The Agglutination of Staphylococcus aureus in the Presence of Normal or Influenza Virus-infected Mouse Lung Filtrates and of Chorio-allantoic Fluids *

The agglutination of bacteria by substances other than those associated with specific an;tigen-antibody reactions is a well-recognized phenomenon. Certain physical and chemical properties of the medium in which organisms grow or may be suspended often influence the degree of dispersion of the cells. An illustration of this is seen in "acid agglutination." In fact, the critical level of the hydrogen ion concentration at which a given species of bacteria will agglutinate may be quite characteristic for that species. Further, some variant forms of bacteria are frequently readily agglutinated by the addition of electrolytes. It has been pointed out' that surface tension of media influences the growth characteristics of some bacteria and agglutination will occur if the surface tension reaches 45 dynes or less. This is particularly true in the case of the typhoid and paratyphoid organisms. Just where the agglutination of bacteria growing in normal or virus-infected lung filtrates and in egg fluids fits' into this scheme of agglutination is problematical, since the mechanism involved is not known. The observations of Penner and Voldrich7 on the agglutination of staphylococci by tuberculous effusions possibly correspond to the reactions to be described below more closely than anything else found in the literature. However, these workers suggest that their results were due to antigen-antibody reactions. Such an explanation is questionable in the present case involving the egg fluids, but may be applicable to the observations in the lung-filtrate experiments. The present paper is an extension and detailed analysis of results presented in a preliminary report9 concerning the agglutination of