de Miranda-Santos I K, Bunn-Moreno M M, Campos-Neto A
Departamento de Imunologia, Faculdade de Medicina de Ribeirão Preto da Universidade de São Paulo, Brazil.
J Immunol Methods. 1991 Jul 5;140(2):197-203. doi: 10.1016/0022-1759(91)90371-l.
The biological activities previously described for a crude extract derived from seeds of Artocarpus integrifolia (jack fruit) are shown in the present work to be assigned to two distinct fractions present in this extract. One fraction is the D-galactose binding lectin, jacalin, obtained by affinity purification on a D-galactose Sepharose column. The other fraction is a D-mannose-binding protein which we propose to call 'Artocarpin'. As is well documented, jacalin binds to human IgA1 and is a useful tool for the purification of this immunoglobulin. We show here that the remaining biological activities consisting of the proliferative response of mouse spleen cells and human peripheral blood mononuclear cells and polyclonal activation of human and mouse B cells for the secretion of immunoglobulin are mediated by artocarpin. Artocarpin is unique in its capacity to induce polyclonal activation of B cells in the absence of proliferation. BALB/c nu/nu spleen cells failed to proliferate which indicates that this lectin is a T cell-dependent B cell polyclonal activator.
本研究表明，此前描述的波罗蜜（木菠萝）种子粗提物的生物活性可归因于该提取物中存在的两个不同组分。一个组分是通过在D-半乳糖琼脂糖柱上亲和纯化获得的D-半乳糖结合凝集素——木菠萝凝集素。另一个组分是一种D-甘露糖结合蛋白，我们提议将其称为“波罗蜜素”。正如充分记录的那样，木菠萝凝集素与人IgA1结合，是纯化这种免疫球蛋白的有用工具。我们在此表明，由小鼠脾细胞和人外周血单个核细胞的增殖反应以及人和小鼠B细胞分泌免疫球蛋白的多克隆激活组成的其余生物活性是由波罗蜜素介导的。波罗蜜素的独特之处在于其在不发生增殖的情况下诱导B细胞多克隆激活的能力。BALB/c裸鼠脾细胞未能增殖，这表明这种凝集素是一种T细胞依赖性B细胞多克隆激活剂。
