Direct fluorescent antibody confirmation for Bacillus anthracis targets which antigen?

Direct fluorescent antibody confirmation for Bacillus anthracis targets which antigen?

• A. Capsule antigen
• B. Capsular antigen/cell wall antigen
• C. Spore antigen
• D. Cell wall antigen

Answer: (B)

Direct fluorescent antibody confirmation relies on antibodies that bind to specific antigens on Bacillus anthracis to visualize the organism. For this pathogen, the most informative targets are the capsular antigen—the poly-D-glutamic acid capsule that surrounds virulent strains—and a distinctive cell wall antigen. Using antibodies against both the capsule and the cell wall increases the likelihood of detecting the organism in clinical specimens, since the capsule helps identify virulence and the cell wall antigen provides an additional reliable target. Spore antigens aren’t the typical focus of DFA in patient samples because spores are not usually the form present in routine clinical material.

Direct fluorescent antibody confirmation relies on antibodies that bind to specific antigens on Bacillus anthracis to visualize the organism. For this pathogen, the most informative targets are the capsular antigen—the poly-D-glutamic acid capsule that surrounds virulent strains—and a distinctive cell wall antigen. Using antibodies against both the capsule and the cell wall increases the likelihood of detecting the organism in clinical specimens, since the capsule helps identify virulence and the cell wall antigen provides an additional reliable target. Spore antigens aren’t the typical focus of DFA in patient samples because spores are not usually the form present in routine clinical material.