Module 9 2021

22/03/2021

Cell-based neutralization assay - example

Principle: Reporter gene assay (RGA) Cell line expressing the Firefly luciferase (FL) under a promoter responsive to TNF a

TNF  expression of FL (A) TNF + TNF antagonist  reduced expression of FL (B) TNF + TNF antagonist + neutralising ADA  expression of FL (C)

A

B

C

RLU (FL)

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Cell-based neutralisation assays

Advantages • Functional assay, which distinguishes antibodies with neutralising potential • Provides information on cross-reactivity with other similar preparations Disadvantages • Generally time-consuming • Prone to non-specific matrix effects and interference with inhibitory molecules e.g., soluble receptors • Sensitivity can be an issue • Optimisation and validation are difficult UT7- Epo 200000 250000 E1 E3

150000

cpm

100000

50000

0

10

100

1000

10000 100000

Reciprocal dilution

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