title: Development of a specific immunomagnetic capture-PCR for rapid detection of viable Mycoplasma agalactiae in sheep milk samples.
abstract: OBJECTIVE
  To develop an immunomagnetic capture (IMC) to detect viable Mycoplasma agalactiae in routine ovine milk samples.
  
  
  RESULTS
  Polyclonal antibodies against two M. agalactiae membrane surface proteins (P80 and P55) were covalently conjugated to magnetic beads (MBs) to form MB-Ab80 and MB-Ab55. Mycoplasma agalactiae cells were captured by a specific antigen-antibody reaction and magnetic separation. Immunomagnetic capture (IMC) was used to isolate and concentrate M. agalactiae in serial decimal dilutions and in artificially contaminated milk to facilitate subsequent detection by PCR. A 375-bp fragment of M. agalactiae was amplified using a pair of M. agalactiae-specific primers in PCR. The limit of detection of IMC-PCR method ranged from 10 to 10(2)  CCU ml(-1) when mycoplasmas were resuspended in PBS and from 10(2) to 10(3)  CCU ml(-1) when mycoplasmas were resuspended in uncontaminated ovine milk. This study also describes the application of IMC-PCR method to test for M. agalactiae in 516 milk samples collected from sheep with suspected contagious agalactia. Its performance was evaluated relative to culture.
  
  
  CONCLUSIONS
  This report has demonstrated for the first time, the effective use of rapid and reliable IMC combined with PCR assay for the detection of viable M. agalactiae.
  
  
  CONCLUSIONS
  The method IMC-PCR provides an alternative to conventional microbiological detection, method and it could be applied to quick detection of M. agalactiae in routine sheep milk samples.
authors.affiliation: Istituto ZooprofilatticoSperimentale della Sardegna "G. Pegreffi", Sassari, Italy.
authors.forename: G
authors.initials: G
authors.lastname: Sanna
authors.forename: V
authors.initials: V
authors.lastname: Lecca
authors.forename: A
authors.initials: A
authors.lastname: Foddai
authors.forename: S
authors.initials: S
authors.lastname: Tola
mesh_terms: D000818:Animals; D000907:Antibodies, Bacterial / Q000097:blood; D001426:Bacterial Proteins / Q000276:immunology; D018189:Immunomagnetic Separation / Q000379:methods*; D008565:Membrane Proteins / Q000276:immunology; D008892:Milk / Q000382:microbiology*; D009174:Mycoplasma / Q000302:isolation & purification; D045644:Mycoplasma agalactiae / Q000235:genetics / Q000276:immunology / Q000302:isolation & purification*; D016133:Polymerase Chain Reaction; D034561:Sheep, Domestic
chemical_list: D000907:Antibodies, Bacterial; D001426:Bacterial Proteins; D008565:Membrane Proteins
keywords: Mycoplasma agalactiae; PCR; antibodies; immunocapture; membrane surface proteins