The lipopolysaccharide (R type) as a common antigen of Neisseria gonorrhoeae. II. Use of hen antiserum to gonococcal lipopolysaccharide in a rapid slide test for the identification of N. gonorrhoeae from primary isolates and secondary cultures.

An antiserum has been prepared in hens to R-type gonococcal lipopolysaccharide (LPS) and used in a simple slide-agglutination test for the identification of Neisseria gonorrhoeae. Anti-LPS serum agglutinated gonococcal cells representative of the four colony types of N. gonorrhoeae. Absorption of the antiserum with LPS removed the agglutinating activity. Secondary cultures (1120) were tested without observation of the colony type and all were agglutinated. No agglutination occurred with strains of Neisseria meningitidis, Neisseria lactamica, non-pathogenic Neisseria. Pseudomonas aeruginosa, Branhamella catarrhalis, or with species of lactobacilli and Acinetobacter. Cross-reactivity of the antiserum occurred with some streptococci. The anti-LPS serum was used to identify N. gonorrhoeae in primary isolates from the cervix, urethra, and pharynx. Of 251 gonococcal isolates tested, 249 were agglutinated by the antiserum, while all of the corresponding second cultures were agglutinated. The antiserum did not agglutinate N. meningitidis found in primary isolates from pharyngeal specimens. Anti-LPS hen serum should be useful for the rapid identification of N. gonorrhoeae in primary isolates or secondary cultures.