You are here:
A COMPARISON OF CYTOKINE MESSAGE AND PROTEIN PROFILES OBTAINED FOLLOWING DERMAL EXPOSURE TO DIISOCYANATES.
Citation:
BOYKIN, E., M. J. DANIELS, D. L. ANDREWS, AND M. K. SELGRADE. A COMPARISON OF CYTOKINE MESSAGE AND PROTEIN PROFILES OBTAINED FOLLOWING DERMAL EXPOSURE TO DIISOCYANATES. Presented at 45th Annual Society of Toxicology Meeting 2006, San Diego, CA, March 06 - 09, 2006.
Description:
Exposure to certain low molecular weight chemicals is associated with asthma. A simple method to identify this hazard is needed. Increased expression of Th2 cytokine mRNA in draining lymph nodes following dermal exposure and increased production of Th2 cytokines by cultured cells from these lymph nodes have been pursued as possible screening tests, usually with chemicals of known sensitizing potential. Previously, we developed cytokine mRNA profiles using the RNAse protection assay for 6 diisocyanates (some well-documented sensitizers and others less documented), 1% toluene diisocyanate (TDI), 2% diphenylmethane-4,4-diisocyanate (MDI), 2%dicyclohexylmethane-4,4diisocyanate (HMDI), 2% isophorone diisocyanate (IDPI), 1% P-tolyl (mono) isocyanate (TMI), 1% meta-tetramethylene xylene diisocyanate (TMXDI), and for 1% dinitrochlorobenzene (DNCB, not a respiratory sensitizer). The isocyanates could be divided into high & low responders based on Th2 cytokines. Here we compare cytokine profiles obtained for these same chemicals using different methods. Lymph nodes cells from treated animals were cultured with and without concanavalin A (ConA). Supernatants from ConA treated and untreated cells were collected 24 and120 h, respectively, after culture. Both ELISA and Luminex were used to assay supernatants for cytokines. Message in lymph node and cultured cells was assessed using RT-PCR. For all methods tested the isocyanates fell into 2 groups similar to those identified using RNAse protectionTh2 cytokines. As with the RNase protection assay, we were unable to make distinctions between the diisocyanates and DNCB based on Th1 cytokines. Monocyte chemoattractant protein-1 (MCP-1), a cytokine associated with diisocyanate asthma was most prominently expressed in cells from HMDI, IDPI, TMXDI, and DNCB treated mice. In summary, regardless of method used diisocynates fell into 2 groups based onTh2 cytokine profiles. Th1 and MCP-1 did not yield useful distinctions. (This abstract does not reflect EPA policy).