Assays to "prove" I have Type 1 Beta Cell loss (i.e. I'm a regular Type 1)

Reply

Short-Jan replied on Mon, Jun 1 2009 10:26 PM

rated by 0 users

Have you recently had a thyroid function test? I had unexplained and very rapid lows caused by a low thyroid. Perhaps that's part of the problem.

Jan

Reply

tomjef replied on Mon, Jun 1 2009 11:44 PM

rated by 0 users

Brice,

You would probably be interested in the research being done at Joslin by George King, M.D., their director of research. Joslin has records on all the type 1s who have received 50-year medals, and Dr. King, along with his research associate, Hillary Keenan, Ph.D., have been studying the 50-year medalists who are still living. After much testing of medalists, they have found that there are a few medalists who are still making a little bit of their own insulin, and that may be where you are headed! The implications of this research may be quite significant if a way can be found to get those remaining beta cells to avoid destruction by the immune system. They would be your own beta cells, so they would not require suppression of the immune system.

Tom Beatson

Reply

Spirit replied on Tue, Jun 2 2009 9:39 AM

rated by 0 users

Brice:  Unfortunately, I have no answers to your questions.  However, they sound like good ones.  You may not get the information you need until you set up the questions correctly.

I am T2, so I have no background experience in T1.  However, I know that stress will consistently raise my bg.  If you were under chronic stress do you think that it is possible that this artifically inflated your glucose levels?  So that, as the stress diminished the glucose rise did as well?  If that were the case, then your treatment would be aimed at a target that no longer exists.  Does this makes sense within the physiological parameters of T1?

The onset of T1 coinciding with trauma, either psychological or physical, is typical, is it not? 

I sincerely hope that you can find the answers to your questions and unravel this mystery. 

Spirit

Reply

bricedue replied on Tue, Jun 2 2009 10:55 AM

rated by 0 users

tomjef, THANK YOU!!

This was exactly the kind of info I was hoping to get here... eventually. And you delivered so quickly!

I am going to email King and Keenan later today. They will certainly know what assays to do to rule out or confirm residual beta-cells in my body. That will be awesome.

Your avatar makes me think you might be in (or close to) the 50 year survivors group. Congrats! That's my goal too: a long long life free of complications. It must feel good to be there -- and to still be here.

Thanks again and I will post their answers to my questions later this week.

-brice

P.S. as far as native beta cell therapies, I think we will see CGM+pump "artificial" beta cells much much sooner. The Freestyle Navigator is pretty close to perfect for the job already, and the current gen of pumps are so close to faultless that little remains to be improved. The really tricky part is closing the feedback loop with 100% reliability -- not 99.9999%, because that will not be good enough. It needs to be pacemaker reliable. That level of reliability will probably take another 10+ years to get FDA approval. No company will ever want the CGM to command a bolus from the pump erroneously...

Reply

zrebiec replied on Tue, Jun 2 2009 12:07 PM

rated by 0 users

300 years ago it was thought that diabetes was the result of "prolonged sadness." More recent research implies that stress may (a) directly affect blood glucose levels and (b) indirectly affect blood glucose levels by changes in behavior. It is also well-accepted that personal interpretation of blood glucose results might create stress. In addition, it appears from anecdotal experience that psychological stress might be one factor providing the "final blow" to the onset of diabetes, but is in itself, not a cause of diabetes.

John Zrebiec, MSW, CDE

Moderator

Reply

tomjef replied on Tue, Jun 2 2009 6:03 PM

rated by 0 users

Brice,

You expressed the opinion "The Freestyle Navigator is pretty close to perfect". I've been using a Navigator for 10 months and have been pleased with how it has improved my control, beyond the pump. But I disagree that it is pretty close to perfect. I have always bolused before meals, and there have been quite a few times when the Navigator will start giving me alarms for low BG just as I sit down to eat, and throughout the time when I am eating, taking in the carbs it's suggesting that I need. On the other hand, it's wonderful to be able to go for a 20-mile bicycle ride with the Navigator receiver mounted on the handlebar so by pushing one button I can see my glucose level right now. Of course that's the glucose level in the interstitial fluid, not the blood, and there is a difference. Like so many other things with diabetes, perfection is seldom possible.

