Immunoassay platform for the serological discrimination of closely related viruses
An immunoassay platform and methodology are described for discriminatively detecting target microorganism antibodies to a target antigen in a biological sample derived from a host animal, from among antibodies of cross-reactively-related microorganism(s) potentially present in the biological sample, by use of contemporaneous assays conducted with and without blocking antibodies exogenous to the host animal. Attenuation of detection reagent signal between the contemporaneous assays may be used to determine a target antigen previously infected or non-infected status of the host animal. An assay system is described, including: a single-use cartridge containing test strips constituted to perform the immunoassay; an integrated sample collection and processing device engageable with the single-use cartridge for delivery of sample thereto, and for operatively initiating immunoassay performance in the single-use cartridge; and a portable immunoassay reader for reading immunoassay output signals from the test strips of the single-use cartridge.
1. An immunoassay for discriminating human antibodies specific for a target virus from human cross-reacting antibodies to related viruses in a single sample, wherein the target virus comprises a flavivirus, a coronavirus, a herpes virus, an influenza virus, or a hepatitis virus, the immunoassay comprising:
(a) immobilizing target virus antigens on each of a first immunoassay substrate and a second immunoassay substrate,
(b) introducing corresponding amounts of the sample to each of the first immunoassay substrate and the second immunoassay substrate on which the target virus antigens have been immobilized;
(c) (i) introducing non-human antibodies against the target virus antigens to the first immunoassay substrate and introducing a blank solution to the second immunoassay substrate,
or alternatively,
(ii) providing the first immunoassay substrate with the non-human antibodies preloaded thereon, with or without introducing a blank solution to the second immunoassay substrate,
so that the non-human antibodies against the target virus antigens compete with human antibodies in the sample to bind with the immobilized target virus antigens on the first immunoassay substrate, and human antibodies of the sample bind with the immobilized target virus antigens on the second immunoassay substrate in the absence of the non-human antibodies;
(d) introducing a human antibody detection reagent to each of the first and second immunoassay substrates wherein the human antibody detection reagent binds to human antibodies that remain on the first immunoassay substrate and the second immunoassay substrate; and
(e) generating a first output signal correlative of a first amount of human antibodies bound with target virus antigens immobilized on the first immunoassay substrate and generating a second output signal correlative of a second amount of human antibodies bound with target virus antigens immobilized on the second immunoassay substrate,
wherein a predetermined higher difference level between the first and second output signals contraindicate the presence of antibodies to target virus, and a predetermined lower difference level between the first and second output signals indicate the presence of antibodies to the target virus.
2. The immunoassay of claim 1 , wherein the immunoassay is conducted to determine infection by the target virus of a human from whom the sample is derived.
3. The immunoassay of claim 1 , wherein the human antibodies are immunoglobulin G, M, A, D or E.
4. The immunoassay of claim 1 , wherein the immunoassay is conducted to determine prior infection by the target virus of a human from whom the sample is derived.
5. The immunoassay of claim 1 , wherein the immunoassay is conducted to determine immunogenicity of a target virus vaccine.
6. The immunoassay of claim 1 , wherein measurements of human antibodies against the target virus antigen are quantitative, semi-quantitative, or qualitative.
7. The immunoassay of claim 1 , wherein the immunoassay is conducted on a lateral flow immunoassay platform.
8. The immunoassay of claim 1 , wherein the immunoassay is conducted on an ELISA immunoassay platform.
9. The immunoassay of claim 1 , wherein the immunoassay is conducted on a microparticle enzyme immunoassay platform.
10. The immunoassay of claim 1 , wherein the sample comprises whole blood.
11. The immunoassay of claim 1 , wherein the sample comprises serum.
12. The immunoassay of claim 1 , wherein the sample comprises plasma.
13. The immunoassay of claim 1 , wherein the sample comprises saliva.
14. The immunoassay of claim 1 , wherein the sample comprises urine.
15. The immunoassay of claim 1 , wherein the human antibody detection reagent comprises optical probes.
16. The immunoassay of claim 13 , wherein the optical probes comprise gold particles, colored latex particles, enzymes, fluorescent dyes, fluorescent particles, or phosphorescent dye.
17. The immunoassay of claim 1 , wherein the human antibody detection reagent comprises electrochemical probes or magnetic probes.
18. The immunoassay of claim 1 , wherein the substrates comprise particles, plates, membranes, papers, glass beads, or microfluidic devices.
19. The immunoassay of claim 1 , wherein the flavivirus comprises Dengue virus, Zika virus, West Nile virus, or Yellow Fever virus.
20. An immunoassay for discriminating non-human antibodies specific for a target virus from non-human cross-reacting antibodies to related viruses in a single sample, wherein the target virus comprises a flavivirus, a coronavirus, a herpes virus, an influenza virus, or a hepatitis virus, the immunoassay comprising:
(a) immobilizing target virus antigens on each of a first immunoassay substrate and a second immunoassay substrate,
(b) introducing the non-human sample comprising antibodies to each of the first immunoassay substrate and the second immunoassay substrate on which the target virus antigens have been immobilized;
(c) (i) introducing blocking antibodies of origins other than the non-human species against target virus antigens to the first immunoassay substrate and introducing a blank solution to the second immunoassay substrate,
or alternatively,
(ii) providing the first immunoassay substrate with blocking antibodies preloaded thereon, with or without introducing a blank solution to the second immunoassay substrate,
so that the blocking antibodies compete with the non-human species antibodies in the non-human species sample to bind with the immobilized target virus antigens on the first immunoassay substrate, and the non-human species antibodies of the non-human species sample bind with the immobilized target virus antigens on the second immunoassay substrate in the absence of the blocking antibodies;
(d) introducing a non-human species antibody detection reagent to each of the first and second immunoassay substrates, wherein the non-human species antibody detection reagent binds to non-human species antibody that remain on the first immune assay substrate and the second immunoassay substrate; and
(e) generating a first output signal correlative of a first amount of non-human antibodies bound with target virus antigens immobilized on the first immunoassay and generating a second output signal correlative of a second amount of non-human antibodies bound with target virus antigens immobilized on the second immunoassay,
wherein a predetermined higher difference level between the first and second output signals contraindicates the presence of non-human antibodies to target virus, and a predetermined lower difference level between the first and second output signals indicates the presence of non-human antibodies to the target virus.