Please say it ain't so...

[Steph_in_TX]

My husband called me from work and said there is a story out that Tyler has tested positive twice for a blood transfusion. Read on...

http://www.cyclingnews.com/news.php?...p04/sep21news3

[MightyMitre]

Yep - it's true.

After British rider David Millar tested positve for EPO just before the Tour it was pretty depressing but this is gutting.

Tyler is so cool- I'm pretty p'd off by the news.

Now, I belong to the cynical camp that believes doping in cycling is endemic. I don't believe there are any truely 'clean' pro's. By that I mean any that only use the type of products you and me might use in our day to day training.

Modern demands placed on riders mean if you want to be in with a chance you have to be assisted and in some cases, just to ensure you can keep up with everyone else, let alone win a major race. But it's always depressing when someone you admire gets caught out.

It's depressing that anyone needs to dope in the first place, but what annoys me the most is that while those who get caught obviously have to suffer the penalties,there's still plenty of others getting away with it!

I guess Tyler stands to loose his Olympic medal, sponsorship and even his position at Phonak.

Bahhh - sometime life sucks.

[Veronica]

Liz where are you getting your news from? Velonews says that they they are running more counter tests today, but I'm work so haven't been able to read the latest updates.

What I've read says he's denying it. He's such a classy guy I'd expect him to be up front if he had been caught - like Miller. Of course he could disappoint me.

V.

[MightyMitre]

Ah yes - a bit hasty there.

I was feeling very frustarted and annoyed when I did my earlier post.

According to cyclingnews.com he's tested positive for blood transfusions. There hasn't been any mention of medals & titles being stripped at this stage but I was just speculating about what might happen down the line if Tyler can't come up with a way to proove his innocence.

I hope it doesn't come to that. It's so disappointing. What would Tugboat think?

[jobob]

Supposedly the test can detect the presence of another person's blood in the test blood sample.

I don't know how this test is conducted, but I might do a little bit of digging around to find out.

My semi-educated guess is it would either detect DNA from another person's blood (via a PCR-type reaction) or detect antibodies the test subject generated against non-self proteins in the blood (via an ELISA).

Either way it would be looking for a very small signal in a very large background. Such tests are very tricky, prone to false positives and highly susceptible to operator error.

It would be a tragedy if a man's reputation and career were ruined on account of a test with questionable reliability.

I'm not saying it couldn't have happened; I'm saying that I'm not convinced yet.

Just my 2 cents.

[MightyMitre]

This link here gives a bit of background about the test.
http://www.cyclingnews.com/road/2004...eatures/doping

I think they normally do 4 tests altogether Set A x2 and Set B x2 to try and make sure the tests results aren't a fluke. On occasions riders have failed their A test but then the B test has then shown them clear.

Apparently this type of blood transfusion, when you take out your own blood then put it in again later was first used at the Los Angeles Olympics when it was still legal, so I suppose it's not like you're taking a banned substance, just putting back your own blood, but all sounds a bit grim. Wouldn't fancy it myself.

[spazzdog]

Just caught a blurb on the local news; it was a tidbit from a press conference, perhaps Phonak's. Tyler is vehemently denying the charges... I guess, like Lance, time will tell.

Maybe more will be on national news at 6:30... if they can get away from Bush's National Guard and Kerry's Viet Nam.

[jobob]

For those remotely interested, I ran a MedLine seach and came up with this report from a lab in Australia.

Flow cytometry is where cells are physically sorted based on the presence/absence of proteins on the surface of the cells which bind to various antibodies, which themselves are labeled, so the cells are sorted based on the presence/absence of a particular label.

I haven't figured out yet if this is the actual test now being employed. Interesting reading, nevertheless (if you're a nerd like me )

http://www.haematologica.org/2002_08/881.htm

Previous studies have shown that a greater than 5% increase in circulating hemoglobin is necessary to improve performance suggesting that athletes would need to infuse at least one unit of blood to obtain a surreptitious performance advantage. Assuming a blood volume of 4-5 L for an adult, transfusing a single unit of blood would result in approximately 10% of the red cell population being of donor origin. The antigenic profile of cells from any individual is under genetic control, and except in certain rare malignancies, hematopoiesis in the bone marrow produces red cells which have an identical and specific spectrum of blood group antigens.

In a clinical setting, the course of red cell engraftment after allogeneic bone marrow or peripheral stem cell transplantation may be followed by quantification of antigenically distinct donor and recipient red cells using flow cytometry. This technology has been used to determine the original phenotype of multi-transfused patients and to determine zygosity in paternity testing. Since the flow cytometer has a sensitivity of approximately 0.07%, this technology should be capable of detecting the transfusion of a single unit of blood, provided there is at least one antigen unmatched between donor and recipient. It should be noted that sibling transplant donors matched for histocompatibility A, B and DR antigens are rarely identical with regard to blood group antigens. Antibodies suitable for flow cytometry should be of class IgG, and some blood group antigens, notably A and B, M and N, stimulate a predominantly IgM response. It must also be assumed that blood intended for transfusion to athletes shortly before a competition would be matched for at least the groups ABO and Rh(D).

