Describe how phagocytosis of a bacterium by a dendritic cell leads to the presentation of its antigens.

Describe how the presentation of this bacterial antigen leads to the secretion of antibodies against it.

Cardiac myosin is a structural protein found in human heart valve tissue. Rheumatic heart disease is an autoimmune condition where the body's immune system damages its own heart valves, causing chest pain and breathing difficulties. Scientists have found that the bacterium Streptococcus pyogenes expresses a surface protein called M protein that is structurally very similar to cardiac myosin.

Suggest how an infection by S. pyogenes can result in the development of rheumatic heart disease.