NEW HORIZONS IN IMMUNOASSAY
a report for
'Clinica World Medical Device & Diagnostic News'
TABLE OF CONTENTS
CHAPTER 1: INTRODUCING IMMUNOASSAYS ........................1
1.1 Scope of this Report. ................................1
1.2 Definitions and Abbreviations. .......................2
1.3 Why Immunoassay? .....................................5
1.3.1 Technical Advantages of Immunoassays. ...........5
1.3.2 Commercial Advantages of Immunoassays. ..........6
1.4 Basic Concepts in Immunoassay. .......................6
1.4.1 Introduction. ...................................6
1.4.2 Antibodies. .....................................7
1.4.2.1 Introduction. ...............................7
1.4.2.2 Structure of Antibodies. ....................8
1.4.2.3 Antibody Diversity and its Significance. ....9
1.4.2.4 Monoclonal Antibodies. .....................10
1.4.2.4.1 Introduction. .........................10
1.4.2.4.2 Preparation of Monoclonal
Antibodies.............................10
1.4.2.4.3 Use of Flow Sorters in Hybridoma
Screening..............................12
1.4.2.4.4 Recent Progress in Hybridoma
Technology.............................12
1.4.2.4.5 The Monoclonal Antibody Market. .......13
1.4.2.4.6 Advantages and Disadvantages of
Monoclonal Antibodies in Diagnostic
Immunoassay Kits.......................13
1.4.2.4.7 Conclusions. ..........................16
1.4.2.5 Single-Domain Antibodies. ..................17
1.4.3 The Bound-Free Separation Step. ................18
1.4.3.1 The Role of Centrifugation. ................18
1.4.3.2 Fractional Precipitation. ..................19
1.4.3.3 Charcoal Separation. .......................19
1.4.3.4 Double Antibody Separation. ................20
1.4.3.5 Solvent Separation. ........................20
1.4.3.6 Solid Phase Separation. ....................20
1.4.3.6.1 Introduction. .........................20
1.4.3.6.2 Magnetic Solid Phases. ................20
1.4.3.6.3 Solvent Density Separation. ...........21
1.4.3.6.4 Cartridge-Enclosed Solid Phases. ......21
1.4.3.6.5 Tubes, Plates, and Beads. .............21
1.4.3.6.6 Common-Capture Solid Phases. ..........22
1.4.3.7 Nonseparation Immunoassays. ................23
1.4.4 Immunoassay Labels. ............................24
1.4.4.1 Precipitation Immunoassays. ................24
1.4.4.2 Radioactive Labels. ........................24
1.4.4.3 Nonisotopic Labels. ........................26
1.4.4.3.1 Advantages. ...........................26
1.4.4.3.2 Overview of Nonisotopic Labels. .......27
1.4.5 Immunoassay Designs. ...........................30
1.4.5.1 Competitive Immunoassays. ..................30
1.4.5.2 Immunometric or Excess-Reagent
Immunoassays................................31
1.4.5.2.1 Introduction. .........................31
1.4.5.2.2 Types of Excess-Reagent Assay. ........31
1.4.5.2.3 Characteristics of Excess-Reagent
Assays.................................31
1.4.5.2.4 Immunometric Assays for Small
Molecules..............................32
1.4.6 Assay Detection Limits and Sensitivities. ......33
1.4.6.1 Isotopic versus Nonisotopic
Methodologies...............................33
1.4.6.2 Definitions and Calculation. ...............33
1.4.6.3 Practical Measurement of Assay
Sensitivities...............................34
1.4.6.4 How Sensitive Must Assays Be? ..............35
1.4.7 Accuracy and Standardisation. ..................36
1.4.7.1 Matrix Effects, Bias, and Imprecision. .....36
1.4.7.2 Standardisation. ...........................36
1.4.8 Precision Goals for Clinical Immunoassays. .....37
1.4.9 Data Reduction and Quality Control. ...........38
1.4.9.1 Introduction. ..............................38
1.4.9.2 Assay Replication. .........................39
1.4.9.3 Reporting the Results. .....................40
1.4.9.4 Computerised Data Reduction. ...............40
1.4.9.4.1 General Considerations. ...............40
1.4.9.4.2 Curve-Fitting. ........................40
1.5. Expert Systems in Immunoassay. .....................42