We report here the results from preliminary trials of phenotyping packed red cell samples, some of which were deliberately spiked with 10% red cells from another donor matched only for ABO and Rh(D). These samples were intended to mimic blood doping through transfusion. Both series were tested blind, the first using a panel of 10 antibodies (Table 1), and the second a panel of 12 antibodies (Table 2). Cells were labeled for flow cytometry through use of a secondary antibody, a fluorescein-conjugated sheep anti-human immunoglobulin.

In the first series, 6 of the 7 spiked samples and the 3 unadulterated samples were correctly identified. One spiked sample was not detected, and on closer examination the mixed bloods were found to be identical except for expression of the antigen S, for which no antibody was available at the time of testing. For the second series, there was clear evidence for 7 spiked samples and 3 unadulterated samples.

The chance of two blood samples matched for ABO and Rh(D) being identical for the panel of 12 blood group antigens is less than 1:500, the probability based on the most common phenotypic frequency of each antigen in a Western European population. Other populations may have a very different antigenic pattern and require a modified panel for testing.

Flow cytometry appears to be a technique capable of detecting homologous transfusion with a high degree of sensitivity. False positive results do not appear to present a problem. The half-life of transfused red cells is about 55 days and blood samples are stable for some weeks if refrigerated at 4°C. The technology thus seems well suited for application as a test method to detect homologous blood doping even 2-3 weeks after infusion.

[Adventure Girl]

AP is reporting that Phonak has suspended Tyler:

Phonak said Hamilton's suspension would hold "pending further notice'' until tests and proceedings are completed. "If Hamilton is not able to prove his innocence, then the contract will be canceled effective immediately''

Sad...

[aka_kim]

Whatever happened to "innocent until proven guilty"? And what happened to Phonak's staunch support of Tyler just yesterday?

[spazzdog]

Yep, it was just on local TV news...

Oh boy

[jobob]

What I find strange is that there was no follow-up test done on the Athens sample (and it's probably too late to test that sample now), and the follow-up test for the Vuelta sample was not done before the news broke. Very very shoddy, procedurally.

Even if the lone 'B' sample comes out negative, the damage has been done.

[jobob]

Wouldn't a team be required to suspend a rider upon learning of a positive doping test ?

I'm hoping that Tyler's suspension is just a formality required under the UCI anti-doping rules.

In the meantime, anyone have any rose-colored glasses they'd care to lend me?

[smurfalicious]

Originally posted by aka_kim
Whatever happened to "innocent until proven guilty"? And what happened to Phonak's staunch support of Tyler just yesterday?

Remember, we gave that right up when drug testing became an enormous money making industry. Not to take it to the extreme, but if our culture is willing to accept the idea of "you're guilty, please give us your hair, urine, etc to prove otherwise" why wouldn't we claim guilt right off the bat?

[jobob]

Here's another article describing the test (I'm pretty sure this is the test they're using) ...


http://www.haematologica.org/2003_11/1284.htm


Proof of homologous blood transfusion through quantification of blood group antigens

Margaret Nelson, Hazel Popp, Ken Sharpe, Michael Ashenden
Correspondence: Margaret Nelson, PhD,
Institute of Haematology Royal Prince Alfred Hospital, Missenden Road, Camperdown, NSW 2050 Australia.
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Background and Objectives
Athletes may illegally enhance endurance performance by transfusing homologous red blood cells (RBCs) and thereby increasing the oxygen carrying capacity of their blood. Detecting this dangerous practice is difficult by currently used methods. The aim of this work was to develop tests capable of detecting a mixed red cell population by flow cytometry, utilizing the likelihood of differences in minor blood group antigens.

Design and Methods
Twelve antisera directed against blood group antigens, derived from donor plasma, were used in conjunction with a secondary antibody directly conjugated with fluorescein to label IgG-coated RBCs. Optimal concentrations of RBCs and antibodies were determined on panel cells used in blood banking for the identification of specific antibodies. Blood samples from 25 patients purportedly transfused with 1-3 units of RBCs were screened for evidence of transfusion, and the percentages of antigen-positive and antigen-negative red cells were automatically calculated by the software installed in the flow cytometer after setting gates around these populations on histograms of fluorescence.

Results
Mixed RBC populations were identified in 22 of 25 patients tested. The three patients with antigenically homogeneous populations of RBCs were subsequently found not to have received their scheduled transfusions.

Interpretation and Conclusions
This technique can detect small (<5%) populations of cells that are antigenically distinct from an individual's own RBCs. These results show the potential for flow cytometry to identify illicit homologous blood transfusion in athletes, and suggest the risk of false positives may be low.

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