Antibody Formation in Volunteers Following Injection of Pneumococci or Their Type-Specific Polysaccharides Pneumococcal Infections Polysaccharides Antibodies During World War II, Heidelberger became involved in an effort by military physicians to develop a pneumonia vaccine, consisting of a combination of purified polysaccharides of four specific pneumococcal types, for the immunization of troops. In this article, Heidelberger and one of his wartime collaborators, Colin MacLeod, along with two coauthors described improvements in their quantitative precipitin method for measuring the amount of type-specific anti-pneumococcal antibodies in human sera, measurements that revealed that an even smaller amount of the specific polysaccharide than used previously was sufficient for effective immunization. Additionally, the team provided data on various injection methods (subcutaneous vs. intracutaneous) and the duration of protection (antibody levels remained relatively constant for 5-8 months after injection). Rockefeller Institute for Medical Research, March 1946 Rockefeller Institute for Medical Research, March 1946 Journal of Experimental Medicine Heidelberger, Michael MacLeod, Colin M. MacLeod, Colin M. Kaiser, Samuel J. Robinson, Betty Articles Archival Materials Text 18 pages nlm:nlmuid-101584940X33-doc 101584940X33 http://resource.nlm.nih.gov/101584940X33 Profiles ID: DHBBCP English Profiles in Science