acid; Palmitic Acids; Phosphates; Phospholipids; Phosphorus Radioisotopes
PubMed: 1594658
DOI: No ID Found -
The Journal of Infectious Diseases Oct 1968
Topics: Cell Division; Membranes, Artificial; Mycoplasma; Ultrasonics; Ultraviolet Rays
PubMed: 5698697
DOI: 10.1093/infdis/118.4.436 -
Scandinavian Journal of Infectious... 1998We examined 6 C. pneumonia isolates from The American Type Culture Collection (ATCC) and 2 Finnish isolates for Mycoplasma contamination. Three of the ATCC isolates and...
We examined 6 C. pneumonia isolates from The American Type Culture Collection (ATCC) and 2 Finnish isolates for Mycoplasma contamination. Three of the ATCC isolates and both of the Finnish isolates were Mycoplasma-contaminated. The contaminants were characterized by means of growth in BEa and BEg media, immunoblotting, polymerase chain reaction and pulsed field gel electrophoresis. Two of the 6 ATCC isolates [ATCC VR1355 (TWAR strain 2043) and ATCC VR1356 (TWAR strain 2023)] were infected with Mycoplasma hominis and 1 isolate [ATCC VR2282 (TWAR strain TW183)] was contaminated with both Mycoplasma hominis and Mycoplasma orale, whereas 3 of the ATCC isolates [ATCC VR1310, ATCC VR1360 (TWAR strain CM-1) and ATCC 53592 (TWAR strain AR39)] were not contaminated. The Finnish C. pneumoniae isolates Kajaani 6 and Parola were found to be contaminated with M. hominis and M. orale, respectively. The contamination of C. pneumoniae stock cultures, frequently used in the microimmunofluorescence test, with human pathogens, could pose a serious problem in C. pneumoniae serology.
Topics: Bacteriological Techniques; Base Sequence; Chlamydophila pneumoniae; Culture Media; Denmark; Equipment Contamination; Humans; Molecular Sequence Data; Mycoplasma; Polymerase Chain Reaction
PubMed: 9730308
DOI: 10.1080/003655498750003609 -
The American Journal of Medicine Apr 1986The incidence and morbidity of Mycoplasma infections were examined in a group of 23 patients with hypogammaglobulinemia. Among this group of patients, 18 had one or more...
The incidence and morbidity of Mycoplasma infections were examined in a group of 23 patients with hypogammaglobulinemia. Among this group of patients, 18 had one or more episodes of acute respiratory illness during which Ureaplasma urealyticum, Mycoplasma orale, or Mycoplasma pneumoniae were isolated from sputum. Resolution only followed institution of specific antibiotic therapy and elimination of the Mycoplasma. In addition to respiratory illness, U. urealyticum was isolated from the urine of two patients with urinary tract infection and from an area of cellulitis in another patient. M. pneumoniae was isolated from the joint of a patient with arthritis. In six patients with chronic lung disease, Mycoplasma was frequently isolated and clinical improvement, albeit transient, coincided with negative Mycoplasma culture results. These findings emphasize the unique susceptibility to Mycoplasma infection in patients with hypogammaglobulinemia.
Topics: Adolescent; Adult; Agammaglobulinemia; Disease Susceptibility; Female; Humans; Male; Mycoplasma Infections; Ureaplasma
PubMed: 3963038
DOI: 10.1016/0002-9343(86)90812-0 -
Research in Microbiology Apr 2013The presence of foreign contamination, especially of mycoplasmas, is a major hindrance in long term in vitro cultivation of Plasmodium falciparum and may be a source of...
The presence of foreign contamination, especially of mycoplasmas, is a major hindrance in long term in vitro cultivation of Plasmodium falciparum and may be a source of false-positive results. Efforts have been made to control mycoplasma contamination by trypsinization of P. falciparum culture. Samples of accidentally contaminated cultures were used for this study. The presence of Mycoplasma orale in contaminated culture was ascertained by a species-specific PCR-based mycoplasma detection kit (Takara; Cat. No.6601). Trypsinization was carried out using trypsin-EDTA and the growth profile of P. falciparum was monitored for more than three weeks post-trypsinization. The studies were carried out with four different P. falciparum strains, various serum supplements and human erythrocytes belonging to different blood groups. It was interesting to observe that, irrespective of the different strains of P. falciparum and the variety of serum supplements and erythrocytes, mycoplasma contamination can successfully be removed from P. falciparum culture by trypsinization. No antibiotic except gentamicin, which is routinely used, was added to the medium. Results of this study indicate that the frequent appearance of mycoplasma in continuous long-term cultures of P. falciparum can be managed by trypsinization.
Topics: Anti-Bacterial Agents; Cell Culture Techniques; Culture Media; Erythrocytes; Gentamicins; Humans; Mycoplasma orale; Plasmodium falciparum; Trypsin
PubMed: 23277231
DOI: 10.1016/j.resmic.2012.12.010 -
Current Microbiology Jan 2021Mycoplasma is the smallest self-replicating bacteria, figuring as common contaminant of eukaryotic cell cultures. Production inputs and operator's manipulation seem to...
Mycoplasma is the smallest self-replicating bacteria, figuring as common contaminant of eukaryotic cell cultures. Production inputs and operator's manipulation seem to be the main sources of such contamination. Many analytical approaches have been applied for mycoplasma detection in cell cultures and also in biological products. However, unless they were validated, only indicator cell culture and bacteriological culture are considered as compendial methods for quality control of biological products. Nano-flow cytometry has been pointed out as an alternative technique for addressing prokaryotic and eukaryotic cell viability being a substantial tool for reference material production. In this study, a viability-flow-cytometry assay was standardized for M. gallisepticum and then applied to other cell-culture-contaminant mycoplasmas. For this, M. galliseticum's growth rate was observed and different treatments were evaluated to establish low viability cultures (cell death-induced control). Distinct viability markers and their ideal concentrations (titration) were appraised. Ethanol treatment showed to be the best death-inducing control. CFDA and TOPRO markers revealed to be the best choice for detecting live and dead mycoplasma frequencies, respectively. The standardized methodology was applied to Mycoplasma arginini, M. hyorhinis, M. orale, Spiroplasma citri and Acholeplasma laidlawii. Significant statistical difference was observed in the percentage of viable cells in comparison to ethanol treatment for A. laidlawii in CFDA and in both markers for M. gallisepticum, M. hyorhinis and S. citri. In summary, we standardized a flow cytometry assay for assessing M. gallisepticum - and potentially other species - viability and ultimately applied for reference material production improving the quality control of biological products.
Topics: Cell Culture Techniques; Flow Cytometry; Mycoplasma; Mycoplasma gallisepticum; Tenericutes
PubMed: 33159562
DOI: 10.1007/s00284-020-02255-1