scholarly journals Cytotoxicity of Mycoplasma mycoides subsp. mycoides Small Colony Type to Bovine Epithelial Cells

2007 ◽  
Vol 76 (1) ◽  
pp. 263-269 ◽  
Author(s):  
Daniela F. Bischof ◽  
Carole Janis ◽  
Edy M. Vilei ◽  
Giuseppe Bertoni ◽  
Joachim Frey
Keyword(s):  
Close Contact ◽  
Clinical Signs ◽  
Host Cells ◽  
Uptake System ◽  
Contagious Bovine Pleuropneumonia ◽  
Colony Type ◽  
Mycoplasma Mycoides ◽  
Small Colony ◽  
High Cytotoxicity

ABSTRACT The cytotoxicities of various strains of Mycoplasma mycoides subsp. mycoides small colony type (SC), the agent of contagious bovine pleuropneumonia (CBPP), were measured in vitro using embryonic calf nasal epithelial (ECaNEp) cells. Strains isolated from acute cases of CBPP induced high cytotoxicity in the presence of glycerol, concomitant with the release of large amounts of toxic H2O2 that were found to be translocated into the cytoplasms of the host cells by close contact of the Mycoplasma strains with the host cells. Currently used vaccine strains also showed high cytotoxicity and high H2O2 release, indicating that they are attenuated in another virulence attribute. Strains isolated from recent European outbreaks of CBPP with mild clinical signs, which are characterized by a defect in the glycerol uptake system, released small amounts of H2O2 and showed low cytotoxicity to ECaNEp cells. M. mycoides subsp. mycoides SC strain PG1 released large amounts of H2O2 but was only slightly cytotoxic. PG1 was found to have a reduced capacity to bind to ECaNEp cells and was unable to translocate H2O2 into the bovine cells, in contrast to virulent strains that release large amounts of H2O2. Thus, an efficient translocation of H2O2 into host cells is a prerequisite for the cytotoxic effect and requires an intact adhesion mechanism to ensure a close contact between mycoplasmas and host cells.

scholarly journals Characterization of Strains of Mycoplasma mycoidessubsp. mycoides Small Colony Type Isolated from Recent Outbreaks of Contagious Bovine Pleuropneumonia in Botswana and Tanzania: Evidence for a New Biotype

2000 ◽  
Vol 38 (4) ◽  
pp. 1419-1425 ◽  
Author(s):  
John B. March ◽  
Jason Clark ◽  
Malcolm Brodlie
Keyword(s):  
Capsular Polysaccharide ◽  
Evolutionary Relationship ◽  
High Sensitivity ◽  
Contagious Bovine Pleuropneumonia ◽  
Poor Growth ◽  
Colony Type ◽  
Protective Antigens ◽  
Mycoplasma Mycoides ◽  
Small Colony

Four strains of Mycoplasma mycoides subsp.mycoides small colony type (MmmSC) isolated from recent outbreaks of contagious bovine pleuropneumonia (CBPP) in Africa have been investigated. One Botswanan strain, M375, displayed numerous and significant phenotypic differences from both contemporary field isolates and older field and vaccine strains (African, Australian, and European strains dating back to 1936). Differences include altered morphology, reduced capsular polysaccharide production, high sensitivity to MmmSC rabbit hyperimmune antisera in vitro, and unique polymorphisms following immunoblotting. While insertion sequence analysis using IS1634 clearly indicates a close evolutionary relationship to west African strains, hybridization with IS1296 shows the absence of a band present in all other strains of MmmSC examined. The data suggest that a deletion has occurred in strain M375, which may explain its altered phenotype, including poor growth in vitro and a relative inability to cause septicemia in mice. These characteristics are also exhibited byMycoplasma capricolum subsp. capripneumoniae(causal agent of contagious caprine pleuropneumonia [CCPP]), against which M375 antiserum exhibited some activity in vitro (unique among the various MmmSC antisera tested). These findings may have evolutionary implications, since CCPP is believed to be lung specific and without a septicemic phase (unlike CBPP). Since M375 was isolated from a clinical case of CBPP, this novel biotype may be fairly widespread but not normally isolated due to difficulty of culture and/or a potentially altered disease syndrome. Bovine convalescent antisera (obtained from contemporary naturally infected cattle in Botswana) were active against strain M375 in an in vitro growth inhibition test but not against any other strains of MmmSC tested. There exists the possibility therefore, that strain M375 may possess a set of protective antigens different from those of other strains of MmmSC (including vaccine strains). These findings have implications for the control of the current CBPP epidemic in Africa.

