Nichols B A
J Exp Med. 1976 Oct 1;144(4):920-32. doi: 10.1084/jem.144.4.920.
In this investigation, vacuoles containing tubular myelin proved to be digestive compartments with cytochemical reactivity for acid phosphatase and arylsulfatase. These cytochemical markers identify the secondary lysosomes, known to contain enzymes capable of hydrolyzing phospholipids like surfactant. Therefore, it appears that alveolar macrophages possess the enzymatic machinery for the degradation of the tubular myelin found in their digestive vacuoles. Although it thus appears evident that alveolar macrophages participate in the turnover of surfactant, the quantitative significance of this route of disposal is undetermined. This investigation has also established that acid hydrolases, so prominently displayed in the secondary lysosomes, are also localized in the rough endoplasmic reticulum and in Golgi-endoplasmic reticulum-lysosomes (GERL). Moreover, small vesicles which are produced from GERL serve as primary lysosomes in transporting digestive enzymes to the vacuoles.
在本研究中，含有管状髓磷脂的液泡被证明是具有酸性磷酸酶和芳基硫酸酯酶细胞化学反应性的消化区室。这些细胞化学标志物可识别次级溶酶体，已知其含有能够水解如表面活性剂等磷脂的酶。因此，肺泡巨噬细胞似乎拥有降解其消化液泡中管状髓磷脂的酶机制。虽然肺泡巨噬细胞参与表面活性剂周转这一点似乎很明显，但这条处置途径的定量意义尚不确定。本研究还证实，在次级溶酶体中显著显示的酸性水解酶也定位于粗面内质网和高尔基体内质网溶酶体（GERL）。此外，由GERL产生的小泡作为初级溶酶体，将消化酶运输到液泡中。
