Question is as follows:
In cell #1, the addition of bivalent anti-insulin receptor antibodies induces a response without the addition of insulin. In cell #2, addition of a fragment anti-receptor antibody (monovalent) induces no response without insulin. To cell #2, antibodies against the monovalent anti-receptor antibodies are added. This will result in:
A. no response
B. decreased glucose uptake
C. increased CO2 production
D. increased insulin binding.
Explanation: The question tells us that the addition of bivalent anti-insulin receptor antibodies induces a response without insulin. The bivalent structure will induce cross-linking, leading to a clustering of insulin receptors. This conclusion is bolstered by the next sentence of the question which states that monovalent antibodies, which cannot produce cross-linking, do not induce a response in the absence of insulin. However, if we add antibodies against these monovalent antibodies/fragments, we should be able to induce cross-linking and thus clustering. Therefore, we should be able to induce an insulin-like response, which involves the promotion of glucose as a fuel. When glucose is oxidized, the carbons are released as carbon dioxide.
Ok so I am a little confused about the whole monovalent fragments and bivalent fragments and in general cross-linking in association with antibodies. Can someone explain the question and the explanation differently or make it more clear, I am still a little confused about the insulin receptor clustering; can't seem to picture it in my head. This question is from TBR Biology book 1 section 5 on immunology, page 316. Thanks and any help is much appreciated!
In cell #1, the addition of bivalent anti-insulin receptor antibodies induces a response without the addition of insulin. In cell #2, addition of a fragment anti-receptor antibody (monovalent) induces no response without insulin. To cell #2, antibodies against the monovalent anti-receptor antibodies are added. This will result in:
A. no response
B. decreased glucose uptake
C. increased CO2 production
D. increased insulin binding.
Explanation: The question tells us that the addition of bivalent anti-insulin receptor antibodies induces a response without insulin. The bivalent structure will induce cross-linking, leading to a clustering of insulin receptors. This conclusion is bolstered by the next sentence of the question which states that monovalent antibodies, which cannot produce cross-linking, do not induce a response in the absence of insulin. However, if we add antibodies against these monovalent antibodies/fragments, we should be able to induce cross-linking and thus clustering. Therefore, we should be able to induce an insulin-like response, which involves the promotion of glucose as a fuel. When glucose is oxidized, the carbons are released as carbon dioxide.
Ok so I am a little confused about the whole monovalent fragments and bivalent fragments and in general cross-linking in association with antibodies. Can someone explain the question and the explanation differently or make it more clear, I am still a little confused about the insulin receptor clustering; can't seem to picture it in my head. This question is from TBR Biology book 1 section 5 on immunology, page 316. Thanks and any help is much appreciated!