After a bout of strep throat, a child develops acute rheumatic fever. Which mechanism explains this autoimmune response in the heart valves?

💡 Explanation

Acute rheumatic fever arises due to molecular mimicry, where antibodies against Streptococcus bacteria cross-react with heart valve tissue because the bacterial antigens resemble self-antigens. Therefore, the immune system attacks the heart valves rather than only the bacteria because of this similarity, rather than other immune dysfunctions.

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