1.5.1 The Need For Expert Systems. ...................42
1.5.2 What is an Expert System? ......................43
1.5.3 How Expert Systems Might be Deployed. ..........43
1.5.4 Current Availability of Expert Systems. ........44
CHAPTER 2: IMMUNOASSAYS USING ENZYME LABELS................45
2.1 Introduction........................................45
2.1.1 Advantages of EIA. .............................45
2.1.2 Basic Assay Configurations used in EIA. ........45
2.2 Heterogeneous Enzymeimmunoassays. ...................46
2.2.1 Overview. ......................................46
2.2.1 Labels Used in EIAs. ...........................46
2.2.2 Survey of EIA Manufacturers. ...................47
2.2.2.1 Abbott Laboratories. .......................47
2.2.2.2 Amersham International. ....................48
2.2.2.3 Becton Dickinson. ..........................49
2.2.2.4 Behringwerke. ..............................50
2.2.2.5 Boehringer Mannheim. .......................50
2.2.2.6 Dade. ......................................51
2.2.2.7 Eastman Kodak. .............................52
2.2.2.8 Hybritech. .................................52
2.2.2.8.1 Tandem Coated Bead System. ............53
2.2.2.8.2 Tandem ICON System. ...................54
2.2.2.9 Immunodiagnostic Systems (IDS). ............55
2.2.2.10 Novo BioLabs. .............................56
2.2.2.10.1 Chemelia System. .....................56
2.2.2.10.2 AELIA Enzyme Amplification System. ...56
2.2.2.10.3 OVEIA Dual Analyte Assay. ............57
2.2.2.11 Serono Diagnostics. .......................58
2.2.2.12 Walker Laboratories .......................60
2.2.2.13 Other Manufacturers. ......................60
bioMerieux ................................61
International CIS .........................61
Diagnostic Products Corporation (DPC) .....61
DRG Corporation ...........................61
DuPont ....................................61
PB Diagnostic Systems .....................61
Roche .....................................62
Sorin Biomedica ...........................62
Wellcome Diagnostics ......................62
2.3 Homogeneous Enzyme Immunoassays. ....................63
2.3.1 Advantages and Limitations. ....................63
2.3.2 Basic Principles. ..............................63
2.3.3 Survey of Homogeneous EIA Methods. .............64
2.3.3.1 EMIT. ......................................64
2.3.3.2 Enzyme Modulator Mediated Immunoassay
(EMMIA).....................................65
2.3.3.3 Apoenzyme Reactivation Immunoassay
System (ARIS). .............................65
2.3.3.4 Enzyme Channelling Immunoassay (ECIA). .....66
2.3.3.5 Enzyme Enhancement Immunoassay (EEIA). .....66
2.3.3.6 Cloned Enzyme Donor Immunoassay (CEDIA). ...67
2.3.3.7 Substrate-Labelled Fluorescent Enzyme
Immunoassay (SLFEIA)........................67
CHAPTER 3: ASSAYS USING FLUORESCENT AND LUMINESCENT
LABELS..........................................68
3.1 Introduction to Fluorescence and Luminescence. ......68
3.2 Fluoroimmunoassays and Immunofluorometric Assays. ...69
3.2.1 Chemistry of Fluorescent Labels. ...............69
3.2.2 Assay Configurations in FIA. ...................70
3.2.3 Survey of FIA Manufacturers. ...................70
3.2.3.1 Abbott Laboratories. .......................70
3.2.3.2 CyberFluor. ................................72
3.2.3.3 Pharmacia LKB. .............................72
3.2.3.4 PB Diagnostics. ............................74
3.2.3.5 Syva Company. ..............................74
3.2.3.6 Other Manufacturers. .......................75
Becton Dickinson ...........................75
American Dade ..............................75
DuPont .....................................75
Roche.......................................75
3.2.3.7 Other Fluorescent Homogeneous
Immunoassays................................76
3.2.3.7.1 Fluorescence Enhancement
Immunoassays...........................76
3.2.3.7.2 Indirect Quenching FIAs. ..............76
3.2.3.7.3 Release FIAs. .........................76
