[1] SYNTEX RES CORP, DEPT MOLEC IMMUNOL, 3401 HILLVIEW AVE, PALO ALTO, CA 94304 USA
[2] ROCHE INST MOLEC BIOL, NUTLEY, NJ 07110 USA
[3] WASHINGTON UNIV, JEWISH HOSP ST LOUIS, SCH MED, DEPT PATHOL & LAB MED, ST LOUIS, MO 63110 USA
[4] WASHINGTON UNIV, SCH MED, DEPT MICROBIOL & IMMUNOL, ST LOUIS, MO 63110 USA
[5] ST LOUIS UNIV, SCH MED, DEPT MICROBIOL, ST LOUIS, MO 63110 USA