FLUORESCENT-STAINABLE ANTIBODIES TO THE EATON AGENT IN HUMAN PRIMARY ATYPICAL PNEUMONIA TRANSMISSION STUDIES*

Abstract

Preserved sera from 70 volunteers participating in 2 primary atypical pneumonia transmission experiments were examined for fluorescent-stainable antibodies to the Eaton agent. Fluorescent-stainable antibody responses were associated with cases of primary atypical pneumonia and through a spectrum of disease ranging down to apparent subclinical infection. In contrast, rises of cold hemagglutinins and Streptococcus MG agglutinins were limited for the most part to patients with atypical pneumonia and were influenced by the severity of the disease. The explanation of fluorescent-stainable antibody responses in those who had no illness or had minor respiratory illness is not clear; they may represent unapparent or mild infection with the Eaton agent, or they may reflect nonspecific factors as yet unknown. It is concluded that the data presented indicate as association of the Eaton agent with disease in the volunteers studied, although the identity of the agent transmitted could not be determined directly. These results cannot be interpreted as proof of the etiological role of the Eaton agent in primary pneumonia until the exact specificity of the reaction between the agent and fluorescent -stainable antibodies has been established.