New assay promising for confirming anaphylaxis.

MIAMI BEACH -- Mast cell carboxypeptidase shows promise as a new clinical marker for anaphylaxis. Dr. Xiaoying Zhou and her associates reported at the annual meeting of the American Academy of Allergy, Asthma, and Immunology.

Assays for tryptase have proved useful in the diagnosis of anaphylaxis, but increased circulating levels of this mast cell product often cannot be detected. Using a pair of specific monoclonal antibodies, CA4 and CA5, British researchers have developed an enzyme-linked immunosorbent assay enzyme-linked immunosorbent assay

Any of various enzymes, including the proteinases and peptidases, that catalyze the hydrolytic breakdown of proteins.  that is released with tryptase by activated mast cells and is a mediator of inflammation.

The assay was applied to serum and plasma samples collected within 8 hours of the onset of an allergic reaction in 198 cases of suspected anaphylaxis and in 30 cases of systemic mastocytosis; control groups consisted of 209 healthy blood donors and 15 patients with bronchial asthma.

Carboxypeptidase levels were significantly higher in suspected anaphylaxis than in either control group. In some cases, concentrations were more than 100-fold greater, said Dr. Zhou of the University of Southampton In the most recent RAE assessment (2001)

Levels in the mastocytosis group also were greater than in the control groups in the study, which was funded by the Thrasher Research Fund in Salt Lake City and the London Law Trust.

"Our feeling is that the new assay will be useful in defining cases of anaphylaxis according to a biochemical criteria in addition to clinical assessments," lead author Dr. Andrew Walls commented in an interview. "The test should also be useful as a diagnostic aid in cases of mastocytosis and in other conditions in which mast cell activation is implicated."

In 83% of anaphylaxis cases with an elevated tryptase concentration, carboxypeptidase levels were above the normal range. Out of 110 cases of suspected anaphylaxis that were tryptase negative, 77 (70%) had an elevated concentration of carboxypeptidase, said Dr. Walls of Southampton General Hospital.

Arrangements have not yet been made with a commercial supplier to distribute the assay.

BY PATRICE WENDLING
http://www.thefreelibrary.com/New+assay+promising+for+confirming+anaphylaxis.-a0...

Hi Ramona ,

This is really good , as a tyrptase normal bod , this could have positive implications for me

Josie

Lisa wrote on 04/05/11 at 15:10:04:

Yes and no...

There is a lot of research going on about anaphylaxis... and that's a good thing!  Maybe my (peanut-allergic) son will benefit.  Even if the researchers can't figure out how to cure severe food allergies, maybe they could make them less life-threatening?! That would be awesome.

Unfortunately... some of us go into anaphylaxis for reasons that BOGGLE THE MINDS of most doctors.  Will this research pay off for people like me?  I hope so!!  I'm just not holding my breath

Heather

Hi Joan,

Yeah, I have heard about that study.  It's not a cure, but for people who have severe reactions to the tiniest bits of peanut it could be a lifesaver. The idea is that desensitization raises the threshold for a reaction... you still have to avoid peanuts, but you could tolerate small exposures like cross-contamination.  Fortunately... at least so far... my son's symptoms have been limited to hives and vomiting.  He hasn't fainted or stopped breathing (thank God).  We've done really well by cooking a lot at home and sticking to familiar places when we go out to eat.

Heather

Hey Jilly!!

I hope things are better for you!  I've been praying for you sweety!!!


As to this new assay, if you ask Dr. Castells she'll tell you, I'm sure!

And speaking about these assays, I was speaking with Dr. Guo-Ping Shi from B&W, he's a reasearcher in mast cells.  He told me that they've developed their own for tryptase!!!!  It's an ELISA too.  If you want, I'll be glad to send you his email cause he's gotten interested in us masto patients and I'm sure he'd LOVE to talk with you!!   Who knows, maybe they've even got some jobs available!!   How would you like the idea of moving to Boston and Harvard????!!!!   Let me know!

Hugs!

Lisa

Sorry about the shocking Sweety!!   I'm sure it's all the stress you are under!!   I would LOVE to see you out from under it!!!!

I'll give you his email.  Write to him!  Let's see if he can help you.  I know his boss, write to her and let's see if she may have an opening too!!

Lisa

Good for you Josie!!  Way to go!!!   It's good for them to know that we are VERY interested in their work cause it encourages them to keep seeking for answers for us patients!!