Diagnostic Kit for Human Tuberculosis Using the Combined ELISA & IFNγ Release Assay (An Innovative Solution for TB Control) Current epidemiological status of TB · TB re-emerged as a major global health threat · 1/3 of the world's population infected with Mycobaterium tuberculosis MTB · Around 9 million people develop the disease per year · An estimated 2-3 million people die of TB each year Latent TB infections (LTBI) · The majority of TB infections are latent TB · It may reactivate later in life · Tuberculin skin test (TST) was once the only means of diagnosing LTBI · TST problem is lack of specificity due to cross-reactivity with BCG and other Mycobacterium. Innovative Solution · The Immune-based blood test, Interferon-Gamma Release Assays (IGRA), has dramatically improved the diagnosis of LTBI. www.biopanda.co.uk Presentation of mycobacterium antigens Memory T Cell Antigen Specific T Cell produces IFNγ APC Principal of IGRA 1990 1995 2000 2005 2010 Global trends in case notification (black) & estimated TB incidence (green) rates, 1990–2010 1 150 100 50 0 Rate per 100 000 population 1 WHO report 2011 – Global TB control p40 Method Advantage Disadvantage IGRA • Not affected by BCG & other Mycobacteria • Higher specificity to LTBI & TB • Accurate indicator for LTBI & a better predictor for the development of TB • Fast result, less bias & can be repeated • Freshly-collected whole blood required • Basic laboratory & technical skills are required • High cost TST • A standard Test • Simple • Cheaper • Affected by BCG & other mycobacteria • Revisit doctor for results • Higher bias in interpretation of result • Testing can’t be repeated Comparison between TST and IGRA IFN γ Responsible Diagnostic Solutions

Diagnostic Kit for Human Tuberculosis Using the Combined ... · 1 · TB re-emerged as a major global health threat · 1/3 of the world's population infected with Mycobaterium tuberculosis

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Diagnostic Kit for Human Tuberculosis Using

the Combined ELISA & IFNγ Release Assay (An Innovative Solution for TB Control)

Current epidemiological status of TB

· TB re-emerged as a major global health threat · 1/3 of the world's population infected with Mycobaterium tuberculosis MTB · Around 9 million people develop the disease per year · An estimated 2-3 million people die of TB each year

Latent TB infections (LTBI)

· The majority of TB infections are latent TB · It may reactivate later in life · Tuberculin skin test (TST) was once the only means of diagnosing LTBI · TST problem is lack of specificity due to cross-reactivity

with BCG and other Mycobacterium.

Innovative Solution

· The Immune-based blood test, Interferon-Gamma Release Assays (IGRA), has dramatically improved the

diagnosis of LTBI.

www.biopanda.co.uk

Presentation of mycobacterium antigens

Memory T Cell

Antigen Specific T Cell produces IFNγ

APC

Principal of IGRA

1990 1995 2000 2005 2010

Global trends in case notification (black) & estimated TB incidence (green) rates, 1990–20101

150 100 50 0

Rat

e p

er 1

0 p

ula

tio

1 WHO report 2011 – Global TB control p40

Method Advantage Disadvantage

IGRA • Not affected by BCG & other Mycobacteria

• Higher specificity to LTBI & TB • Accurate indicator for LTBI & a

better predictor for the development of TB

• Fast result, less bias & can be repeated

• Freshly-collected whole blood required

• Basic laboratory & technical skills are required

• High cost

TST • A standard Test • Simple • Cheaper

• Affected by BCG & other mycobacteria

• Revisit doctor for results • Higher bias in

interpretation of result • Testing can’t be

repeated

Comparison between TST and IGRA

IFN γ

Responsible Diagnostic Solutions

Page 2: Diagnostic Kit for Human Tuberculosis Using the Combined ... · 1 · TB re-emerged as a major global health threat · 1/3 of the world's population infected with Mycobaterium tuberculosis

Analytical sensitivity

Specimen Measurement range

Package Shelf life

0.15625 IU/ml Freshly-collected

Whole blood 0.15625 IU/ml

to 10 IU/ml 96 wells

(for 27 samples) 12 months

Unit 14, Carrowreagh Business Park Carrowreagh Road Belfast, BT16 1QQ United Kingdom Tel : +44 (0)28 95438774 E-mail: [email protected] Website: www.biopanda.co.uk

Whole blood sample collected

Overview of the IFNγ Assay Technology The TB-ELiFN kit is based on the combination of IGRA technology and

enzyme-linked immunosorbent assay (ELISA) test systems, to measure the interferon gamma (IFNγ) released by memory T cells in human whole blood through in-vitro stimulation with specific MTB antigens.

Sensitised T cells release IFNγ

Incubation in 3 tubes provided (16-20 hours at 37oC)

IFNγ production measured using TB-ELiFN

Results read using an ELISA plate reader

Results expressed as IU/ml

TB-ELiFN Features

Specific antigens employed in the kit are identified only in MTB; not in BCG strains or most non-tuberculous mycobacteria

No cross-reactivity is found with other cytokines, e.g. IL-2 (40 ng/ml), IL-4 (5 ng/ml), IL-5, IL-6, IL-8, IL-10, IL12 (100 ng/ml)

No separation of T cells is required Sensitivity at 94.23% is reached with active TB patients

A high throughput ELISA test system Specificity at 96.23% is reached with healthy volunteers

Standard provided in liquid form Stability: at least 12 months

Plasma specimen collected and assay performed