Macrophage scavenger receptor as a new macrophage marker

巨噬细胞清道夫受体（Macrophage scavenger receptor， MSR）是巨噬细胞的主要受体之一，在动脉粥样硬化和宿主防御机制中起重要作用。用重组人I型MSR蛋白作为免疫原免疫MSR缺陷小鼠，制备单克隆抗体。Western blot分析证实5种抗体对MSR具有特异性。免疫组化结果显示，所有抗体均能识别组织巨噬细胞，如肺泡巨噬细胞、肝脏库普弗细胞、脾脏红髓巨噬细胞、淋巴结窦巨噬细胞、各器官间质巨噬细胞等。脑血管周围巨噬细胞（Mato细胞）对这些抗体也呈阳性。新鲜分离的血单核细胞阴性；然而，在培养1天后，这些抗体呈阳性。培养3 ~ 5 d时，反应强度随细胞向巨噬细胞分化而增强。淋巴组织树突状细胞如间指细胞和表皮朗格汉斯细胞均为阴性。在早期动脉粥样硬化病变中，这些抗体可识别动脉粥样硬化核心周围的分散巨噬细胞和泡沫巨噬细胞。在各种炎症条件下，这些抗体识别浸润的巨噬细胞。结核和结节病上皮样肉芽肿的上皮样细胞和多核巨细胞也呈阳性。每种抗体对动物都表现出独特的反应模式。特别是，一种名为SRA-E5的抗体可以识别猴子、牛、马、猪、小猎犬、猫、兔子、豚鼠、仓鼠、大鼠和小鼠等多种动物的MSR分子。从这些观察结果来看，这些抗体不仅可用于研究MSRs的作用，而且可用于分析人类和动物巨噬细胞的分化。通过在第7届人类白细胞分化抗原研讨会和会议上对这些抗体的评估，MSR被指定为新的CD分子CD204。少

Macrophage scavenger receptor (MSR) is one of the major receptors of macrophages and play important roles in atherogenesis and host defense mechanisms. Monoclonal antibodies were generated by immunizing MSR-deficient mice with a recombinant protein of human type I MSR as immunogen. Five antibodies were confirmed to be specific for MSR by Western blot analysis.Immunohistochemically, all antibodies recognized tissue macrophages such as alveolar macrophages, Kupffer cells in the liver, red pulp macrophages in the spleen, sinus macrophages in lymph nodes, and interstitial macrophages in various organs. Perivascular macrophages in the brain (Mato cells) were also positive for these antibodies. Freshly isolated blood monocytes were negative ; however, they became positive for these antibodies after 1 day in culture. At 3 to 5 days in culture the reaction intensity became stronger along their differentiation towards macrophages. Dendritic cells such as interdigitating cells of lymphoid tissue … More s and epidermal Langerhans cells were invariably negative. In early atherosclerotic lesions, these antibodies recognized scattered macrophages in intima and foamy macrophages in the periphery of atheromatous cores. In various inflammatory conditions, these antibodies recognized infiltrated macrophages. Epithelioid cells and multinucleated giant cells in epithelioid granuloma of tuberculosis and sarcoidosis were also positive. Each antibody showed a unique reaction pattern against animal species. Especially, an antibody named SRA-E5 recognized MSR molecules of various animal species including monkeys, cows, horses, swine, beagles, cats, rabbits, guinea pigs, hamsters, rats, and mice. From these observations, these antibodies are considered to be useful not only for studying the role of MSRs but also for analyzing macrophage differentiation in human and animals. Through the evaluation of these antibodies at the 7th Workshop and Conference on Human Leucocyte Differentiation Antigens MSR has been assigned to be a new CD molecule, CD204. Less