US 5,804,370 A · Early diagnosis of sepsis utilizing antigen-antibody interactions amplified by whole blood chemiluminescence

Abstract

The invention relates to a method for determining the extent of sepsis and/or an infection in a human or animal patient by detecting the amount of an antigen indicative of such infection. The amount of the antigen is detected in a patient blood derived test sample containing blood cell fractions. The method comprises: i) incubating the test sample with an amount of test antibodies specific to the antigen indicative of sepsis and/or infection to form antibody/antigen complexes; ii) allowing the antibody/antigen complexes to interact with the white blood cell fractions which results in the production of oxidants; iii) introducing to either steps i) or ii) a chemiluminescent compound to the test sample; iv) allowing the oxidants to react with the chemiluminescent compounds to emit luminescent light from the test sample; v) measuring the amount of emitted light over a predetermined period; and vi) correlating extent of sepsis and/or infection by comparison of the measured amount of emitted light of the test sample with measured amount of light emitted by a control sample which is treated the same as the test sample for steps i) to v) except that in step i) control antibodies are used which are of the same class as the test antibodies but are non-specific to the antigens indicative of infection.

Claims38

Dependent claims

A method for determining the presence or extent of an infection in a human or animal patient by determining the amount of a preselected antigen indicative of said infection in a sample of said patient's blood, said sample comprising plasma and white blood cells, said method sequentially comprising:

i) providing first and second aliquots of equal volume of said sample;
ii) reacting the first aliquot of said sample with an amount of test antibody sufficient to form an antigen/antibody complex with said antigen, wherein said test antibody specifically binds to said antigen, to provide a test sample;
iii) reacting the second aliquot of said sample with an equal amount of a control antibody wherein said control antibody (a) does not specifically bind said antigen and (b) is of the same class and species of origin as the test antibody, to provide a control sample;
iv) incubating the test and control samples for a time sufficient for the antigen/antibody complex to react with the white blood cells and the complement proteins in the plasma to produce oxidants;
v) contacting a chemiluminescent compound which reacts with said oxidants to generate luminscent light with either the test and control samples of steps ii) and iii) or with the test and control samples of step iv);
vi) measuring light emission over a predetermined time period;
and
vii) correlating differences in light emission between the test and control samples to the presence or amount of said antigen in said sample and thereby to the presence or extent of the infection in the patient.

5 more elements

A method for determining the presence or extent of sepsis in a human or animal patient by determining the amount of a preselected sepsis marker in a sample of said patient's blood, said sample comprising plasma and white blood cells, said method sequentially comprising:

i) providing first and second aliquots of equal volume of said sample;
ii) reacting the first aliquot of said sample with an amount of test antibody sufficient to form an antigen/antibody complex with said marker, wherein said test antibody specifically binds to said marker, to provide a test sample;
iii) reacting the second aliquot of said sample with an equal amount of a control antibody wherein said control antibody (a) does not specifically bind said marker and (b) is of the same isotype as the test antibody, to provide a control sample;
iv) incubating the test and control samples for a time sufficient for the antigen/antibody complex to react with the white blood cells and the complement proteins in the plasma to produce oxidants;
v) contacting a chemiluminescent compound which reacts with said oxidants to generate luminescen light with either the test and control samples of steps ii) and iii) or with the test and control samples of step iv);
vi) measuring light emission over a predetermined period;
and
vii) correlating differences in light emission between the test and control samples to the presence or amount of said marker in said sample and thereby to the presence or extent of the sepsis in the patient.

5 more elements

Dependencies are inferred from the claim text.

Early diagnosis of sepsis utilizing antigen-antibody interactions amplified by whole blood chemiluminescence

Life of this patent

Early diagnosis of sepsis utilizing antigen-antibody interactions amplified by whole blood chemiluminescence

Life of this patent

Abstract

Claims38