InScotland, they found that they got more true positive Western Blots when they used local strains of Borrelia. Which is exactly what Igenex does when they test against 2 strains instead of only 1 used by most testers.
The use of local isolates in Western blots improves serological diagnosis of Lyme disease in Scotland.
Nine Scottish Borrelia burgdorferi isolates were investigated in IgG Western blot tests. Sera previously found to be positive and negative when tested by routine Western blots prepared from reference strain B. burgdorferi sensu stricto antigen had different outcomes with these isolates. Two isolates, E5 (Borrelia afzelii) and G4 (B. burgdorferi sensu stricto) performed well, reproducing Western blot-positive results in 90 and 95 % of tests, respectively. When antigens from both isolates were incorporated into a single IgG Western blot, the results of a panel of sera were improved when compared to the routine reference strain IgG Western blot. All of the sera positive by the routine Western blot remained positive using the Scottish isolate antigen mix. Twenty-three of the 25 negative sera remained negative and two produced an equivocal result. Of the 15 samples that tested IgG Western blot equivocal with the B. burgdorferi sensu stricto reference strain, 11 (73 %) became weak or strong positive when tested with the B. afzelii/B. burgdorferi sensu stricto antigen mix (chi(2)=14.35, Yates' correction, P<0.001). In seven of these, a clinical picture of Lyme disease was consistent with the new results. The use of Scottish strains of B. afzelii and B. burgdorferi sensu stricto to provide antigen for the IgG Western blot improves the diagnosis of Lyme disease for patients in Scotland.
PMID: 17172516 [PubMed - in process]
Posted by Truthfinder (Member # 8512) on :
I did not know this about Igenex - what strains do they use?
Tracy
Posted by Truthfinder (Member # 8512) on :
Oh, I just saw this. I've got to check it out more later, so I'll bump it up so I will see it tomorrow.
Thanks, Cave!
Tracy
Posted by shazdancer (Member # 1436) on :
Ooh, thanks for finding the corroboration on the Igenex site, cave. You know how it is when someone says, "I never heard that," and then you think, am I sure I heard that?
Anyway, this is my understanding (just conjecture) on what "all the Lyme antigens more or less equally represented" means.
I am assuming that different strains of Borrelia burgdorferi, as well as different species of Borrelia (such as B. afzelii, B. garinii, B. japonica, et al) express themselves differently on the Western Blot. Perhaps one strain reacts strongly on band 34, while another reacts weakly, and perhaps another doesn't show up at all.
If I were Igenex, I would be trying to find the lowest number of Bb strains that would have the highest combined number of strongly reactive bands. As in, Strain A reacts strongly on 1, 2, 4, and 6, so combine it with Strain B that reacts on 2, 3, 5, and 7, so you cover as many bands as you can. Apparently they have achieved this by using strains 31 and 297. They now have enough strongly reactive antigens to also be sensitive to other bacteria in the Borrelia genus, so patients from other countries may also test positive on the Igenex Western Blot.
That's my take on it, anyway.
Posted by Truthfinder (Member # 8512) on :
Not sure exactly what they mean by that statement either, Cave. Shaz made a good guess.
If I understand this correctly, I think it is fascinating that the Igenex test picks up other sub-strains (or species - the terminology gets confusing depending on what you read) of Borrelia other than just Bb.
When I wrote to Igenex last January, the reply I got said ``our tests are specific for Borrelia burgdorferi (95%)''.
Apparently, they either made changes in the test, or figured out that their Western Blots were already picking up species/ sub-strains other than just Bb.
When they refer to: ``The IGX Western Blots have been evaluated and have reactivity against....``the sub-strains of B. burgdorferi from Colorado, Missouri and Texas''
do you suppose they are referring to these Borrelia critters? Borrelia bissettii (Colorado, etc., formerly sensu lato group DN127) ``Masters Disease'' (Missouri) Lonestari (Texas)
And if so, why don't they just SAY that?
Tracy
Posted by Truthfinder (Member # 8512) on :
I'm sure you are right, Joe - that the test itself can't reveal specific information about strains and sub-strains. In fact, I'm surprised and pleased that they did their homework and tried to determine WHAT strains/ sub-strains their WBs were picking up. I have to give them points for that.
I have a feeling that they don't publish the actual names of the sub-strains because they don't want a zillion phone calls of people asking how they can determine which sub-strain they have.
Hmmm. Maybe Joe should be the one to call Igenex. He understands the various strains better than most, and besides - what else has he got to do, what with snipe season being over and all?
Tracy
Posted by Truthfinder (Member # 8512) on :
Joe,
See, I KNEW you were the right guy for this job. You've already talked with Nick Harris. Heck, I've never even had a WB, so what do I know?
When they refer to ``the sub-strains of B. burgdorferi from Colorado, Missouri and Texas'', I would hardly call those ``offshore'' genotypes or strains.
So, maybe Old Nick has some new information, and he might be willing to share a few more specifics with someone knowledgeable like yourself.
Wow. The way New Mexico treats Lyme is a lot like the old Project Blue Book, with just about the same level of credibility.
I think Colorado stays a ``non-endemic'' state because the ducks here just don't offer to test anybody. You have to ask to be tested for Lyme. And they just use whatever lab they've contracted with - some use Quest, some use LabCorp.
Do you have any idea what strains Quest and LabCorp use for their WB strips? I certainly don't. In fact, I didn't have a clue about how WBs were done until I read this thread.
In this state, we are only concerned about Colorado Tick Fever, Rocky Mountain Spotted Fever, and Relapsing Fever. If you want to know anything about other TBDs, the State Disease Control and Epidemiology Division website shuffles you off to the CDC website. How helpful.
The only reason I know that Lyme is a problem in my own county is from talking to my veterinarian who does test for Lyme, and finds it in dogs that have never been out of the area. But my vet doesn't know squat about stuff like Babesia. Well, don't think the ducks here to either.
Off Topic:
Regarding future contests, RULE #1 has GOT to be: NO CHEATING! This means that Cave can't go back and edit her post after she sees me give the right answers. Any editing of a post means an automatic disqualification. NO EXCEPTIONS.
You might want to rethink the low-cut apron, corset, bustier ideas. It's like spandex: some people just shouldn't go there.
Tracy
Posted by Truthfinder (Member # 8512) on :
I don't know how I missed seeing this answer before today.... it's a darn wonder I ever caught you cheating in the first place.
Tracy
Posted by bettyg (Member # 6147) on :
shaz, could you break up your 1st post in solid text? i'd sure like to read it concerning igenex, etc.
i recd. 100 of their western blot igm/igg brochures yesterday that i give out to those with symptoms of lyme. thanks shaz! Posted by Karenelee (Member # 11044) on :
Does anybody know what strains Quest and Lab Corp use? I heard that one of them uses a German strain.
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