Scientific Publications by FDA Staff

J Clin Microbiol 2004 Jul;42(7):3225-31

Antigenic evidence of prevalence and diversity of Mycobacterium tuberculosis arabinomannan.

Glatman-Freedman A, Casadevall A, Dai Z, Jacobs WR Jr, Li A, Morris SL, Navoa JA, Piperdi S, Robbins JB, Schneerson R, Schwebach JR, Shapiro M

Glatman-Freedman A, Yeshiva Univ Albert Einstein Coll Med, Childrens Hosp, Dept Pediat, Golding Bldg,Room 702,1300 Morris Pk Ave, Bronx, NY 10461 USA Yeshiva Univ Albert Einstein Coll Med, Childrens Hosp, Dept Pediat, Bronx, NY 10461 USA Yeshiva Univ Albert Einstein Coll Med, Dept Med, Bronx, NY 10461 USA Yeshiva Univ Albert Einstein Coll Med, Dept Microbiol & Immunol, Bronx, NY 10461 USA Yeshiva Univ Albert Einstein Coll Med, Howard Hughes Med Inst, Bronx, NY 10461 USA NICHHD, NIH, Bethesda, MD 20892 USA US FDA, Ctr Biol Evaluat & Res, Bethesda, MD 20014 USA

Arabinomannan (AM) is a polysaccharide of the mycobacterial capsule. The capsular polysaccharides of various microorganisms are diverse, and this diversity is important for classification of organisms into serotypes and vaccine development. In the present study we examined the prevalence and diversity of AM among Mycobacterium tuberculosis strains using four AM-binding monoclonal antibodies (MAbs). One of these MAbs, MAb 9d8, is known to bind to AM specifically. By whole-cell enzyme-linked immunosorbent assay (ELISA), the AM recognized by MAb 9d8 was detected on the surfaces of 9 of 11 strains, while 2 strains showed no reactivity with MAb 9d8. However, the AM recognized by MAb 9d8 was found in the culture supernatants of all 11 M. tuberculosis strains tested, as demonstrated by capture ELISA. Other AM-binding MAbs reacted both with the surfaces and with the culture supernatants of all 11 strains. Mice immunized with an experimental AM-recombinant Pseudomonas aeruginosa exoprotein A (rEPA) conjugate vaccine had an increased antibody response to AM and a moderate reduction in the numbers of CFU in their organs 7 days after challenge. Our results indicate that AM was detected in all M. tuberculosis strains tested, with differences in epitope distributions of certain strains. In addition, our results suggest that an experimental AM-rEPA vaccine has a moderate effect on the numbers of CFU in organs early after infection.