p-phenylenediamine

Immunotoxicity

Administrative data

Endpoint:

immunotoxicity: acute dermal

Type of information:

experimental study

Adequacy of study:

supporting study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Scientific method followed conventional research techniques, though no guideline was cited. Good documentation.

Data source

Reference

Reference Type:

publication

Title:

Unnamed

Year:

1993

Materials and methods

Principles of method if other than guideline:

Lymphocyte proliferation test method

GLP compliance:

not specified

Limit test:

no

Test material

Test material information

Constituent 1

Details on test material:

- Purity: Not reported

Test animals

Species:

other: human

Sex:

not specified

Administration / exposure

Route of administration:

dermal

Vehicle:

petrolatum

Duration of treatment / exposure:

72 hours

Frequency of treatment:

single exposure

Doses / concentrations

Remarks:

Doses / Concentrations:
1% (patch test), 0.25 to 10 µg/mL (Lymphoproliferative Assays) and 1 µg/mL (Generation of Antigen-Specific T Cell Lines)
Basis:

No. of animals per sex per dose:

16 Patients

Control animals:

yes

Results and discussion

Effect levels

Dose descriptor:

other: immunotoxicity

Basis for effect level:

other: The test substance is the allergenic, but not the immunogenic agent, in test substance contact sensitivity.  N, N'-bis(4-aminophenyl)-2,5-diamine-1,4-quinone-diimine may be the immunogenic haptan.

Remarks on result:

not measured/tested

Remarks:

Effect level not specified (migrated information)

Any other information on results incl. tables

The test substance is the allergenic, but not the immunogenic agent, in test substance contact sensitivity.  N, N'-bis(4-aminophenyl)-2,5-diamine-1,4-quinone-diimine may be the immunogenic haptan. Optimal stimulation was observed at a concentration of 2 µg/mL. Lymphocyte stimulation was high for 2 patients within the test group. The results of the PBMC PPD-Allergic test show that from the 3 haptens related to the phenylendiamines that were tested in this study, BB is the best indicator of test substance sensitivity in vitro.

 

Hapten-specific T cell lines were generated from PBMC of test substance-allergic patients in the presence of the test substance and BB. Although the test substance-specific T cell line exhibited some proliferative response to the test substance (10E3 at 1 µg/mL), the higher proliferative rate obtained using BB indicated that this cell line was more specific to BB than to the test substance. On the other hand, the BB-specific T cell line did not respond at all to the test substance but strongly proliferated to BB. These data suggest that, in these experiments, the 'test substance-specific' T cells are in fact reactive to BB.

Applicant's summary and conclusion

Conclusions:

The test substance is the allergenic, but not the immunogenic agent.

Executive summary:

A lymphoproliferative assay was performed on human volunteers. The test substance was applied to the upper back for 72 hours. The proliferative response was response was assessed. The test substance is the allergenic, but not the immunogenic agent, in test substance contact sensitivity.  N, N'-bis(4-aminophenyl)-2,5-diamine-1,4-quinone-diimine may be the immunogenic haptan. Optimal stimulation was observed at a concentration of 2 µg/mL. Lymphocyte stimulation was high for 2 patients within the test group. The results of the PBMC PPD-Allergic test show that from the 3 haptens related to the phenylendiamines that were tested in this study, BB is the best indicator of test substance sensitivity in vitro.

 

Hapten-specific T cell lines were generated from PBMC of test substance-allergic patients in the presence of the test substance and BB. Although the test substance-specific T cell line exhibited some proliferative response to the test substance (10E3 at 1 µg/mL), the higher proliferative rate obtained using BB indicated that this cell line was more specific to BB than to the test substance. On the other hand, the BB-specific T cell line did not respond at all to the test substance but strongly proliferated to BB. These data suggest that, in these experiments, the 'test substance-specific' T cells are in fact reactive to BB.