title: T-cell receptor repertoire in pyoderma gangrenosum: evidence for clonal expansions and trafficking.
abstract: BACKGROUND
  The cause of pyoderma gangrenosum (PG) is unknown, but it is likely to be an immune-mediated disease because it is often associated with conditions such as inflammatory bowel disease and rheumatoid arthritis. T cells play an important role in these conditions and have been implicated in the pathogenesis of other skin diseases such as psoriasis.
  
  
  OBJECTIVE
  We examined the T-cell receptor repertoire in PG in order to test the hypothesis that if the T cells were responding to antigen, there would be expanded T-cell clones in the skin and the circulation of these patients.
  
  
  METHODS
  We studied five patients with PG and examined the T-cell receptor repertoire in cells taken from the peripheral blood and from biopsies of the ulcers, using complementarity determining region 3 spectratyping.
  
  
  RESULTS
  We were able to demonstrate expanded clones in the peripheral blood lymphocyte population of each patient. Clonal expansions within the skin were found in four of the five patients. Most significantly, expanded clones that were shared between the blood and the skin were revealed in four of the five patients.
  
  
  CONCLUSIONS
  These findings imply that T cells play an integral role in the development of PG and suggest that T cells are trafficking to the skin under the influence of an antigenic stimulus.
authors.affiliation: Clinical Science at South Bristol, Bristol Royal Infirmary, Marlborough Street, Bristol, BS2 8HW, UK.
authors.forename: T N
authors.initials: TN
authors.lastname: Brooklyn
authors.forename: A M
authors.initials: AM
authors.lastname: Williams
authors.forename: M G S
authors.initials: MG
authors.lastname: Dunnill
authors.forename: C S
authors.initials: CS
authors.lastname: Probert
mesh_terms: D000328:Adult; D002465:Cell Movement; D002999:Clone Cells; D017931:DNA Primers; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D017511:Pyoderma Gangrenosum / Q000235:genetics / Q000276:immunology*; D011948:Receptors, Antigen, T-Cell / Q000235:genetics / Q000276:immunology*
chemical_list: D017931:DNA Primers; D011948:Receptors, Antigen, T-Cell