Elola María Teresa, Chiesa María Elena, Fink Nilda Ester
Departamento de Ciencias Biológicas, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, Calle 47 y 115, 1900 La Plata, Argentina.
Comp Biochem Physiol B Biochem Mol Biol. 2005 May;141(1):23-31. doi: 10.1016/j.cbpc.2005.01.004.
Galectins are a family of animal lectins defined by their beta-galactoside-binding activities and a consensus sequence in their carbohydrate-recognizing domain (CRD). Relevant roles of galectins are described in adaptive immune response, innate immunity and modulation of the acute inflammatory response. We have extended our previous studies on a porcine spleen galectin-1 in relation to its functional roles such as polymorphonuclear neutrophils (PMNs) stimulation compared to well known PMN activators e.g. N-formyl-L-methionyl-L leucyl-L-phenylalanine (fMLP) and phorbol 12-myristate 13-acetate (PMA). Relative to activation of NADPH-oxidase fMLP and PMA are stronger than galectin-1 plus cytochalasin B (CB) when the lectin is employed at low concentrations (gal-1 1 microM, 3.6+0.8 nm O(2)(-)/min/10(7) PMN). Higher doses of galectin-1 (10 microM) plus CB produced a significant activation of NADPH-oxidase (27.9+14.8 nm O(2)(-)/min/10(7) PMN) and stimulated PMN degranulation up to 50%. We propose that local galectin-1 concentrations under physiological conditions might reach suitable levels for pig PMN stimulation, and might be a natural inducer of O(2)(-) formation or degranulation. Porcine galectins might produce enhanced responses in vivo when they stimulate neutrophils in combination with some other stimuli.
半乳糖凝集素是一类动物凝集素，其定义基于它们的β-半乳糖苷结合活性以及碳水化合物识别结构域（CRD）中的共有序列。半乳糖凝集素在适应性免疫反应、先天免疫和急性炎症反应的调节中发挥着相关作用。我们扩展了之前关于猪脾脏半乳糖凝集素-1的研究，探讨了其功能作用，例如与已知的多形核中性粒细胞（PMN）激活剂（如N-甲酰-L-甲硫氨酰-L-亮氨酰-L-苯丙氨酸（fMLP）和佛波酯12-肉豆蔻酸酯13-乙酸酯（PMA））相比，对PMN的刺激作用。当低浓度使用凝集素时（半乳糖凝集素-1为1微摩尔，3.6 + 0.8纳米O₂⁻/分钟/10⁷个PMN），相对于NADPH氧化酶的激活，fMLP和PMA比半乳糖凝集素-1加细胞松弛素B（CB）更强。更高剂量的半乳糖凝集素-1（10微摩尔）加CB可显著激活NADPH氧化酶（27.9 + 14.8纳米O₂⁻/分钟/10⁷个PMN），并刺激PMN脱颗粒达50%。我们提出，生理条件下局部半乳糖凝集素-1的浓度可能达到刺激猪PMN的合适水平，并且可能是O₂⁻形成或脱颗粒的天然诱导剂。当猪半乳糖凝集素与其他一些刺激物联合刺激中性粒细胞时，可能在体内产生增强的反应。
