The present disclosure relates to a method for measuring aggregation of low-density lipoprotein (LDL). The susceptibility of LDL to aggregate is an important factor regarding prognosis, diagnosis and surveillance of atherosclerotic cardiovascular diseases and cardiometabolic diseases, such as type 2 diabetes and related conditions, at various stages of their development. Also provided are methods of treatment of such diseases in subjects in need thereof.

The present disclosure relates to a method for measuring aggregation of low-density lipoprotein (LDL). The susceptibility of LDL to aggregate is an important factor regarding prognosis, diagnosis and surveillance of atherosclerotic cardiovascular diseases and cardiometabolic diseases, such as type 2 diabetes and related conditions, at various stages of their development. Also provided are methods of treatment of such diseases in subjects in need thereof.

This invention provides a method for quantifying cholesterol in small, dense LDL in two steps using an autoanalyzer without pretreatment of an analyte, wherein spontaneous color development of a reagent during storage is suppressed, a kit for quantification used in the method, and a method for preparing such kit. The kit for quantification of cholesterol in small, dense LDL in a sample obtained from a subject used in the method for quantifying cholesterol in small, dense LDL in two steps comprises: (1) a first reagent composition having cholesterol esterase activity, cholesterol oxidase activity, and sphingomyelinase activity and leading cholesterol in lipoproteins other than small, dense LDL to the outside of the reaction system in the presence of cholesterol esterase activity, cholesterol oxidase activity, and sphingomyelinase activity; and (2) a second reagent composition for quantifying cholesterol in small, dense LDL, wherein a coupler, an iron complex, and peroxidase activity are not allowed to be present in the same reagent composition, which is either the first reagent composition or the second reagent composition.

Reagents, assays, methods, kits, devices, and systems for rapid measurement of cholesterol and cholesterol sub-fractions from a blood sample are provided. Total cholesterol, low density lipoprotein cholesterol, and high density lipoprotein cholesterol can be measured in a single assay using kinetic measurements, under conditions in which cholesterol sub-species are converted to a detectable product at distinct rates. The detectable product is measured at different times after assay initiation. A lipase, cholesterol esterase, cholesterol oxidase and a peroxidase may be used together to produce colored product in amounts directly proportional to the quantity of cholesterol converted. Methods for calculating very-low density lipoprotein cholesterol levels by further including triglyceride measurements are disclosed. Assays may be performed in a single reaction mixture, allowing more accurate and precise cholesterol determinations, including ratios of cholesterol sub-fractions to total cholesterol, at less expense, than would be expected by performing several different assays in different reaction mixtures.

Reagents, assays, methods, kits, devices, and systems for rapid measurement of cholesterol and cholesterol sub-fractions from a blood sample are provided. Total cholesterol, low density lipoprotein cholesterol, and high density lipoprotein cholesterol can be measured in a single assay using kinetic measurements, under conditions in which cholesterol sub-species are converted to a detectable product at distinct rates. The detectable product is measured at different times after assay initiation. A lipase, cholesterol esterase, cholesterol oxidase and a peroxidase may be used together to produce colored product in amounts directly proportional to the quantity of cholesterol converted. Methods for calculating very-low density lipoprotein cholesterol levels by further including triglyceride measurements are disclosed. Assays may be performed in a single reaction mixture, allowing more accurate and precise cholesterol determinations, including ratios of cholesterol sub-fractions to total cholesterol, at less expense, than would be expected by performing several different assays in different reaction mixtures.

The invention provides an enzymatic method for measuring the concentration of one or more analytes in the plasma portion of a blood derived sample, containing a first and a second component, where said second component interferes with the measurement of said first component. The method includes: i) diluting the sample with a reagent mixture; ii) substantially removing blood cells; iii) using a reagent which serves to temporarily prevent reaction of the second component, to generate a blocked second component; iv) causing the selective reaction of a constituent of each analyte to directly or indirectly generate detectable reaction products, where one of the analytes is the first component; v) monitoring the detectable reaction product or products; vi) relating an amount of the detectable product or products and/or a rate of formation of the detectable product or products to the concentration of each analyte, where the concentration of at least the first component is related to a corresponding detectable reaction product by means of estimating an un-measurable (fictive) endpoint. Step iii) may be carried out at any stage up to and including step iv) but before steps v) or vi). The reagent of step iii) may be applied to the sample separately or may be included in a reagent mixture during steps i) or iv). A corresponding kit is also provided.

The invention provides an enzymatic method for measuring the concentration of one or more analytes in the plasma portion of a blood derived sample, containing a first and a second component, where said second component interferes with the measurement of said first component. The method includes: i) diluting the sample with a reagent mixture; ii) substantially removing blood cells; iii) using a reagent which serves to temporarily prevent reaction of the second component, to generate a blocked second component; iv) causing the selective reaction of a constituent of each analyte to directly or indirectly generate detectable reaction products, where one of the analytes is the first component; v) monitoring the detectable reaction product or products; vi) relating an amount of the detectable product or products and/or a rate of formation of the detectable product or products to the concentration of each analyte, where the concentration of at least the first component is related to a corresponding detectable reaction product by means of estimating an un-measurable (fictive) endpoint. Step iii) may be carried out at any stage up to and including step iv) but before steps v) or vi). The reagent of step iii) may be applied to the sample separately or may be included in a reagent mixture during steps i) or iv). A corresponding kit is also provided.

Disclosed are a method and a reagent for quantifying HDL3 in a test sample without requiring laborious operations. The method for quantifying cholesterol in high-density lipoprotein 3 comprises reacting a test sample with one or more surfactants which react specifically with high-density lipoprotein 3, and quantifying cholesterol. When one surfactant is used, the surfactant is one selected from the group consisting of polyoxyethylene polycyclic phenyl ethers having an HLB of 12.5 to 15. When two or more surfactants are used, at least one of the surfactants is at least one selected from the group consisting of polyoxyethylene polycyclic phenyl ethers, and the two or more surfactants are combined so as to provide the total HLB of 12.5 to 15 of the combined surfactants.

Disclosed are a method and a reagent for quantifying HDL3 in a test sample without requiring laborious operations. The method for quantifying cholesterol in high-density lipoprotein 3 comprises reacting a test sample with one or more surfactants which react specifically with high-density lipoprotein 3, and quantifying cholesterol. When one surfactant is used, the surfactant is one selected from the group consisting of polyoxyethylene polycyclic phenyl ethers having an HLB of 12.5 to 15. When two or more surfactants are used, at least one of the surfactants is at least one selected from the group consisting of polyoxyethylene polycyclic phenyl ethers, and the two or more surfactants are combined so as to provide the total HLB of 12.5 to 15 of the combined surfactants.

The invention provides an enzymatic method for measuring the concentration of one or more analytes in the plasma portion of a blood derived sample, containing a first and a second component, where said second component interferes with the measurement of said first component. The method includes: i) diluting the sample with a reagent mixture; ii) substantially removing blood cells; iii) using a reagent which serves to temporarily prevent reaction of the second component, to generate a blocked second component; iv) causing the selective reaction of a constituent of each analyte to directly or indirectly generate detectable reaction products, where one of the analytes is the first component; v) monitoring the detectable reaction product or products; vi) relating an amount of the detectable product or products and/or a rate of formation of the detectable product or products to the concentration of each analyte, where the concentration of at least the first component is related to a corresponding detectable reaction product by means of estimating an un-measurable (fictive) endpoint. Step iii) may be carried out at any stage up to and including step iv) but before steps v) or vi). The reagent of step iii) may be applied to the sample separately or may be included in a reagent mixture during steps i) or iv). A corresponding kit is also provided.