scholarly journals Assessing the In Vitro Effectiveness of Antimicrobials against Mycoplasma mycoides subsp. mycoides Small-Colony Type To Reduce Contagious Bovine Pleuropneumonia Infection

2005 ◽  
Vol 49 (12) ◽  
pp. 5162-5165 ◽  
Author(s):  
R. D. Ayling ◽  
S. Bisgaard-Frantzen ◽  
J. B. March ◽  
K. Godinho ◽  
R. A. J. Nicholas
Keyword(s):  
Antimicrobial Resistance ◽  
Contagious Bovine Pleuropneumonia ◽  
Colony Type ◽  
Minimum Inhibitory Concentrations ◽  
Mycoplasma Mycoides ◽  
Small Colony

ABSTRACT In vitro minimum inhibitory concentrations were determined for 21 antimicrobials against 41 isolates of Mycoplasma mycoides subsp. mycoides small-colony type, the cause of contagious bovine pleuropneumonia. Of the antimicrobials used most widely in Africa, oxytetracycline and tilmicosin were effective, while the isolates were resistant to tylosin. These results provide a baseline for monitoring antimicrobial resistance.

scholarly journals Clinical, humoral and IFN g responses of cattle to infection with Mycoplasma mycoides var. mycoides small colony and attempts to condition the pathogenesis of the infection

2007 ◽  
Vol 74 (3) ◽  
Author(s):  
M. Scacchia ◽  
F. Sacchini ◽  
G. Filipponi ◽  
M. Luciani ◽  
R. Lelli ◽  
...  
Keyword(s):  
Immune Response ◽  
Clinical Signs ◽  
Cell System ◽  
Contagious Bovine Pleuropneumonia ◽  
Entire Observation Period ◽  
Mycoplasma Mycoides ◽  
Small Colony ◽  
Immunopathological Process ◽  
Observation Period

Contagious bovine pleuropneumonia (CBPP), caused by Mycoplasma mycoides var. mycoides small colony (MmmSC), is one of the most important diseases of cattle in Africa. The role of innate or acquired cell mediated and humoral immunity in conferring protection against MmmSC infection has not yet been elucidated. On the other hand, the pathological lesions caused by the aetiological agent have been considered indicative of an immunopathological process. In this study ten naïve cattle were exposed to in-contact infection with animals infected by intubation with a strain of MmmSC. Clinical signs, antibody response, IFNg release and pathological changes at necropsy were analysed and compared with the events following in-contact infection of an equal number of animals kept under daily treatment with cyclosporine for the entire observation period of 84 days. Cyclosporine is a suppressor of the immune response related to the T-cell system. Under the conditions of the experiment, cyclosporine appeared to condition the pathogenesis of CBPP by delaying the events that follow infection, bringing further support to the possibility that the immune response may have an impact on the disease outcome.

scholarly journals Monoclonal Antibody Differentiation ofMycoplasma mycoides subsp. mycoides Small-Colony Strains Causing Contagious Bovine Pleuropneumonia from Less Important Large-Colony Strains

2000 ◽  
Vol 7 (3) ◽  
pp. 519-521 ◽  
Author(s):  
Fred R. Rurangirwa ◽  
Patrick S. Shompole ◽  
Anderson N. Wambugu ◽  
Travis C. McGuire
Keyword(s):  
Monoclonal Antibody ◽  
Growth Inhibition ◽  
In Vitro Growth ◽  
Contagious Bovine Pleuropneumonia ◽  
Large Colony ◽  
Mycoplasma Mycoides ◽  
Small Colony ◽  
Polyclonal Antisera

ABSTRACT Monoclonal antibody (MAb) PK-2 inhibited the in vitro growth of nine Mycoplasma mycoides subsp. mycoidessmall-colony strains. In contrast to the results with polyclonal antisera, growth inhibition by MAb PK-2 was specific for M. mycoides subsp. mycoides small-colony strains and constituted a reliable means of distinguishing them from other mycoplasmas.

scholarly journals Modelling Bovine Granuloma Formation In Vitro upon Infection with Mycobacterium Avium Subspecies Paratuberculosis

