Syphilis Ab Version ULTRA
Enzyme ImmunoAssay (ELISA) for the qualitative determination of antibodies (IgG, IgM and IgA) to Treponema Pallidum. The kit may be used for the screening of blood units and the follow-up of Tp-infected patients.
Syphilis is a sexually transmitted disease caused by Treponema pallidum or Tp, bacterium belonging to the family of Spirochaetaceae. Tp is gram negative and is considered strictly anaerobe, exhibiting a characteristic mobility due to periplasmic flagella. A cell wall and a cytoplasmic membrane enclose the cytoplasmatic content.
Syphilis is a complex, acute, chronic infectious disease with diverse clinical manifestations, depending upon the stage of infection and the individual response. The period of incubation ranges from 10 days to 3 months and antibodies are usually detected after 2-4 weeks from the primary lesion.
Many assays have been developed for the immunological detection of the T.pallidum infection in the past (VDRL, TPHA, RPR) still currently in use at the diagnostic laboratory.
Recently, ELISA techniques have been applied to syphilis antibody screening in blood banks and Infectious Disease Departments, allowing the clinicians to use automatic analysis instruments and optical reading records.
Microplates are coated with purified Treponema pallidum synthetic antigens.
The solid phase is first treated with the sample and anti Tp Ab are captured, if present, by the antigens coated on the microplate.
After washing out all the other components of the sample, in the second incubation bound anti Tp total antibodies, are detected by the addition of Tp synthetic antigens, labelled with peroxidase (HRP).
The enzyme captured on the solid phase, acting on the substrate/chromogen mixture, generates an optical signal that is proportional to the amount of anti Tp antibodies present in the sample. After blocking the enzymatic reaction, its optical density is measured by an ELISA reader.
The version ULTRA is particularly suitable for automated screenings.
- Zhonghua yi xue za zhi 87:24 2007 Jun 26 pg 1721-2 Wang LN, Zheng HY, Li J, Wang XF, Liu XR Sensitivity and specificity of ELISA based on recombinant Treponema pallidum antigen and rapid plasma reagin test in diagnosis of syphilis: a comparative study.
- Dermatol Clin. 1998 Oct;16(4):691-8.Syphilis. Serology. Young H.
- Evaluation of an enzyme immunoassay technique for detection of antibodies against Treponema pallidum. Castro R, Prieto ES, Santo I, Azevedo J, Exposto Fda L. J Clin Microbiol. 2003 Jan; 41(1):250-3.
- Are Treponema pallidum Specific Rapid and Point-of-Care Tests for Syphilis Accurate Enough for Screening in Resource Limited Settings? Evidence from a Meta-Analysis. Jafari Y, Peeling RW, Shivkumar S, Claessens C, Joseph L, Pai NP. PLoS One. 2013; 8(2):e54695. Epub 2013 Feb 26.