Immunofluorescent staining of Treponema pallidum and Treponema pertenue in tissues fixed by formalin and embedded in paraffin wax.

Abstract

SUMMARY The main problems in identifying Treponema pallidum in tissues are optical definition, contrast, and specificity. In general, fluorochrome staining provides optical definition and contrast superior to that obtained by ordinary tinctorial staining, and in theory improved resolution. Specificity is lacking however, as with other stains. In contrast, immunofluorescence should combine the optical advantages of fluorochrome staining with the immunological advantages of specificity. Since the validity of such staining depends in part upon the integrity of the antigenic components of the micro-organisms, it is customary to avoid such drastic procedures as are involved in routine fixation and paraffin embedding. The manipulation, however, of unfixed cryostat material, in contrast with that of paraffin sections suffers from two disadvantages-namely, friability and infectivity. Published and unpublished work has shown antigenic stability in T. pallidum to a variety of procedures, both physical and chemical. Consideration of these facts led in this work to successful immunofluorescent staining after routine formalin fixation and paraffin embedding of tissues infected with T. pallidum or Treponema pertenue. Optical definition and contrast, were superior to that obtained with silver methods, but it was not possible to differentiate between these two organisms. Nevertheless immunofluorescence applied as described to paraffin sections should supply a convenient, safe, and sensitive means of reappraising the histopathology of treponemal disease in patients, necropsy material, and experimental animals.

Alopecia syphilitica with detection of Treponema pallidum in the hair follicle

“…Al‐Samarrai and Henderson reported an immunofluorescence technique that was useful in paraffin‐embedded tissue sections. However, as described in other tissues, the reactivity diminished after storage 10 . Molecular detection by polymerase chain reaction of T. pallidum has also been tried.…”

“…However, as described in other tissues, the reactivity diminished after storage. 10 Molecular detection by polymerase chain reaction of T. pallidum has also been tried. This technique was the first known method for the direct detection of T. pallidum in scalp lesions, but two major risks have been described: the first is the presence of false-positive cases and the second is the possibility of true-positive results that have no specific pathogenic relevance.…”

Secondary syphilis: a histologic and immunohistochemical evaluation

“…An early demonstration of spirochetes by immunofluorescence method was detailed by Yobs et al 12 ; however, fresh tissue was needed and fluorescent artifact necessitated comparison with silver stain. Al‐Samarrai and Henderson 13 were the first to demonstrate a successful immunofluorescence method for detecting treponemes in paraffin‐embedded tissue in experimental animals, yet reactivity diminished with storage. Beckett and Bigbee 11 were the first to demonstrate that immunoperoxidase method was superior to the conventional techniques.…”

Immunoperoxidase technique for detecting spirochetes in tissue sections: comparison with other methods

“…Al‐Samarrai and Henderson 15 were the first to demonstrate a successful immunofluorescence method for detecting treponemes in paraffin‐embedded tissue in experimental animals. They documented that it was vastly superior to silver stains and could be used in detecting spirochetes in formalin‐fixed, paraffin‐embedded tissue.…”