3.3 Luminescent Immunoassays. ...........................77
3.3.1 Introduction. ..................................77
3.3.2 Bioluminescence and Chemiluminescence. .........77
3.3.3 Assay Configurations using Luminescent
Labels..........................................77
3.3.4 Survey of Commercial LIA Systems. ..............78
CHAPTER 4: OTHER IMMUNOASSAY TECHNOLOGIES..................80
4.1 Introduction. ........................................80
4.2 Particle Counting Immunoassay (PACIA). ..............80
4.3 Enzyme Radioimmunoassay. ............................81
4.4 Scintillation Proximity Immunoassay. ................81
4.5 Metalloimmunoassay. .................................82
4.6 Spin Immunoassay. ...................................82
4.7 Liposome Immunoassay. ...............................83
4.8 Idiotype/Anti-Idiotype Immunoassays. ................84
4.9 Substrate-Leash Amplification Immunoassay. ..........85
4.10 Partition Affinity Ligand Immunoassay. .............85
CHAPTER 5: IMMUNOSENSORS ..................................87
5.1 Introduction. .......................................87
5.2 Types of Immunosensor. ..............................87
5.3 Survey of Immunosensor Research and Development. ....88
5.3.1 Optical Immunosensors. .........................88
5.3.1.1 Surface Plasmon Resonance. .................88
5.3.1.2 Evanescent Wave Immunoassay. ...............88
5.3.1.3 Fluorescence Capillary-Fill Immunoassay. ...89
5.3.2 Acoustic Immunosensors. ........................90
5.3.2.1 Surface Acoustic Wave Immunoassay. .........90
5.3.2.2 Piezoelectic Oscillation Immunoassay. ......91
5.3.3 Semiconductor Immunosensors. ...................91
5.3.3.1 Field-Effect Transistors. ..................91
5.3.3.2 Thermometric Immunoassays. .................91
5.3.4 Electrochemical Immunosensors. .................92
5.3.4.1 Direct Potentiometric Sensors. .............92
5.3.4.2 Indirect Potentiometric Sensors. ...........92
5.3.4.3 Indirect Amperometric Sensors. .............93
CHAPTER 6: INSTRUMENTATION IN IMMUNOASSAY..................95
6.1 Introduction. .......................................95
6.2 Gamma Counters. .....................................95
6.3 Scintillation Counters. .............................96
6.4 Nephelometers. ......................................96
6.5 Spectrophotometers. .................................97
6.5.1 General Description. ...........................97
6.5.2 Benchtop Spectrophotometers. ...................97
6.5.3 Clinical Chemistry Analysers. ..................98
6.5.4 Reflectance Photometers. .......................98
6.5.5 Survey of Spectrophotometric Immunoassay
Analysers.......................................98
Abbott Laboratories ............................98
Becton Dickinson ...............................99
Behring ........................................99
Boehringer Mannheim ............................99
Dynatech Laboratories...........................99
Flow Laboratories .............................100
Hybritech .....................................100
Labsystems ....................................100
Molecular Devices .............................100
Olympus .......................................100
Roche .........................................100
Serono ........................................101
Syva Company ..................................101
6.6 Fluorometric Instrumentation. ......................101
6.6.1 General Description. ..........................101
6.6.2 Survey of Fluorometric Immunoassay
Instrumentation................................102
Abbott Laboratories ...........................102
Becton Dickinson ..............................102
CyberFluor ....................................102
American Dade .................................102
Flow Laboratories .............................103
Hybritech .....................................103
Pandex ........................................103
Pharmacia-LKB .................................103
6.7 Luminometric Instrumentation. ......................103
