Project Description
Human Cell Line Activation test (h-CLAT)
SERVICE INFORMATION
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 Guideline | OECD 442E |
| Adverse Outcome Pathway Key Event | Number 3 – activation of dendritic cells |
| What it measures | Increase 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 line | human monocytic leukaemia cell line THP-1 |
| Incubation time with test item | 24 hours |
| Can be conducted to GLP? | Yes |
| Procedure | At least two independent runs |
| Protocol performed | EURL ECVAM DB-ALM Protocol No 158 |
h-CLAT OECD 442E Proficiency Data
| Gentronix values consistent with OECD reference range | Gentronix study calls consistent with OECD reference | |||||||
|---|---|---|---|---|---|---|---|---|
| Test chemical | In vivo classification | CV75 | CD86 | CD54 | CD86 Call | CD54 Call | h-CLAT classification | Classification correct |
| 2,4-Dinitrochlorobenzene | Sensitiser (extreme) | Positive | Positive | Sensitiser | ||||
| 4-Phenylenediamine | Sensitiser (strong) | Positive | Negative | Sensitiser | ||||
| Nickel sulfate | Sensitiser (moderate) | Positive | Positive | Sensitiser | ||||
| 2-Mercaptbenzothiazole | Sensitiser (moderate) | Negative | Positive | Sensitiser | ||||
| R(+)-Limonene | Sensitiser (weak) | Negative | Positive | Sensitiser | ||||
| Imidazolidinyl urea | Sensitiser (weak) | Positive | Positive | Sensitiser | ||||
| Isopropanol | Non-sensitiser | Negative | Negative | Non-sensitiser | ||||
| Glycerol | Non-sensitiser | Negative | Negative | Non-sensitiser | ||||
| Lactic acid | Non-sensitiser | Negative | Negative | Non-sensitiser | ||||
| 4-Aminobenzoic acid | Non-sensitiser | Negative | Negative | Non-sensitiser | ||||
