A comparison of ultrastructural characteristics of bronchoalveolar macrophages in perfused parenchyma with those obtained by a fixative or physiological saline lavage.

A comparison was made of the ultrastructural characteristics of bronchoalveolar macrophages from perfused lung parenchyma with those obtained from lavage procedures using either a balanced salt solution or buffered fixative. In comparing morphology by scanning and transmission electron microscopy, it was observed that the macrophages recovered through the fixative lavage procedure were more nearly like those found in perfused parenchyma. These characteristics included polarized surface extensions and pleomorphic forms. The cells collected via balanced salt lavage were consistently oval in shape and had randomly distributed peripheral processes. The ultrastructural features were found to be superior in the fixative lavage preparation when compared with those cells obtained in balanced salt solution.