Ackerman S J, Kephart G M, Habermann T M, Greipp P R, Gleich G J
J Exp Med. 1983 Sep 1;158(3):946-61. doi: 10.1084/jem.158.3.946.
In experiments using an immunofluorescent method to localize human eosinophil granule major basic protein (MBP) in cells and tissues, a small number of cells stained for MBP that subsequently could not be identified as eosinophils. Because the Charcot-Leyden crystal protein, another eosinophil protein, was recently identified in basophils, we tested whether MBP might also be a constituent of blood basophils. Highly purified, eosinophil-free basophil suspensions were prepared using the fluorescence-activated cell sorter (FACS) to sort basophil-containing mononuclear cell preparations stained with fluorescein-conjugated sheep IgG anti-human IgE antibody. Using these FACS-purified basophils, we found that: (a) enrichment for surface IgE-positive cells (greater than 95% basophils) by FACS also enriched for cells staining for MBP by immunofluorescence; (b) MBP appeared to be localized in the histamine-, heparin-containing granules; (c) significant quantities of MBP were measurable by radioimmunoassay (RIA) in freeze-thaw detergent extracts of purified basophils; and (d) RIA dose-response curves for extracts of purified eosinophils and basophils had identical slopes. The MBP content of basophils from normal individuals averaged 140 ng/10(6) cells, whereas purified eosinophils from normal donors and patients with the hyper-eosinophilic syndrome averaged 4,979 and 824 ng/10(6) cells, respectively. MBP was also detected by immunofluorescence and RIA in cells obtained from a patient with basophil leukemia, although the MBP content for basophil leukemia cells was lower than that for normal basophils. We conclude that basophils contain a protein that is immunochemically indistinguishable from eosinophil granule MBP.
在运用免疫荧光法对细胞和组织中的人嗜酸性粒细胞颗粒主要碱性蛋白（MBP）进行定位的实验中，有少量细胞被染成MBP阳性，但随后无法鉴定为嗜酸性粒细胞。由于嗜酸性粒细胞的另一种蛋白——夏科-莱登结晶蛋白最近在嗜碱性粒细胞中被发现，我们测试了MBP是否也可能是血液嗜碱性粒细胞的一种成分。使用荧光激活细胞分选仪（FACS）对用异硫氰酸荧光素偶联的羊IgG抗人IgE抗体染色的含嗜碱性粒细胞的单核细胞制剂进行分选，制备了高度纯化、不含嗜酸性粒细胞的嗜碱性粒细胞悬液。利用这些经FACS纯化的嗜碱性粒细胞，我们发现：（a）通过FACS富集表面IgE阳性细胞（嗜碱性粒细胞比例大于95%）时，也富集了免疫荧光法染成MBP阳性的细胞；（b）MBP似乎定位于含组胺、肝素的颗粒中；（c）通过放射免疫测定法（RIA）可在纯化嗜碱性粒细胞的冻融去污剂提取物中检测到大量的MBP；（d）纯化嗜酸性粒细胞和嗜碱性粒细胞提取物的RIA剂量反应曲线斜率相同。正常个体嗜碱性粒细胞的MBP含量平均为140 ng/10⁶个细胞，而正常供体和高嗜酸性粒细胞综合征患者的纯化嗜酸性粒细胞平均分别为4979 ng/10⁶个细胞和824 ng/10⁶个细胞。在一名嗜碱性粒细胞白血病患者的细胞中，通过免疫荧光和RIA也检测到了MBP，尽管嗜碱性粒细胞白血病细胞的MBP含量低于正常嗜碱性粒细胞。我们得出结论，嗜碱性粒细胞含有一种在免疫化学上与嗜酸性粒细胞颗粒MBP无法区分的蛋白。
