Immune Responses to Bacillus Anthracis Protective Antigen in Patients With Bioterrorism-Related Cutaneous or Inhalation Anthrax

J Infect Dis. 2004 Oct 1;190(7):1228-36. doi: 10.1086/423937. Epub 2004 Aug 30.


Anti-protective antigen (PA) immunoglobulin (Ig) G, toxin neutralization, and PA-specific IgG memory B cell responses were studied in patients with bioterrorism-related cutaneous or inhalation anthrax and in a patient with laboratory-acquired cutaneous anthrax. Responses were determined for >1 year after the onset of symptoms. Eleven days after the onset of symptoms (15 days after likely exposure), anti-PA IgG was detected in 16 of 17 patients with confirmed or suspected clinical anthrax who were tested. Anti-PA IgG remained detectable 8-16 months after the onset of symptoms in all 6 survivors of inhalation anthrax and in 7 of 11 survivors of cutaneous anthrax who were tested. Anti-PA IgG levels and serum toxin neutralizing activity were strongly associated (R2=0.83). PA-specific IgG memory B cells were detectable in all 6 survivors of inhalation anthrax but in only 2 of 7 patients with cutaneous anthrax who were tested. Anti-PA IgG is an important diagnostic marker of anthrax, a predictor of serum anti-toxin activity, and a marker of immunological memory against anthrax.

Publication types

  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Anthrax / immunology*
  • Antibodies, Bacterial / blood*
  • Antigens, Bacterial / immunology*
  • B-Lymphocytes / immunology
  • Bacterial Toxins / immunology*
  • Bioterrorism*
  • Enzyme-Linked Immunosorbent Assay
  • Humans
  • Immunoglobulin G / blood
  • Immunologic Memory
  • Lung Diseases / immunology
  • Neutralization Tests
  • Skin Diseases / immunology


  • Antibodies, Bacterial
  • Antigens, Bacterial
  • Bacterial Toxins
  • Immunoglobulin G
  • anthrax toxin