A method for making a population of cells that are highly sensitive to clostridial neurotoxin, the method comprising: (a) contacting recombinant cells that express an indicator protein with clostridial neurotoxin; and (b) following such contact, selecting the cells that exhibit cleavage of the indicator protein. A cell from the population produced using the aforementioned method. An assay for determining the activity of a modified or recombinant neurotoxin comprising contacting such a cell with the modified or recombinant neurotoxin under conditions and for a period of time sufficient to allow the protease domain of a wild-type clostridial neurotoxin to cleave the indicator protein in the cell and determining the presence of product resulting from the cleavage of the indicator protein.

The present invention is related to a method for detecting and identifying protein-protein or protein-small molecule interactions using a bait and prey system. It is also related to bait and prey proteins, small molecules and constructs that are used for the methods described herein.

The present invention relates to a prostate-specific membrane antigen (PSMA)-specific binding protein, wherein the PSMA-specific binding protein is a lipocalin 2 (Lcn2)-derived binding protein and binds to PSMA with a K.sub.D of 10 nM or lower. The present invention also relates to a nucleic acid molecule encoding the PSMA-specific binding protein of the invention, a vector comprising said nucleic acid molecule of the invention and a host cell transformed with the vector. Furthermore, the invention relates to a method of producing the PSMA-specific binding protein of the invention, the method comprising culturing the host cell of the invention under suitable conditions and isolating the PSMA-specific binding protein produced. The present invention further relates to a protein conjugate comprising the PSMA-specific binding protein of the invention, or the PSMA-specific binding protein produced by the method of the invention. In addition, the present invention relates to a pharmaceutical or diagnostic composition; to the PSMA-specific binding protein of the invention, the nucleic acid molecule of the invention, the vector of the invention, the host cell of the invention or the PSMA-specific binding protein produced by the method of the invention, for use in therapy and/or diagnosis, and in particular for use in the therapy and/or diagnosis of tumors, Crohn's disease and/or neurological diseases.

The present invention relates to a fusion protein comprising: —a N-terminal domain which comprises an antibody which is a variable domain of a camelid heavy-chain antibody (VHH) or a single chain variable fragment (scFV) and which is directed against an immunoglobulin and —a C-terminal domain which comprises a polypeptide with a luciferase activity: —having the amino acid sequence SEQ ID NO: 1 or —having at least 80% amino acid sequence identity to the amino acid sequence SEQ ID NO: 1.

The present invention provides novel allergens isolated from grass carp Ctenopharyngodon idella, recombinant or modified polypeptides comprising such allergens, nucleic acids encoding the polypeptides as well as related compositions. Also provided are methods and kits for diagnosing fish allergy.

The invention relates to a sensor molecule for detecting a target molecule comprising: (a) a rod-like molecule L and a rod-like molecule R connected to each other by a joint molecule C to form a hinge; (b) a target binding molecule A bonded to the end of rod-like molecule L opposite to the joint molecule C; (c) a binding molecule A′ bonded to the end of rod-like molecule R opposite the joint molecule C; wherein the target binding molecule A is arranged to bind to the target molecule to be detected, and binding molecule A′ is arranged to bind to: i) the same target molecule as target binding molecule A; or ii) a complex of the target binding molecule A and the target; and wherein the hinge is biased into an open position, such that target binding molecule A and binding molecule A′ are biased apart by the hinge.

The screening method of the present invention is useful for screening drugs such as insulin secretagogues having an insulin secretagogue activity with minimized side effects (hypoglycemia induction, etc.). The transformant in which a polynucleotide encoding the fusion protein used for the screening method is introduced, the screening kit comprising the transformant, etc. are also useful for screening excellent drugs.

The present disclosure provides an anti-biotin antibody, and provides an amino acid sequence encoding the CDRs of the antibody. Studies have shown that the antibody only reacts with a biotin conjugate or derivative, and does not react with free biotin. The present disclosure further provides applications of the antibody in, including but not limited to, ELISA, cell capture, sorting and enrichment, western blotting, flow cytometry, immunocytofluorescent staining, and immunohistochemistry. The anti-biotin antibody conjugated immunomagnetic beads can specifically and directly recognize a biotin labeled antigen, and do not bind to free biotin which is often presented in clinical samples and culture media. In addition, the anti-biotin antibody-conjugated magnetic beads or anti-biotin antibody-fluorescein provide an ideal solution for the isolation of specific cells, and can even enrich and separate target cells from samples rich in debris or other rare biological materials.

Compositions and immunoassays for detecting SARS-CoV-2 antigen-specific antibodies in a biological sample are provided. The compositions are antigens from SARS-CoV-2 such as the proteins N, M, S, S1, S2′, NSP1, ORF3a, ORF3b, ORF7a, ORF7b and ORF8, fused to a light emitting protein. The compositions are useful in immunoassays for detecting antibodies to the SARS-CoV-2 antigens. A preferred immunoassay is the luciferase immunoprecipitation systems (LIPS) to detect SARS-CoV-2 antigen-specific antibodies with high sensitivity and specificity. The current or present exposure or infection with SARS-CoV-2 can be detected and/or diagnosed using the disclosed compositions and methods. Typically, the presence and/or elevated amount of SARS-CoV-2 antibodies in the individual’s biological sample compared to a control is indicative of current or past exposure or infection with SARS-CoV-2 as discussed herein.

The present disclosure provides conjugates and systems for modulating the activity of a ligand-binding polypeptide such as a D1 dopamine receptor. The present disclosure provides methods of modulating the activity of a D1 dopamine receptor. The present disclosure provides methods of treating Parkinson’s disease in an individual.