Amersham ......................................103
Ciba-Corning ..................................103
Hamilton Bonaduz ..............................104
Henning .......................................104
Mallinckrodt ..................................104
Others ........................................104
CHAPTER 7: THE APPLICATIONS OF IMMUNOASSAYS ..............105
7.1 Introduction. ......................................105
7.2 Thyroid Function Testing. ..........................105
7.2.1 Overview of Thyroid Physiology. ...............105
7.2.2 Immunoassays in the Management of Thyroid
Disease........................................106
7.2.2.1 T3 and T4 Assays. .........................106
7.2.2.2 TSH Assays. ...............................107
7.2.2.3 Monitoring Thyroxine Therapy. .............107
7.2.3 The Measurement of Free Thyroid Hormones. .....108
7.2.3.1 Equilibrium Dialysys. .....................108
7.2.3.2 Commercial Kit Methods. ...................108
7.2.3.3 Analytical Problems with Labelled
Analogue Methods... .......................108
7.2.3.4 Solid Phase Antigen Free Hormone Kit
Methods....................................109
7.2.4 Market Data for Thyroid Function Tests. .......110
7.3 Tumour Markers. ....................................111
7.3.1 Introduction. .................................111
7.3.2 Clinical Utility of Tumour Markers. ...........111
7.3.3 Other Diagnostic Applications of Antibodies
in Oncology....................................112
7.3.4 The Major Tumour Markers. .....................112
CEA ...........................................112
AFP ...........................................112
hCG ...........................................113
Neurone-Specific Enolase (NSE). ...............113
Prostate-Specific Antigen (PSA) ...............113
Tissue Polypeptide Antigen (TPA) ..............113
CA19-9 ........................................114
CA125 .........................................114
CA15-3 ........................................114
7.3.5 Immunoassays for Oncogenic Viruses ............114
7.3.6 Market Data for Cancer-Related Immunoassays. ..115
7.4 Immunoassays in Reproductive Endocrinology. ........116
7.4.1 Introduction. .................................116
7.4.2 Role of Immunoassay Tests. ....................116
7.4.3 Market Data for Reproductive Endocrinology
Immunoassays...................................117
7.5 Immunoassays in Haematology. .......................118
7.5.1 Introduction. .................................118
7.5.2 Market Data for Haematology Immunoassays. .....119
7.6 Immunoassays in the Management of Allergies. .......119
7.6.1 Introduction. .................................119
7.6.2 Market Data on Allergy-Related Immunoassays. ..120
7.7 Immunoassays in Infectious Disease Testing. ........120
7.7.1 Introduction. .................................120
7.7.2 Range and Uses of Available Tests. ............121
7.7.3 Market Data on Infectious Disease
Immunoassays...................................121
7.8 Immunoassays and Drug Monitoring. ..................122
7.8.1 Introduction to TDM. ..........................122
7.8.2 Advantages of TDM. ............................122
7.8.3 Problems Associated with TDM. .................123
7.8.4 Digoxin-Like Immunoreactivity. ................123
7.8.5 Drugs-of-Abuse Screening. .....................124
7.8.6 Market Data for Immunoassay Drug Testing. .....125
7.9 Other Clinical Immunoassays. .......................125
7.10 Non-Medical Immunoassays. .........................126
7.10.1 Introduction. ................................126
7.10.2 Veterinary Immunodiagnostics. ................126
7.10.3 Immunoassays for Plant Diseases. .............127
7.10.4 Immunoassays for Pesticide Residues and
Toxins........................................128
7.11 Summary of the Immunoassay Market in Western
Europe.............................................128
APPENDIX 1: CORPORATE DIRECTORY............................129
|
