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Detection of human contact sensitivity to dinitrochlorobenzene by the migration inhibiton test
Abstract:
The migration inhibitory factor (MIF) production of peripheral lymphocytes following exposure to dinitrophenylated microsomes derived from both human (DNP-hy-Mic) and guinea pig (DNP-gp-Mic) epidermis was quantitated to detect human contact sensitivity to dinitrochlorobenzene (DNCB). The lymphocytes from nonsensitized subjects did not generate MIF following exposure to either antigen. With DNP-gp-Mic as the antigen, MIF production was noted in only 1 out of 6 DNCB-sensitized subjects and was not significant statistically. With DNP-hu-Mic as the antigen, highly significant MIF production was observed in all 12 sensitized subjects ( p less than 0.0005). In order to confirm MIf production by sensitized lymphocytes following stimulation by DNP-hu-Mic, the subjects were actively sensitized with DNCB and MIF production was assessed before and after sensitization. Remarkable MIf production was noted in the lymphocyte cultures after sensitization, although no significant MIF production was observed before sensitization. MIF production of the sensitized lymphocytes cultured in the presense of DNP-hu-Mic generally correlated well with the results of patch testing, but not with the intensity of the skin test.
Insights
Human contact sensitivity to dinitrochlorobenzene (DNCB) can be detected by measuring migration inhibitory factor (MIF) production. Peripheral lymphocytes from DNCB-sensitized individuals produced significant MIF when exposed to human DNP-microsomes, confirming a reliable diagnostic marker.
Area of Science:
- Immunology
- Dermatology
- Contact Hypersensitivity
Background:
- Contact sensitivity to dinitrochlorobenzene (DNCB) is a common delayed-type hypersensitivity reaction.
- Assessing DNCB sensitivity often relies on patch testing, which can have limitations.
- Migration inhibitory factor (MIF) is a cytokine involved in immune responses, including delayed-type hypersensitivity.
Purpose of the Study:
- To evaluate the utility of migration inhibitory factor (MIF) production by peripheral lymphocytes as a diagnostic marker for human contact sensitivity to dinitrochlorobenzene (DNCB).
- To compare the efficacy of human (DNP-hy-Mic) versus guinea pig (DNP-gp-Mic) derived dinitrophenylated microsomes in eliciting MIF production in DNCB-sensitized individuals.
Main Methods:
- Quantitation of MIF production from peripheral lymphocytes after in vitro exposure to DNP-hy-Mic and DNP-gp-Mic.
- Assessment of MIF production before and after active sensitization with DNCB.
- Correlation of MIF production with patch test results in DNCB-sensitized subjects.
Main Results:
- Lymphocytes from non-sensitized subjects did not produce MIF upon antigen exposure.
- DNP-gp-Mic elicited significant MIF production in only 1 out of 6 DNCB-sensitized subjects.
- DNP-hy-Mic induced highly significant MIF production in all 12 DNCB-sensitized subjects (p < 0.0005).
- MIF production increased remarkably after active DNCB sensitization, with minimal production observed prior to sensitization.
- MIF production correlated well with patch test results but not with skin test intensity.
Conclusions:
- In vitro migration inhibitory factor (MIF) production by peripheral lymphocytes stimulated with human dinitrophenylated microsomes (DNP-hy-Mic) is a sensitive and specific indicator of dinitrochlorobenzene (DNCB) contact sensitivity.
- This MIF assay offers a potentially valuable diagnostic tool for assessing DNCB-induced contact hypersensitivity, complementing traditional patch testing.