Abstract: Fusion polypeptides are disclosed which are substrates for Kutzneria albida transglutaminase. The fusion polypeptides comprise one or more FKBP chaperone(s) and a target polypeptide. Each of these elements is separated from the neighboring element by a linker amino acid sequence. It was found that inserting glutamic acid containing transglutaminase recognition motifs into the linker amino acid chains is advantageous. Subsequent labeling reactions catalyzed by the transglutaminase surprisingly provide labeled fusion polypeptides have superior properties when compared with chemically random-labeled fusion polypeptides of similar design. Assays and kits are provided for in vitro detection of target antibodies in samples.

Abstract: The present invention relates to a Corona antigen comprising a Corona nucleocapsid specific amino acid sequence, compositions, and reagent kits comprising the same and methods of producing it. Also encompassed are methods of detecting anti-Corona antibodies in samples using said Corona antigen, and methods of differential diagnosis of an immune response in a patient due to natural Corona infection or due to vaccination against Corona.

Abstract: The disclosure relates to a polypeptide suitable for detecting antibodies against a flavivirus in an isolated biological sample having a flavivirus NS1 wing domain specific amino acid sequence, wherein no amino acid sequences from the NS1 ?-ladder domain of said flavivirus are present in the polypeptide. In an embodiment, the flavivirus is selected from Zika virus (ZIKV), West-Nile virus (WNV), Dengue virus types 1-4 (DENV1-4), tick-borne encephalitis virus (TBEV), yellow fever virus (YFV) and Japanese encephalitis virus (JEV). Also disclosed is a method for producing said flaviviral NS1 wing domain specific polypeptides, a method for detecting antibodies specific for a first flavivirus species, the use of said flaviviral NS1 wing domain specific polypeptides for detecting antibodies as well as a reagent kit for detecting said flavivirus antibodies that has a flavivirus NS1 wing domain polypeptide.

Abstract: The disclosure relates to a polypeptide suitable for detecting antibodies against a flavivirus in an isolated biological sample having a flavivirus NS1 wing domain specific amino acid sequence, wherein no amino acid sequences from the NS1 ß-ladder domain of said flavivirus are present in the polypeptide. In an embodiment, the flavivirus is selected from Zika virus (ZIKV), West-Nile virus (WNV), Dengue virus types 1-4 (DENV1-4), tick-borne encephalitis virus (TBEV), yellow fever virus (YFV) and Japanese encephalitis virus (JEV). Also disclosed is a method for producing said flaviviral NS1 wing domain specific polypeptides, a method for detecting antibodies specific for a first flavivirus species, the use of said flaviviral NS1 wing domain specific polypeptides for detecting antibodies as well as a reagent kit for detecting said flavivirus antibodies that has a flavivirus NS1 wing domain polypeptide.

Abstract: The present description relates to a Corona antigen having a Corona nucleocapsid specific amino acid sequence, compositions, and reagent kits having the same and methods of producing it. Also encompassed are methods of detecting anti-Corona antibodies in samples using the Corona antigen, and methods of differential diagnosis of an immune response in a patient due to natural Corona infection or due to vaccination against Corona.

Abstract: The present invention relates to a Corona antigen comprising a Corona nucleocapsid specific amino acid sequence, compositions, and reagent kits comprising the same and methods of producing it. Also encompassed are methods of detecting anti-Corona antibodies in samples using said Corona antigen, and methods of differential diagnosis of an immune response in a patient due to natural Corona infection or due to vaccination against Corona.

Abstract: The disclosure relates to a polypeptide suitable for detecting antibodies against a flavivirus in an isolated biological sample having a flavivirus NS1 wing domain specific amino acid sequence, wherein no amino acid sequences from the NS1 ß-ladder domain of said flavivirus are present in the polypeptide. In an embodiment, the flavivirus is selected from Zika virus (ZIKV), West-Nile virus (WNV), Dengue virus types 1-4 (DENV1-4), tick-borne encephalitis virus (TBEV), yellow fever virus (YFV) and Japanese encephalitis virus (JEV). Also disclosed is a method for producing said flaviviral NS1 wing domain specific polypeptides, a method for detecting antibodies specific for a first flavivirus species, the use of said flaviviral NS1 wing domain specific polypeptides for detecting antibodies as well as a reagent kit for detecting said flavivirus antibodies that has a flavivirus NS1 wing domain polypeptide.