The component of the mycobacteria responsible for the adjuvant effect is muramyl dipeptide . The route of administration of a vaccine can affect the antibody isotype the vaccine elicits and its overall efficacy. An oral route of administration results in sIgA production by the MALT, a desirable consequence if the infectious microorganism usually gains access to the body through the mucosa. Passive immunity A. Natural passive immunity 1. IgG passively transferred via the placenta provides the child with antitoxic, antiviral, and some kinds of antibacterial protection during the first six months of life.
Maternal antibodies can also interfere with a child's immune response to an antigen.
For this reason, vaccination against measles is now carried out at 15 months of age instead of 12. Factors that nonspecifically inhibit undesirable flora include lysozyme, lactoferrin, and interferon. Specific immunity is provided by secretory IgA, IgG, and IgM. B. Artificial passive immunity 1. Injecting preformed antibodies can be life-saving in situations where toxins are already circulating in an individual's bloodstream. In addition to these, horse antibodies are frequently used to treat snake bites and scorpion stings.