2019 ◽  
Vol 6 (4) ◽  
pp. 80 ◽  
Author(s):  
J. Hunter Rice ◽  
Margaret M. McDaniel ◽  
Alyson Holland ◽  
Shigetoshi Eda
Keyword(s):  
Mycobacterium Avium ◽  
Mycobacterium Avium Subspecies Paratuberculosis ◽  
Clinical Signs ◽  
Host Cells ◽  
Economic Losses ◽  
Multiple Parameters ◽  
Cell Mediated Immune Response ◽  
A Cell ◽  
Vitro Model

Mycobacterium avium subspecies paratuberculosis (Map) causes chronic granulomatous disease in cattle and ruminant livestock, causing substantial economic losses. Current vaccines delay clinical signs but cannot train the immune system to fully eradicate latent Map. During latency, Map uses host defenses, cage-like macrophage clusters called granuloma, as incubators for months or years. We used an in vitro model to investigate the early coordination of macrophages into granuloma upon Map infection over ten days. We found that at multiplicities of infection (MOI; Map:macrophages) of 1:2 and below, the macrophages readily form clusters and evolve pro-inflammatory cytokines in keeping with a cell-mediated immune response. At higher MOIs, viability of host macrophages is negatively impacted. At 1:4 MOI, we quantified viable Map in our model and confirmed that intracellular Map reproduced over the first five days of infection. Host cells expressed Type 1-specific cytokines, and Map-infected macrophages displayed reduced motility compared to Map-exposed, uninfected macrophages, suggesting an important role for uninfected macrophages in the early aggregative response. Reported is the first in vitro JD granuloma model capturing Map and macrophage viability, size distribution of resulting clusters, motility of monocyte-derived macrophages, and cytokine response during clustering, allowing quantitative analysis of multiple parameters of the Map-specific granulomatous response.

scholarly journals Variable Surface Protein Vmm of Mycoplasma mycoides subsp. mycoides Small Colony Type

2002 ◽  
Vol 184 (13) ◽  
pp. 3712-3722 ◽  
Author(s):  
Anja Persson ◽  
Karin Jacobsson ◽  
Lars Frykberg ◽  
Karl-Erik Johansson ◽  
François Poumarat
Keyword(s):  
Phase Variation ◽  
Surface Protein ◽  
Transcriptional Level ◽  
Colony Type ◽  
Mycoplasma Capricolum ◽  
Binding Epitope ◽  
Variable Surface ◽  
Mycoplasma Mycoides ◽  
Small Colony ◽  
Reversible Phase

ABSTRACT A variable surface protein, Vmm, of the bovine pathogen Mycoplasma mycoides subsp. mycoides small colony type (M. mycoides SC) has been identified and characterized. Vmm was specific for the SC biotype and was expressed by 68 of 69 analyzed M. mycoides SC strains. The protein was found to undergo reversible phase variation at a frequency of 9 × 10−4 to 5 × 10−5 per cell per generation. The vmm gene was present in all of the 69 tested M. mycoides SC strains and encodes a lipoprotein precursor of 59 amino acids (aa), where the mature protein was predicted to be 36 aa and was anchored to the membrane by only the lipid moiety, as no transmembrane region could be identified. DNA sequencing of the vmm gene region from ON and OFF clones showed that the expression of Vmm was regulated at the transcriptional level by dinucleotide insertions or deletions in a repetitive region of the promoter spacer. Vmm-like genes were also found in four closely related mycoplasmas, Mycoplasma capricolum subsp. capricolum, M. capricolum subsp . capripneumoniae, Mycoplasma sp. bovine serogroup 7, and Mycoplasma putrefaciens. However, Vmm could not be detected in whole-cell lysates of these species, suggesting that the proteins encoded by the vmm-like genes lack the binding epitope for the monoclonal antibody used in this study or, alternatively, that the Vmm-like proteins were not expressed.

Characterization of the gene for an immunodominant 72 kDa lipoprotein of Mycoplasma mycoides subsp. mycoides small colony type

Microbiology ◽  
1996 ◽  
Vol 142 (12) ◽  
pp. 3515-3524 ◽  
Author(s):  
X. Cheng ◽  
J. Nicolet ◽  
R. Miserez ◽  
P. Kuhnert ◽  
M. Krampe ◽  
...  
Keyword(s):  
Colony Type ◽  
Mycoplasma Mycoides ◽  
Small Colony
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