Why Are Some Tissues Damaged by Diphtheria Toxin While Others

question 78

Multiple Choice

Why are some tissues damaged by diphtheria toxin while others are unaffected by it?

• A) Diphtheria toxin is a superantigen. Only TH cells are affected by this type of toxin, so tissues lacking TH cells are unaffected.
• B) The causative agent is inhaled into the lungs, so only lung tissue is affected by the toxin released by the organism.
• C) Diphtheria toxin is an A-B toxin. Cells that do not have a receptor for the toxin are unaffected by it.
• D) The causative agent is ingested, so only gastrointestinal tissue is affected by the toxin released by the organism.
• E) Diphtheria is a localized infection. Only tissues in the immediate area of the bacteria are affected by the toxin.

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