Dendritic cell assay

Immunomodulation not only relates to a series of physiologic and pathologic phenomena, but also it can be estimated by related reaction cells, such as mast cells, DCs and NK cells, and level of cell factors such as interleukin, interferon, tumor necrosis factor, and transforming growth factor. Based on those facts, the rat mast cell and rabbit aortic assay [105], dendritic cell assay [106], lymphoid organ assay [107], IFN-y assay [108], anti-rHuEPO NAb assay [109], and chemotaxic assay [110] are established. 

This test uses an in vitro human dendritic cell culture to obtain information of the potential for various chemicals to induce allergic contact dermatitis. This test is used as an alternative to the Local Lymph node assay (LLNA) to minimize or replace the use of live animal testing for predicting skin sensitization (Kimber et al. 2002, see below). The test allows for evaluation of skin sensitization by examining the presence of cell surface markers on Periperal Blood Mononuclear Cell (PBMC)-derived dendritic cells (DC) that are known to be involved in the development of allergic contact dermatitis. 

Aiba S, Terunuma A, Manome H, Tagami H (1997) Dendritic cells differently respond to haptens and irritants by their production of cytokines and expressin of co-stimulatory molecules. Eur J Immunol 27 3031-3038 Hulette B, Gilmour N, Ryan C et al. (2003) Relationship of CD86 surface marker expression and cytotoxicity on dendritic cells exposed to chemical allergens. Toxicol 72 54 Kimber I, Dearman RJ, Basketter DA et al. (2002) The local lymph node assay past, present and future. Contact Dermatitis 47 315-328... 

B-cell receptor bovine semm albumin cerium (IV) ammonium nitrate complement dependent cytotoxicity CDS cytotoxic T-lymphocytes l,8-diazabicyclo[5.4.0]undec-7-ene dendritic cell deoxyribonucleic acid epidermal growth factor enzyme-linked immunosorbent assay endoplasmic reticulum ethyl... 

Ayehunie, S., Snell, M., Child, M., Klausner, M. (2009) A plasma-cytoid dendritic cell (CD123+/CDllc-) based assay system to predict contact allergenicity of chemicals. Toxicology, 264 (1-2), 1-9. 

The cellular targets of MDC, with respect to chemotaxis, include monocyte-derived dendritic cells, IL-2-activated NK cells (maximal effect observed at 1 ng/mL MDC for both cell types), and activated T lymphocytes. It is important to note that whereas the former observations (responses of DC and NK cells) involved use of human cells in microchemotaxis assays (40), the latter observation was based on the ability of STCP-1 to stimulate transendothelial migration of activated murine T lymphocytes (41). In microchemotaxis assays, peripheral blood monocytes also appear to respond, but this effect requires significantly greater amounts of MDC (maximal effect at 100 ng/mL) than those for chemotaxis of DCs and NK cells. Whereas STCP-1 stimulated transendothelial migration of activated T cells, neutrophils, eosinophils, and peripheral blood monocytes failed to respond. 

Thus, the relationship of coreceptor function to structure is inherently complex. However, interpretation of structure-function studies are further complicated by the necessity to take account of methodological variables. For example, assays for which the read-out is cell-fusion rather than measures of viral replication are probably insensitive to any postentry processes involving the coreceptor. Yet, such processes may be central to the failure of some HIV and SIV strains to replicate efficiently in certain cell types, including macrophages and dendritic cells (36-39). 

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