AAMC #7 and H.Pylori problem

[Jay2910]

---

Members don't see this ad.

Hello everyone,

I have a quick question regarding question #130 on the Biological Sciences section of Test #7.

Basically its asking why the host antibodies are ineffective against H.Pylori.

So basically I'm given that H.Pylori can create gastic cancer, ulcers and knows how to evade the immune system.

I don't understand why the answer is (A) . . .they say that the antibodies will denature in stomache environment.

I always thought that if the antibodies were to be released . ..they would be releasing though the blood stream. Stomach acid, is controlled via certain cells and glands within the stomach walls( right?)
What does the blood stream have in connection with stomach acid?

 

[Barley426]

Helicobacter pylori colonizes the lumen of the stomach (where the food is) so in order to be effective, the antibodies would need to be released into the stomach. Antibodies are regularly secreted into the gastrointestinal tract, (typically IgA isotope) If this were to happen in the stomach (it doesn't) the antibodies would denature and be ineffective anyway. An antibody in the blood specific to H. Pylori would be useless unless there was some bacteria in the blood, which would be bacteremia (which leads to sepsis) and would still not affect the H. pylori in the stomach.

 

[Jay2910]

Yes! I totally get it now! Thank you so much! Where did you get an explanation like that? TBR?

 

[Barley426]

Lol, that was all out of my noggin.

I liked microbiology a little too much me thinks.

 

[MedPR]

Hello everyone,

I have a quick question regarding question #130 on the Biological Sciences section of Test #7.

Basically its asking why the host antibodies are ineffective against H.Pylori.

So basically I'm given that H.Pylori can create gastic cancer, ulcers and knows how to evade the immune system.

I don't understand why the answer is (A) . . .they say that the antibodies will denature in stomache environment.

I always thought that if the antibodies were to be released . ..they would be releasing though the blood stream. Stomach acid, is controlled via certain cells and glands within the stomach walls( right?)
What does the blood stream have in connection with stomach acid?

This question can be answered in a couple of different ways, both of which you guys already mentioned.

1. Antibodies are proteins. Proteins denature in low pH (like in the stomach).
2. Antibodies are in the blood stream, not in the stomach lumen.