Use of Trypanosoma Cruzi Purified Glycoprotein (GP57/51) or Trypomastigote-Shed Antigens to Assess Cure for Human Chagas' Disease

Diagnosis of Chagas disease: what has been achieved? What remains to be done with regard to diagnosis and follow up studies?

“…Some have argued that mice infected with T. cruzi but parasitologically cured after specific chemotherapy continue to exhibit positive IIF tests 3-6 months after treatment as a result of parasite antigens being trapped by certain cells in the spleen (Andrade et al 1991). Other studies have shown that a high proportion of antibodies detected by CS, in treated Chagas patients, are directed against the carbohydrate residue Galα1->3 Gal, a determinant also recognised by antibodies from noninfected healthy individuals (Gazzinelli et al 1993). Due to their widespread distribution among microorganisms of the intestinal and pulmonary microflora, these determinants may continue to stimulate lymphocytes previously primed by T. cruzi Galα1->3 Gal epitopes, thereby accounting for false-positive results in CP.…”

“…A number of serological techniques have been evaluated as possible substitutes for the CoML test by using an ELISA with purified (Gazzinelli et al 1993) and recombinant antigens (Krautz et al 1995, Silva et al 2002. Silva et al (2002) showed that when the serum from patients previously investigated using parasitological and serological tests and classified as CP (n = 10), DP (n = 6) and NCP (n = 6) was assayed using the EIE-Rec kit, all the serum samples from NCPs tested positive and all the samples from CP tested negative.…”

Tc45, a dimorphic Trypanosoma cruzi immunogen with variable chromosomal localization, is calreticulin.

“…[1][2][3][4][5][6] Although important contributions have been made to better define their potential role as immunogens or diagnostic tools, no functional characterization has been defined for the majority of the described parasite molecules. [1][2][3][4][5][6][7][8][9][10][11][12][13] The immunological functions of calreticulin in mammals have been delineated to some extent, in particular as a chaperone molecule in the process of antigen presentation to CD8ϩ T cells. Thus, when ␤ 2 -microglobulin binds to the major histocompatibility complex (MHC) class I ␣ chain, the partially folded ␣␤ 2 -microglobulin heterodimer dissociates from calnexin and binds calreticulin.…”

The utility of anti-trypomastigote lytic antibodies for determining cure of Trypanosoma cruzi infections in treated patients: an overview and perspectives

“…A high proportion of antibodies detected by CS tests are directed against carbohydrate residues. Indeed, sera negative in CoML tests also became negative in the CS test following immunoadsorption with melibiose (Gazzinelli et al 1993).…”