Immunology & Immunological Disorders Poster Session



Materials & Methods


Discussion & Conclusion



INABIS '98 Home Page Your Session Symposia & Poster Sessions Plenary Sessions Exhibitors' Foyer Personal Itinerary New Search

Activation and Deposition of Human Breast-milk Complement C3 Opsonins on a Serum Sensitive Bacteria

Contact Person: Michael O. Ogundele (mogundel@yahoo.com)


A number of immunological and non-immunological components have been discovered in the human breast-milk that contribute to the observed protective effects of breast-feeding. Little is known however, about the role and contribution of the human breast-milk (HBM) complement (C) system in the protection of both the maternal mammary gland and the nursing infant. The present studies provide evidence that the HBM C is capable of being activated by bacteria, and that the bacteria is subsequently coated with C3 fragments, which would opsonize it and enhance its phagocytosis and killing by milk neutrophils and macrophages.

The serum complement (C) system consist of at least 19 proteins, mostly in pre-activated enzymatic forms, activated in a multi-step cascade reaction via either the classical or alternative pathways. The classical pathway is activated mainly by antigen-antibody complexes (IgG or IgM mostly) starting with C1q (1). The alternativw pathway (APC) utilizes active sites (such as are present on zymosan, yeast, cobra venom, gram-negative bacteria, sheep erythrocytes and human cells deficient in the expression of regulatory molecules) in the presence of properdin, serum factors B and D, to activate C3. The two pathways proceeds uniformly after C3 activation to the formation of (C5b-9) membrane attack complexes (MAC), capable of inserting into biological membranes and producing cell lysis and death (2).

Back to the top.

<= Abstract INTRODUCTION Materials & Methods =>

| Discussion Board | Next Page | Your Poster Session |
Ogundele, M.O.; (1998). Activation and Deposition of Human Breast-milk Complement C3 Opsonins on a Serum Sensitive Bacteria. Presented at INABIS '98 - 5th Internet World Congress on Biomedical Sciences at McMaster University, Canada, Dec 7-16th. Available at URL http://www.mcmaster.ca/inabis98/immunology/ogundele0177/index.html
© 1998 Author(s) Hold Copyright