What type of antigens induce immune response from pathogenic organisms?

The correct answer is microbial antigens, as these are specific components derived from pathogens, such as bacteria, viruses, fungi, and parasites, that are recognized by the immune system. When these antigens are detected, they trigger an immune response intended to neutralize or eliminate the invading pathogens. Microbial antigens can include proteins, polysaccharides, and other molecules present on the surfaces of these organisms. This response is crucial for the body's defense mechanisms, as it allows for the identification and targeting of harmful agents.

In contrast, molecular antigens refer more broadly to any molecules that can elicit an immune response, which may include both microbial and non-microbial sources. Self-antigens are components of the body’s own tissues; while they can play a role in immune tolerance, they do not typically stimulate an immune response. Autoantigens are specific self-antigens that can lead to autoimmune diseases when the immune system mistakenly targets them as foreign. These do not induce immune responses from pathogenic organisms as microbial antigens do.