Identification of Neisseria gonorrhoeae by Means of Fluorescent Antibodies

Diagnosis of Gonorrhea by a Fluorescent Antibody Technique

“…The excess FITC was removed by dialysis during 72 h. The optimal dilution of the conjugate, th at is the highest dilution (usually 3-4 times) which gave rise to maximum fluorescence, was established by applying the FA technique described below to specimens of 24-h gonococcal cultures. Absorption of conjugates with genus-specific antigens was con sidered unnecessary in view of the findings of Deacon et al (1959) in experiments with other Neisseriae. After diluting the conjugate with phosphate buffer pH 7.2 (PB), it was divided into 0.3-ml samples and frozen at -29° C in rubber-stoppered tubes.…”

“…Roughly following the technique of Deacon et al (1959), preliminary experiments with specimens of 24-h gonococcal cultures led to the technique de scribed below.…”

“…For the preparation of specific antisera in rabbits we used a technique described by Deacon et al (1959), making use of cultures of Neisseria gonorrhoeae killed with 0.3% formalin and mixed with Freund's adjuvant for the first (subcutaneous) injection. The sera obtained after exsanguina tion of the rabbits were kept at --20°C in samples of 10 ml.…”

Method for Preparing Neisseria gonorrhoeae Fluorescent Antibody Conjugate

“…'HE direct-staining fluorescent antibody (FA) technique has proved useful as a laboratory aid in the identification of Neisseria gonorrhoeae, or gonococcus (1)(2)(3)(4)(5)(6)(7)(8)(9)(10)(11)(12)). An effective method for producing satisfactory fluorescein conjugated antiserums to this gonococcus (GC) has been found.…”

II. The Diagnostic Application of Fluorescent Antibodies

“…The antigen is present only in freshly isolated cultures or in infectious exudate. Labelled antiserum containing antibodies against it brightly stained gono cocci in leukocytes smeared from cases of acute urethritis (Dea con, Peacock, Freeman and Harris, 1959).…”