Recombinant S100 Proteins

R&D Systems continues to add to its industry-leading selection of S100 family proteins. This includes the only commercially available S100 A8/A9 heterodimers in the industry.

S100 proteins are exclusively found in vertebrates, and 21 members have been identified in Human. S100s are low molecular weight (9-13 kDa) proteins with two calcium-binding EF-hand motifs. They are typically dimers (homo and hetero), and can also exist as oligomers depending on the presence of divalent metal ions.

Despite sequence and structure similarities, S100s are not functionally interchangeable, and they participate in many important biological processes such as proliferation, differentiation, inflammation and migration/invasion. Dysregulated S100 proteins are associated with neurological disorders (such as Down syndrome and Alzheimer’s), psoriasis, and many cancers.

S100 Family Bioactivity. A. Recombinant Human S100A8/S100A9 (Catalog # 8226-S8) induces IL-6 secretion by A375 human melanoma cells. The ED50 for this effect is 1.5-6 µg/mL. IL-6 was measured using the Human IL-6 Quantikine® Kit (Catalog # D6050). B. Recombinant Mouse S100A9 (Catalog # 2065-S9) induces CXCL1/KC secretion in C3H10T1/2 mouse embryonic fibroblast cells. The ED50 for this effect is 0.036-0.18 µg/mL. CXCL1/KC was measured using the Mouse CXCL1/KC Quantikine® ELISA Kit (Catalog # MKC00B). C. Recombinant Human S100B (Catalog # 1820-SB) induces human peripheral blood monocyte proliferation. The ED50 for this effect is 1-4 µg/mL. proliferation was measured using the redox-sensitive dye Resazurin (Catalog # AR002)

S100A4-induction of Neurite Outgrowth. Recombinant Human S100A4 (Catalog # 4137-S4) enhances neurite outgrowth of dissociated E13 chick embryonic dorsal root ganglia (DRG) neurons.