| Factor |
Function |
| Humoral |
| Secretory IgA |
Immune exclusion, bactericidal activity, ,virus neutralization and prevention of bacterial adherence to epithelial cells [32]. |
| sIgA Mannose glycans |
Inhibit the binding of Type1 fimbriated Escherichia coli to epithelial cells [30]. |
| sIgA Fucose glycans |
Inhibit the binding of Enteropathogenic Escherichia coli to epithelial cells [30]. |
| sIgA Fucose glycans |
Inhibit the binding of Helicobacter pylori to epithelial cells [30]. |
| sIgA Sialicacid-containing glycans |
Inhibit the binding of S-fimbriated Escherichia coli to epithelial cells [30]. |
| sIgA undefined glycans |
Inhibit the binding of Toxin A of Clostridium difficile to epithelial cells [30]. |
| IgM |
Protection of infant against bacterial and viral infections [5]. |
| IgG |
Protection of infant against allergic sensitization [19]. |
| IgE |
Protection of infant against allergic sensitization [19]. |
| IgD |
Inhibition of IgE-induced histamine release but not cytokine production by basophils [26]. |
| Complement Constituents |
Bactericidal activity and protecting both the mammary gland and nursing infant against various pathogens [29]. |
| Cellular |
| Macrophages |
Active phagocytosis of microbes recognised to be “non self” or pathogenic [32]. |
| Lymphocytes and subsets |
Phagocytosis of microbes recognised to be pathogenic [32]. |
| Polymorphonuclear Leucocytes |
Phagocytosis of microbes recognised to be pathogenic [32]. |
| Enzymes |
| Lysozyme |
Attack and lysis to bacterial cell walls [32]. |
| Lactoperoxidase |
Anti-streptococcal activity [32]. |
| Proteins |
| Lactoferrin |
Inhibited Enterotoxigenic Escherichia coli induced hemagglutination of human erythrocytes in vitro [32]. |
| Lactadherin |
Inhibits the replication of rotaviruses [32]. |
| Erythropoietin |
Effects on the integrity of infant’s gut epithelia [5]. |
| Mucin |
Inhibit the binding of pathogenic bacteria and viruses to buccal epithelial cells [30].
Hypothesised to strengthen mucosae against injury caused by specific parasitic infections [30]. |
| Other molecules |
| Transforming Growth Factor (TGF-β) |
Mediate anti-inflammatory responses [5]. |
| Interleukin-1 and Interleukin-8 |
Resistance to certain digestive processes [27] |
| Nerve Growth Factor, Insulin-like Growth Factor, Tumor Necrosis Factor (TNF-α) and Fibroblast Growth Factor |
Hypothesised non-specific anti-parasitic protection [31].
Enhances mucosal barriers and decreases incidence of some neonatal diseases such as necrotising enterocolitis [29,31,33]. |
