Immunological maturation, the gradual increase in affinity for antigen of serum antibody with time after immunization, has been postulated to result from a competition among precursors of antibody-forming cells for available antigen (1, 2). Thus, as the antigen concentration in the cellular environment falls, only those cells with antigen-binding receptors of sufficiently high avidity to captur...

Grand ChallenGes The question of self–non-self discrimination, and thereby immunological tolerance, is as old as our appreciation of the receptor-diversity in the immune system. Initially negative selection of self-reactive lymphocytes by clonal deletion in primary lymphoid organs, enhanced by promiscuous expression of ectopic antigens in these organs, attracted attention. It became clear, howe...

Ali Azizi ; Catalina Soare ; Thanh Le ; Danylo Sirskyj ; Andrei Ogrel ; David Anderson ; Jose Torres ; Richard Weltzin ; Francisco DiazMitoma 1,2,3 1-Variation Biotechnologies Inc; 2-Department of Pathology and Laboratory Medicine, University of Ottawa; 3-Children's Hospital of Eastern Ontario Research Institute; 4-Department of Medical Microbiology and Immunology, University of California Davi...

A B S T R A C T Cell-mediated and humoral immilune responses of mutant diabetic db+/db+ mice were evaluated using in vivo and in vitro immunological assays. When compared to lean, nondiabetic db+/m+ or m+/m+ mice, db+/db+ mice demonstrated markedly altered in vivo immune responses characterized by a significantly diminished ability to reject allogeneic skin grafts, a markedly diminished capacit...

Introduction: Some strains of Escherichia Coli, including intestinal pathogenic strains, commensal strains, and extra intestinal pathogenic E. coli (ExPEC) have a significant impact on human health status. A standard vaccine designed based on conserved epitopes can stimulate a protective immune response against these pathogens. Additionally, enhanced expression at the infection site as a pathog...

IMMUNOLOGICAL METHODS. Edited by J. F. Ackroyd. Oxford, Blackwell Scientific Publ. Co. (in U.S.A., distributed by F. A. Davis Co., Philadelphia), 1964. xvi, 628 pp. $16.00. This volume records the proceedings of a symposium organized by the Council for International Organizations of Medical Sciences (CIOMS). Although no details of time or place are given, I have been told that the meeting was h...

Although most mouse strain combinations succumb to a lethal wasting disease when parabiosed across a strong histocompatibility (H-2) barrier, a high proportion of DBA mice parabiosed to DBA/C3H F(1) hybrids survive and appear healthy. DBA mice accept C3H skin grafts following parabiosis, and may therefore be considered operationally tolerant of C3H antigens. Nonetheless, spleen cells from long-...