Fliegert F G, Tschernig T, Pabst R
Functional and Applied Anatomy, Medical School of Hannover, Germany.
Exp Lung Res. 1996 Nov-Dec;22(6):677-90. doi: 10.3109/01902149609070037.
Investigations on leukocyte populations in the lung have shown that lymphocytes are found in different anatomical compartments. Lymphocytes can be seen to a different extent in the lung interstitium, the epithelium and lamina propria of the bronchi, the bronchoalveolar space, and the marginal lung vascular bed. Previous studies focused on one compartment only, or a mixture of leukocytes from lung homogenates were prepared. This study compared cellular yields from the lung parenchyma, the bronchoalveolar space, and the perfusate of the lung vasculature of healthy male Lewis rats. All compartments were investigated in the same animal, and seven different lymphocyte subsets, monocytes, and natural killer (NK) cells were analyzed using flow cytometry. It was found that the perfusate contained a high proportion of CD4+ lymphocytes compared to the lung interstitium. A very high proportion of CD4+ lymphocytes in the bronchoalveolar lavage (BAL) expressed markers for "memory" T cells. Compared to the blood, the percentage of B and T cells was much lower in the perfusate, whereas the NK cells and monocytes were more frequent. Analysis of leukocyte subsets within all compartments revealed specific, distinguishable cell compositions. Extraction of interstitial lung cells was performed using two different methods. Enzymatic digestion of the lung tissue was compared with a mechanical disruption method. Hardly any differences were observed between the two methods regarding the distribution of lymphocyte subsets, monocytes, and NK cells. These data document the need to study more than one compartment before extrapolating to lymphocytes in the lung in general. Furthermore, changes in numbers of leukocytes and subsets can now be studied in models of lung infections and immune reactions, including the entry from the blood and intrapulmonary migration from one lung compartment to the other.
对肺部白细胞群体的研究表明，淋巴细胞存在于不同的解剖区域。在肺间质、支气管上皮和固有层、支气管肺泡腔以及肺边缘血管床中都能不同程度地看到淋巴细胞。以往的研究仅聚焦于一个区域，或者制备的是来自肺匀浆的混合白细胞。本研究比较了健康雄性刘易斯大鼠肺实质、支气管肺泡腔和肺血管灌洗液中的细胞产量。在同一只动物中对所有区域进行了研究，并使用流式细胞术分析了七种不同的淋巴细胞亚群、单核细胞和自然杀伤（NK）细胞。结果发现，与肺间质相比，灌洗液中CD4 +淋巴细胞的比例较高。支气管肺泡灌洗（BAL）液中很高比例的CD4 +淋巴细胞表达“记忆”T细胞标志物。与血液相比，灌洗液中B细胞和T细胞的百分比要低得多，而NK细胞和单核细胞则更为常见。对所有区域内白细胞亚群的分析揭示了特定的、可区分的细胞组成。使用两种不同方法进行肺间质细胞的提取。将肺组织的酶消化法与机械破碎法进行了比较。在淋巴细胞亚群、单核细胞和NK细胞的分布方面，两种方法几乎没有观察到差异。这些数据表明，在对肺部淋巴细胞进行总体推断之前，需要研究多个区域。此外，现在可以在肺部感染和免疫反应模型中研究白细胞及其亚群数量的变化，包括从血液进入以及在肺内从一个区域迁移到另一个区域的情况。
