Anti-insulin antibody and insulin antibody

Type 1 and LADA
1

Hi there,

Just curious what is the difference between anti-insulin antibody and insulin antibody...

Anyone has any idea?

Cheers,
Patron

2

Ok, so Insulin AutoAntibodies (IA2) are antibodies that attack your natural (endogenous) insulin production. These are one of the primary antibody markers for T1 diabetes (the others are GAD and ICA). Anti-Insulin Antibodies are antibodies that attack insulin, usually external (exogenous) insulin. Once you start endogenous insulin, within a short amount of time the presence of exogenous insulin will cause IA2 to not be a meaningful diagnostic test for T1. So I guess technically IA2 is a specific form of Anti-Insulin Antibodies.

3

Hi!

They are the same thing. An antibody is a protein produced by your immune system. Basically, we are talking about an antibody that targets insulin.

4

Hi Brian,

Thanks for your reply. But I'm still confused about this sentence. Endogenous insulin means the insulin I produced internally by my pancreas, right? and exogenous means the one from injection? So I'm kind of confused about this sentence here: "Once you start endogenous insulin, within a short amount of time the presence of exogenous insulin will cause IA2 to not be a meaningful diagnostic test for T1. ".

Looking forward to your reply.

Cheers,
Patron

5

Hi FHS,

Thanks for your reply. I can understand that insulin antibody is the protein that detects and destroy insulin, is this right? But what about anti-insulin antibody?

Cheers,
Patron

6

I thought anti-insulin antibodies were related to attaching injected insulin and causing extreme insulin resistance in some Type 1s, and is related to allergies? I did a quick google and found this: http://www.ncbi.nlm.nih.gov/pubmed/19125765, and there are other similar reports.

Then the other type, as Brian mentioned, is one of the autoantibodies associated with Type 1.

Basically one type is related to autoimmunity (mistakenly attacking your own body/cells), the other is related to allergy (mistakenly attacking external substances that are harmless).

Hopefully I'm not just confusing the issue even more. I think the exact differences are all pretty technical and confusing!

7

So, why are IA2 AutoAntibodies identifiable before beginning insulin therapy? Is it because they are different from antibodies that attack exogenous insulin and slowly disappear over time? Or, is it because antibodies to exogenous insulin are indistinguishable from those that attack endogenous insulin?

I can understand having a different designation if they are different proteins or, even, if it's just to distinguish the fact that one type are present before insulin therapy and the other type is present after. Otherwise, the different designations seem a bit redundant.

8

That makes much more sense Jen. There are differences between injected and endogenous insulin which may result in different antibodies being produced against either, or not, but they are all basically attacking insulin, hence, Anti-insulin antibodies.

Antibodies against the cells producing insulin would definitely have different antigens because the targets are completely different, and definitely be distinguishable from those attacking insulin itself. It would make sense to call them Autoantibodies, as in antibodies attacking your own cells.

9

Patron, the way you are phrasing the question, I would again say that there is no substantial difference between an insulin antibody and an anti-insulin antibody. Both designations indicate that they are attacking insulin.

Jen are suggests that there are antibodies that attack the cells in the pancreas actually responsible for producing the insulin. Those are different from Anti-insulin antibodies and are called AutoAntibodies instead.

I'm hoping Brian will clarify what he posted.

10

Ooops, yes that was an error. It should have read "Once you start exogenous insulin, within a short amount of time the presence of exogenous insulin will cause IA2 to not be a meaningful diagnostic test for T1." The external insulin may produce an antibody response and that can totally mask the antibody response to your own insulin that would be measured by IA2.

11

Antibodies are very specific. Antibodies to endogenous insulin are actually different than antibodies to exogenous insulin. They are however very similar. Unfortunately, the measurements for these antibodies is not doesn't have a perfect specificity and the two antibody types can be confused in the test. Heck, I don't even know whether there is a separate IA2 and insulin antibody test. I think they just use the same one. I believe there is a separate test for bovine exogenous insulin antibodies.

12

Hi Patron: I don't know if this will help, but here is a link to one of the best Type 1 autoantibody articles I have found.

13

I think anti insulin antibody is a misnomer. antibody means anti.( goes against)

so Anti-insulin Antibody is really a double negative. Both mean the body's defense against things that do not belong there, and insulin is sometimes attacked as "not self" The body creates antibodies to combat this.

Sometimes the body creates antibodies to natural insulin and different antibodies to injected insulin, Really it does not matter because most T1 diabetic are not making insulin anymore.

Not to be confused with the antibodies that attack the islet cells, Those are totally different antibodies, which mistakenly attack islet cells because they have a similar protein signature as a Virus known to the body as a threat.

I hope that clears it up a little.

14

Thank you everyone. You guys are very helpful. All these discussions cleared my doubt. Thanks again. Cheers.

15

jen is correct...it's a test used to see if one has an allergy or having a reaction to their insulin, which would result in a very high level of insulin resistance.