Duijvestijn A M, Barclay A N
J Leukoc Biol. 1984 Nov;36(5):561-8. doi: 10.1002/jlb.36.5.561.
Ia+ cells of bone marrow origin were studied in the thymus of normal and bone marrow-reconstituted radiation chimeras of rats and characterized on morphology and acid phosphatase (APh)- and Ia-staining pattern in-vivo and in-vitro. In-vivo, the majority of the bone marrow-derived Ia+ cells were present in the medulla. They were large, had cell processes extending between surrounding thymocytes, and frequently weak APh activity. In-vitro, the Ia staining was demonstrated on the cell surface in variable intensity. Ia+ cells showed a frayed outline with cell processes between adherent thymocytes and had weak cytoplasmic APh activity, frequently in a central spot. They had an elongated, usually invaginated, nucleus and a rather pale cytoplasm, in which Birbeck granules sometimes were observed. The characteristics of the bone marrow-derived Ia+ cells demonstrate these cells are an equivalent of the interdigitating cells present in thymus medulla. They distinguish themselves from a population of Ia-, strongly APh+ macrophages predominantly localized in the cortex, and from the Ia+, APh- thymic reticular epithelial cells.
对正常大鼠以及骨髓重建辐射嵌合体大鼠胸腺中骨髓来源的Ia⁺细胞进行了研究，并在体内和体外对其形态、酸性磷酸酶（APh）和Ia染色模式进行了表征。在体内，大多数骨髓来源的Ia⁺细胞存在于髓质中。它们体积较大，有细胞突起延伸至周围的胸腺细胞之间，且酸性磷酸酶活性通常较弱。在体外，Ia染色在细胞表面呈不同强度显示。Ia⁺细胞呈现出参差不齐的轮廓，在贴壁的胸腺细胞之间有细胞突起，且细胞质酸性磷酸酶活性较弱，通常集中在中央点。它们有一个细长的、通常内陷的细胞核和相当淡的细胞质，有时在其中观察到Birbeck颗粒。骨髓来源的Ia⁺细胞的特征表明，这些细胞等同于胸腺髓质中存在的交错突细胞。它们与主要位于皮质的Ia⁻、酸性磷酸酶强阳性的巨噬细胞群体以及Ia⁺、酸性磷酸酶阴性的胸腺网状上皮细胞不同。
