Project Description

Human Cell Line Activation test (h-CLAT)


The OECD 442E h-CLAT assay investigates key event 3 of the skin sensitisation adverse outcome pathway – dendritic cell activation. Utilising the monocytic THP-1 cell line, the ability of a test substance to increase expression of CD54 & CD86 cell surface markers is assessed by flow cytometry. Upregulation of these cell surface markers is associated with dendritic cell activation and leads to the stimulation of an immune response required for sensitisation of the skin to the test substance.

Gentronix have validated their h-CLAT protocols to demonstrate proficiency for the OECD guideline, and now conduct these routinely to GLP.

OECD GuidelineOECD 442E
Adverse Outcome Pathway Key EventNumber 3 – activation of dendritic cells
What it measuresIncrease in expression of cell surface markers (CD86 and CD54) measured by flow cytometry
What is the relevance of that?Activation of dendritic cells is a precursor for the stimulation of T-cell proliferation, leading to skin allergenicity
Cell linehuman monocytic leukaemia cell line THP-1
Incubation time with test item24 hours
Can be conducted to GLP?Yes
ProcedureAt least two independent runs
Protocol performedEURL ECVAM DB-ALM Protocol No 158

h-CLAT OECD 442E Proficiency Data

  Gentronix values consistent with OECD reference rangeGentronix study calls consistent with OECD reference
Test chemicalIn vivo classificationCV75CD86CD54CD86 CallCD54 Callh-CLAT classificationClassification correct
2,4-DinitrochlorobenzeneSensitiser (extreme)PositivePositiveSensitiser
4-PhenylenediamineSensitiser (strong)PositiveNegativeSensitiser
Nickel sulfateSensitiser (moderate)PositivePositiveSensitiser
2-MercaptbenzothiazoleSensitiser (moderate)NegativePositiveSensitiser
R(+)-LimoneneSensitiser (weak) Negative PositiveSensitiser
Imidazolidinyl ureaSensitiser (weak) Positive PositiveSensitiser
IsopropanolNon-sensitiser Negative NegativeNon-sensitiser
GlycerolNon-sensitiser Negative NegativeNon-sensitiser
Lactic acidNon-sensitiser Negative NegativeNon-sensitiser
4-Aminobenzoic acidNon-sensitiser Negative NegativeNon-sensitiser

Predictive Toxicology, Expertly Delivered