Hodag

Because heparin is just evil. Seriously, heparin has been used for ages to process bone marrow and blood and the anticoagulant properties are well established. but the precise mechanism of action is undesirable since it is not easily reversible (we don't want to use protamine sulfate for example). Playing with citrate and CaCl concentrations gives the result we need, even if the process is a bit more complicated.

Thanks for the replies. This is for a stem cell isolate to be used eventually for transplant. Heparin is a non-starter for some very complicated molecular biology reasons that I won't detail, but CPD within certain limits may be acceptable. What is being attempted here is new technology. I definitely understand the problem of peripheral blood aspiration by the aspirating physician. Technique is all important, which is why we never let a hematologist aspirate "unsupervised". He might have an MD, but very few of them know how to get really good stem cell aspirates. FYI, we limit them to 2.5 ml per aspiration site and require use of at least a 20 ml syringe. Anything smaller syringe does not create enough suction when the plunger is yanked and the adherent cells, well, they stay adhered to the trabecular bone!

Please don't advertise in the forums. Thanks for your understanding.

I am not a BB tech like most of you, so I can use your help on a few things: 1. How does the hematocrit of peripheral blood compare with the hematocrit of aspirated bone marrow? 2. Same question as above, but for Ca2+ instead of hematocrit. 3. I know that glass tubes will trigger the contact activation coagulation cascade because of the anionic surface. How about plastic? If a quantity of bone marrow is aspirated into a typical plastic syringe to be almost immediately transferred into a collection bag containing an effective quantity of an anti-coagulant, do you need to pre-coat the syringe with a bit of anti-coagulant? I say "almost" immediately because the hematologist will typically aspirate from a few different sites with the time span of a few minutes, so the first pull may be in the syringe for 3-5 minutes.

Obviously you should have sent him to the Paviour's Finger. Better luck next time.