Share This:
https://ntp.niehs.nih.gov/go/imm96015abs

Abstract for imm-96015

Assessment of Contact Hypersensitivity to Dicyclohexylcarbodiimide in B6C3F1 Female Mice

FULL REPORT PDF

Abstract

Dicyclohexylcarbodiimide (DCC) was selected for evaluation as a sensitizing agent for contact hypersensitivity in mice. DOC is most commonly used in the area of protein synthesis. It has application in the chemical and pharmaceutical industries as well as laboratory usage in the area of recombinant DNA and bioenergetics.

The objective of this study was to determine the sensitizing potential of DOC when applied dermally to female B6C3F1 mice. Measurement of the contact hypersensitivity response was accomplished by the mouse ear swelling test (MEST), and the local lymph node assay (LLNA). Concentrations to be used in the contact hypersensitivity assays were determined by irritancy studies. The doses of DOC tested were .003, .006, .03 and .06% in acetone (99.8%) for sensitization, and .1% for challenge in the MEST and .006, .03, .06 and .1% for sensitization in the LLNA. DNFB (2,4-dinitrofluorobenzene, ICN Pharmaceuticals) was used as the positive control at a concentration of .25% for sensitization, and .5% for challenge.

Dicyclohexylcarbodiimide was identified as a potential contact sensitizer in these studies. The MEST identified DCC as a sensitizer at concentrations as low as .006% at 24 (p<0.05) and 48 (p<0.01) hours post challenge. The LLNA detected a significant response with concentrations as low as .06% DOC (p<0.01). The positive control, DNFB, showed a statistically significant response in both assays.

Studies

Summary of Irritancy and Contact Hypersensitivity Results
Type of Response Method Used Dose Response (p < 0.05) Positive Response (p < 0.05)
Irritation Ear Swelling Yes Yes
.1 MIC, .06 MNC
Contact Hypersensitivity MEST 24 hrs Yes Yes
.006%
MEST 48 hrs Yes Yes
.006%
MEST Pos. Cont NA Yes
LLNA Yes Yes
.06%
LLNA Pos. Cont NA Yes

Abbreviations: Pos. cont. = positive control; LLNA = Local Lymph Node Assay; MEST = Mouse Ear Swelling Test; NA = Not Applicable; MIC= Minimal Irritating Concentration; MNC = Maximal Non-Irritating Concentration.