title: Detection of IgG antibodies in sera from patients with Cryptosporidium parvum and Cryptosporidium hominis.
abstract: OBJECTIVE
  Detection of anti-Cryptosporidium immunoglobulin G (IgG) antibodies in human sera has been used to demonstrate population exposure to this gastro-intestinal protozoan parasite. We characterised the dynamics of IgG antibody responses to two Cryptosporidium parvum (IOWA isolate) sporozoite antigens (15/17 kDa and 27 kDa) using longitudinal sera taken from laboratory-confirmed cryptosporidiosis cases in England and Wales. The effect of the infecting Cryptosporidium species was also investigated.
  
  
  METHODS
  A mini-gel Western blot was used to test sera from ten Cryptosporidium stool-positive diarrhoea patients, taken soon after diagnosis and at 3 month intervals.
  
  
  RESULTS
  Overall responses to the 15/17 kDa antigen complex were stronger and over a greater range than those to the 27 kDa antigen, but declined between 181 and 240 days and were barely detectable thereafter. Responses to the 27 kDa antigen were much weaker but remained detectable for a greater length of time. No differences were detected in either antibody response to infection with C. hominis or C. parvum.
  
  
  CONCLUSIONS
  The assay appears to be applicable for the study of recent exposure to C. parvum or C. hominis in the United Kingdom population, with strong responses to the 15/17 kDa antigen occurring within 6 months of infection.
authors: Cryptosporidium Reference Unit, Public Health Wales Microbiology, Singleton Hospital, Swansea SA2 8QA, UK. rachel.chalmers@wales.nhs.uk
authors: Rachel M
authors: RM
authors: Chalmers
authors: Kristin
authors: K
authors: Elwin
authors: John
authors: J
authors: Cheesbrough
authors: Stephen J
authors: SJ
authors: Hadfield
authors: Nicholas J
authors: NJ
authors: Beeching
mesh_terms: D000328:Adult; D000368:Aged; D000913:Antibodies, Protozoan / Q000097:blood*; D015153:Blotting, Western; D015331:Cohort Studies; D003457:Cryptosporidiosis / Q000175:diagnosis / Q000276:immunology / Q000469:parasitology*; D003458:Cryptosporidium / Q000145:classification / Q000276:immunology*; D016785:Cryptosporidium parvum / Q000145:classification / Q000276:immunology*; D005260:Female; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood*; D008297:Male; D008875:Middle Aged; D010274:Parasitology / Q000379:methods; D012698:Serologic Tests
chemical_list: D000913:Antibodies, Protozoan; D007074:Immunoglobulin G
keywords: Antibody response; Cryptosporidium; Cryptosporidium hominis; Cryptosporidium parvum; IgG; Mini-gel Western blot