Tom Beatson

Reply

bricedue replied on Tue, Jun 2 2009 9:45 PM

rated by 0 users

... You are right Tom. I should have been more careful with my language.

I was gushing about the potential of the technology (I'm a geek) not about the maturity of the tech.

My Navigator is showing up tomorrow... :)

The 5-day 1440x per day measurements are what is needed for a successful "artificial" beta cell.  The reliability is going to have to improve. The delay between capillary blood levels and interstitial is probably worse than the delay between veinous BG and capillary BG measured by current-gen meters like the Precision (my curtrent favorite). And the 10 hour startup period will have to go away! :(

I imagine that for a real CGM+pump solution there will need to be a semi-permanent "port" into a vein somewhere. Improvements in infection control will be needed. You probably know that the 5-day limit for Navigator Sensors is nothing to do with the sensors failing... it's FDA concerns over site infection that limits each sensor to 5 days per site.

The sensor tech itself seems to be much more robust that the current implant system. They have tethered "live" glucose oxidase (?) enzymes to a tiny wire fillament. The wire captures the electrons liberated by the oxidation of glucose molecules, and the meter measures the charge/voltage/capacitance produced over time. The enzymes are not used up in the process. And they are native human isoforms so the immune system ignores the "foreign" bodies for a long time. It would be interesting to know the max implant time during trials...

 (Caveat: the above explanation of the tech is contains a lot of reading between the lines, and is based on what I know of Abbott's patented techs, and based on the name they've assigned to the Navigator sensor tech: "Tethered Enzyme." I haven't yet dug up the Navigator patent apps to read them...)

-brice

P.S. Wow, serious cycling without eating handfulls of raisins every 10 mins... sound great!

Reply

tomjef replied on Tue, Jun 2 2009 11:21 PM

rated by 0 users

Brice,

Since you are just starting the Navigator, you are allowed to gush! I'm sure you will like it.

I have been using each Nav sensor for 10 days usually, and occasionally for 15. There is a specific technique that must be used to restart the sensor when it reaches the 5-day limit, and unfortunately you have to go through another 10-hour startup. I have found that much of the 10-hour period can be sleep time. Don't ask Abbott for the restart technique! I don't think the FDA will let them talk about such things.

Instead of resorting to handsful of raisins while riding the bicycle, I have been using a temp basal rate (determined by much experimenting) that allows me to go for 10-15 miles, and there's always a restaurant at the end of those 10-15 miles. I get the bonus of a second breakfast before I return home on the second half of my ride. Experimenting to find the right temp basal kind of came naturally to me as an EE and computer engineer. The second breakfast gets a bolus at 1/30, compared to 1/12 for the first breakfast. The Navigator on my bike allows me to eat a glucose tablet if necessary.

Tom Beatson

Reply

Ron AKA replied on Tue, Jun 2 2009 11:56 PM

rated by 0 users

bricedue:

MY QUESTION: what assays can be done at Joslin Boston to "prove" I am a conventional Type 1? I mean things like quantitative proinsulin and insulin/c-peptide, along with autoantibodies or other markers for Beta-cell presence/absence and/or T-cell activation/absence? What would be a sufficient panel to definitively say I have lost all Beta-cell function? What would be a sufficient panel to prove I retain residual Beta-cells even after 16 years?

I would think the C-Peptide would go a long way to show what beta cell function remains. The GAD test would also help but is not 100% conclusive from what I know about it.

Reply

bricedue replied on Wed, Jun 3 2009 12:03 AM

rated by 0 users

Hi Tom, I emailed you directly about the "restart" technique. I'm too tired to google around to see if it's already public somewhere.

As for raisins: raisins are my friends. I don't have a pump, so tweaking my basal isn't an option. I have always told myself I'll get a pump once they marry it to a CGM. (I was dreaming about the inevitability of CGMs before the buzzwords left the marketer's mouths.) I'm happy with needles, buuuut... I'm pretty sure I'll begin to crave finer control once I get used to having so much data imersion with the Navigator.

What do you like about your Deltec Cozmo over the others out there?

-brice