Recombinant Trypanosoma cruzi JL7 antigen variants and their use for detecting Chagas disease

Patent metadata

Field	Value
Publication number	US-10228370-B2
Application number	US-201715587907-A
Country	US
Kind code	B2
Filing date	May 5, 2017
Priority date	Nov 6, 2014
Publication date	Mar 12, 2019
Grant date	Mar 12, 2019

Abstract

The invention concerns variants of JL7 antigens that are suitable for detecting antibodies against Trypanosoma cruzi (causing Chagas disease) in an isolated biological sample. These antigens comprise a JL7 specific amino acid sequence, said JL7 specific sequence consisting of two copies of SEQ ID NO. 2, wherein each of said two copies has an amino acid identity of at least 90% to SEQ ID NO.2 and wherein no further Trypanosoma cruzi specific amino acid sequences are present in said polypeptide. The invention also concerns a composition of polypeptides useful for the detection of antibodies against Trypanosoma cruzi that comprises the above characterized JL7 antigen along with at least one of T. cruzi polypeptides 1F8, Cruzipain, KMP-11 and PAR-2. Moreover, it relates to a method for producing JL7 antigen as well as to diagnostic methods for detecting T. cruzi antibodies using the JL7 polypeptide. In addition, the invention concerns a reagent kit comprising said JL7 polypeptides or composition of Trypanosoma cruzi polypeptides.

First claim

The invention claimed is:

1. A polypeptide suitable for detecting antibodies against Trypanosoma cruzi in an isolated biological sample comprising Trypanosoma cruzi JL7 specific amino acid sequence consists of SEQ ID NO. 4, and wherein no further Trypanosoma cruzi specific amino acid sequences are present in said polypeptide.

2. A composition of polypeptides suitable for detecting antibodies against Trypanosoma cruzi antigens in an isolated biological sample comprising a polypeptide according to claim 1 and at least one Trypanosoma cruzi polypeptide selected from the group consisting of 1F8, Cruzipain, KMP-11 and PAR-2.

3. A reagent kit for the detection of anti- Trypanosoma cruzi antibodies, comprising a Trypanosoma cruzi JL7 polypeptide according to claim 1 or of a composition according to claim 2 .

Assignees

• Roche Diagnostics Operations Inc

Inventors

• Roessler Dieter
• Upmeier Barbara
• Zarnt Toralf

Classifications

• Y02A50/30

  Against vector-borne diseases, e.g. mosquito-borne, fly-borne, tick-borne or waterborne diseases whose impact is exacerbated by climate change · CPC title

• G01N33/564

  for pre-existing immune complex or autoimmune disease {, i.e. systemic lupus erythematosus, rheumatoid arthritis, multiple sclerosis, rheumatoid factors or complement components C1-C9} · CPC title

• C07K2319/21

  containing a His-tag · CPC title

• C07K2319/40

  containing a tag for immunodetection, or an epitope for immunisation · CPC title

• G01N2333/44

  from protozoa · CPC title