Staining characteristics of six commercially available monoclonal immunofluorescence reagents for direct diagnosis of Chlamydia trachomatis infections.

Using purified elementary bodies of 14 Chlamydia trachomatis serovars in an in vitro assay, we compared the staining characteristics of six commercially available monoclonal antibody reagents used for direct immunofluorescent staining of patient smears. Considerable variation in the degree of brightness, consistency of staining, and specificity of the six reagents was found. Monoclonal antibodies against the major outer membrane proteins of C. trachomatis produced brighter fluorescence, more consistent elementary body morphology, and less nonspecific staining than did monoclonal antibodies directed against chlamydial lipopolysaccharide.