title: Isolation and assay of a human plasma factor affecting human thymus-derived lymphocytes.
abstract: An amino acid-containing factor has been isolated from a dialysate of defibrinated human plasma using Sephadex G-25 and Sephadex CM-25 column chromatography. This factor is capable of enhancing "avid" E-rosette formation by normal human lymphocytes, where avid E-rosettes are defined as lymphocytes binding 10 or more sheep red cells. This factor is effective at concentrations as low as 10(-12) g/ml. It resembles the porcine and murine "facteur thymique sérique" (e.g. J.-F. Bach, M. Dardenne, J.-M. Pleau, and J. Rosa, Nature (London) 266, 55, 1977) in its elution characteristics, its capacity to enhance avid E-rosette formation and, tentatively, its amino acid composition.
mesh_terms: D000818:Animals; D004306:Dose-Response Relationship, Immunologic; D006801:Humans; D008214:Lymphocytes / Q000378:metabolism; D051379:Mice; D012397:Rosette Formation; D013552:Swine; D013935:Thymic Factor, Circulating / Q000302:isolation & purification / Q000502:physiology*; D013951:Thymus Hormones / Q000502:physiology*
chemical_list: D013951:Thymus Hormones; D013935:Thymic Factor, Circulating