Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, Georgia 30332, USA.
J Biomed Mater Res A. 2010 Mar 15;92(4):1329-42. doi: 10.1002/jbm.a.32457.
Conserved protein-carbohydrate-lipid pathogen-associated molecular patterns (PAMPs) interact with cells of the innate immune system to mediate antigen recognition and internalization and activation of immune cells. We examined if analogous "biomaterial-associated molecular patterns" composed of proteins, specifically their carbohydrate modifications, existed on biomaterials, which can play a role in mediating the innate immune response to biomaterials. To probe for these carbohydrates in the adsorbed protein layer, as directed by the underlying biomaterial chemistry, self-assembled monolayers (SAMs) presenting -CH(3), -OH, -COOH, or -NH(2) were preincubated with serum/plasma, and the presence of carbohydrate ligands of C-type lectin receptors (CLRs) was investigated using lectin probes in an enzyme-linked lectin assay (ELLA). Presentation of CLR ligands was detected on control tissue culture polystyrene (TCPS). Absorbances of mannose or N-acetylglucosamine increased with decreasing incubating serum concentration, whereas absorbances of sialylated epitopes or fucose remained unchanged. Absorbances of alpha-galactose or N-acetylgalactosamine decreased with decreasing incubating serum concentration; beta-galactose was undetectable. Among SAM endgroups, preincubation with 10% serum resulted in differential presentation of CLR ligands: higher alpha-galactose on COOH SAMs than NH(2) or CH(3) SAMs, highest complex mannose on NH(2) SAMs, and higher complex mannose on OH SAMs than CH(3) SAMs. Least sialylated groups were detected on CH(3) SAMs. In summary, biomaterial chemistry may regulate protein adsorption and hence unique presentation of associated carbohydrates. The ultimate goal is to identify the effects of protein glycosylations associated with biomaterials in stimulating innate immune responses.
保守的蛋白-碳水化合物-脂类病原体相关分子模式 (PAMPs) 与先天免疫系统的细胞相互作用,介导抗原识别和内吞作用以及免疫细胞的激活。我们研究了类似的“生物材料相关分子模式”是否存在于生物材料中,这些模式由蛋白质组成,特别是它们的碳水化合物修饰,它们可以在介导对生物材料的先天免疫反应中发挥作用。为了探测吸附蛋白层中的这些碳水化合物,根据基础生物材料化学的指导,预先孵育呈现 -CH(3)、-OH、-COOH 或 -NH(2)的自组装单层 (SAM),并用凝集素探针在酶联凝集素测定 (ELLA) 中研究 C 型凝集素受体 (CLR) 的碳水化合物配体的存在。在对照组织培养聚苯乙烯 (TCPS) 上检测到 CLR 配体的呈现。随着孵育血清浓度的降低,甘露糖或 N-乙酰葡萄糖胺的吸光度增加,而唾液酸化表位或岩藻糖的吸光度保持不变。随着孵育血清浓度的降低,alpha-半乳糖或 N-乙酰半乳糖胺的吸光度降低;beta-半乳糖不可检测。在 SAM 末端基团中,用 10%血清预孵育导致 CLR 配体的差异呈现:COOH SAM 上的 alpha-半乳糖高于 NH(2)或 CH(3) SAM,NH(2) SAM 上的复杂甘露糖最高,OH SAM 上的复杂甘露糖高于 CH(3) SAM。在 CH(3) SAM 上检测到最少的唾液酸化基团。总之,生物材料化学可能调节蛋白质吸附,从而独特地呈现相关的碳水化合物。最终目标是确定与生物材料相关的蛋白质糖基化在刺激先天免疫反应中的作用。