Development of a Screening Test for Detection of Streptococcus suis Serotype 2

Abstract

Streptococcus suis (S.suis) is typically a swine pathogen  that can cause death in human. Routine  diagnosis of this swine pathogen  in infected  patient is complicated and  time consuming. The  purpose  of  this  study  was  to develop  an  easy,  convenient  and  quick  screening test  for detecting  S,  suis.  Firstly,  Rabbits  were  immunized  with capsular  polysaccharide (cps) antigen of   S. suis   serotype 2. Serum was  collected  for   detecting anti-cps  by  indirect  ELISA. Nonspecific   antibodies were   removed  by  adsorption method.  Then,   the  adsorbed anti-cps antibodies were  used  to develop  a  screening test  using  latex  agglutination test.  Finally,  the screening test was evaluated  using cps of  S. suis and cps or extracted  cell membrane of other organisms. The results showed that serum contained  nonspecific and specific anti-cps antibodies. The  non-specific antibodies could   not  be  adsorbed  completely, The  screening  test  made from  the adsorbed anti-cps antibodies was able  to detect  the lower  limit  of cps of  S. suis  at

125  11g/mL and cross-react to cps of S. pyogenes. In conclusion,  this study  is able  to develop a screening  test for detecting  S.suis by choosing an alpha hemolysis and gram-positive bacteria for  performing with this kit.