Disclosed herein are expression vectors which display a passenger polypeptide on the outer surface of a biological entity. As disclosed herein the displayed passenger polypeptide is capable of interacting or binding with a given ligand. Also disclosed are methods of making and using the expression vectors. N/C terminal fusion expression vectors and methods of making and using are also disclosed.

This disclosure describes, in one aspect, a method for identifying β-glucan binding to immune cells of a subject. Generally, the method includes obtaining a blood sample from the subject, the blood sample comprising immune cells, adding soluble β-glucan to at least a portion of the blood sample and incubating the mixture under conditions allowing the soluble β-glucan to bind to the immune cells, and detecting soluble β-glucan bound to the immune cells. In another aspect, this disclosure describes a method that generally includes identifying the subject as a low binder of β-glucan, and co-administering to the subject a soluble β-glucan and an antibody preparation capable of converting the subject from a low binder to a high binder.

This disclosure describes, in one aspect, a method for identifying β-glucan binding to immune cells of a subject. Generally, the method includes obtaining a blood sample from the subject, the blood sample comprising immune cells, adding soluble β-glucan to at least a portion of the blood sample and incubating the mixture under conditions allowing the soluble β-glucan to bind to the immune cells, and detecting soluble β-glucan bound to the immune cells. In another aspect, this disclosure describes a method that generally includes identifying the subject as a low binder of β-glucan, and co-administering to the subject a soluble β-glucan and an antibody preparation capable of converting the subject from a low binder to a high binder.

An immunoassay includes forming first mixtures by reacting a combination reagent with serum of a subject; simultaneously forming second mixtures by reacting randomly selected platelet samples with the serum wherein in each mixture there are immunity compounds formed by combining the platelet antigens with predetermined antibodies in the serum, and other platelet antigens and other antibodies in the serum not forming the immunity compounds; preparing an interception device including receptacles and a filter net; placing each mixture in one receptacle; washing the mixtures wherein the mixtures forming the immunity compounds are intercepted by the filter net with others passing through; adding a signal sensing reagent to each receptacle; reacting the signal sensing reagent with the intercepted mixtures forming the immunity compounds to form final products; and performing a signal sensing to determine whether the final products contain anti-platelet antibodies and determine compatibility of cross matching of respective platelet samples.

An immunoassay includes forming first mixtures by reacting a combination reagent with serum of a subject; simultaneously forming second mixtures by reacting randomly selected platelet samples with the serum wherein in each mixture there are immunity compounds formed by combining the platelet antigens with predetermined antibodies in the serum, and other platelet antigens and other antibodies in the serum not forming the immunity compounds; preparing an interception device including receptacles and a filter net; placing each mixture in one receptacle; washing the mixtures wherein the mixtures forming the immunity compounds are intercepted by the filter net with others passing through; adding a signal sensing reagent to each receptacle; reacting the signal sensing reagent with the intercepted mixtures forming the immunity compounds to form final products; and performing a signal sensing to determine whether the final products contain anti-platelet antibodies and determine compatibility of cross matching of respective platelet samples.

The present invention relates to an inert carrier Salmonella and potential use thereof, which is expected to be developed into a new inert carrier bacteria, and can be applied to the development of an indirect agglutination test method for simple and rapid detection of antigens or infected antibodies. The inert carrier Salmonella has been deposited in CGMCC in Beijing on Mar. 18, 2019 with the accession number of CGMCC No. 17340, and is classified as Salmonella sp. with a strain code of S9. The Salmonella has no visible agglutination reaction with various chicken sera derived from different genetic backgrounds, i.e., it has no non-specific agglutination reaction with chicken sera derived from broad range of genetic backgrounds.

Provided herein is a method and system for analyzing a sample. In some embodiments the method makes use of a plurality of capture agents that are each linked to a different oligonucleotide and a corresponding plurality of labeled nucleic acid probes, wherein each of the labeled nucleic acid probes specifically hybridizes with only one of the oligonucleotides. The sample is labeled with the capture agents en masse, and sub-sets of the capture agents are detected using iterative cycles using corresponding subsets of the labeled nucleic acid probes.

Provided herein is a method and system for analyzing a sample. In some embodiments the method makes use of a plurality of capture agents that are each linked to a different oligonucleotide and a corresponding plurality of labeled nucleic acid probes, wherein each of the labeled nucleic acid probes specifically hybridizes with only one of the oligonucleotides. The sample is labeled with the capture agents en masse, and sub-sets of the capture agents are detected using iterative cycles using corresponding subsets of the labeled nucleic acid probes.

The present disclosure provides methods for the detection of target specific antibodies in samples. The methods include the detection of pathogen-specific antibodies, such as SARS-CoV-2 specific antibodies. Also included is a kit for use for the detection of pathogen specific antibodies in a sample. In one aspect, the disclosure provides a method of detecting the presence of a target specific antibody in a sample by (i) contacting the sample with a test cell comprising one or more exogenous nucleic acid sequences encoding one or more target proteins; and (ii) detecting the presence of the target specific antibody in the sample by contacting the immune complex of (i) with an anti-immunoglobulin (Ig) antibody, and detecting the anti-immunoglobulin (Ig) antibody, thereby detecting the presence of a target specific antibody.

An apparatus for assaying biofluid includes a receptacle for removably housing a set of cuvettes of a biofluid sample dispensing apparatus, each cuvette of the set of cuvettes containing an assay sample having a reagent and a sample of the biofluid; a receptacle sealing element disposed around the receptacle for providing sealing engagement between the receptacle and the biofluid sample dispensing apparatus for sealing the set of cuvettes within the receptacle; a vacuum source for evacuating the receptacle; and an automated assay system connected to the receptacle for performing an assay process on the assay samples in the set of cuvettes, while maintaining the set of cuvettes within the receptacle.