J A Loos — Page 3 | PubMed Health

PubMedDate not supplied

Large scale preparation of leukocyte concentrates and further purification of lymphocytes and granulocytes with the IBM 2991 cell processor.

A procedure is described for the large-scale production of pure suspensions of human lymphocytes and granulocytes. Platelet-poor buffy-coats, obtained by centrifugation of six units of ABO-compatible ACD blood, were pooled and centrifuged again, resulting in a crude leukocyte concentrate containing approximately 60 per cent of the original amount of leukocytes. Further fractionation of such crude leukocyte concentrates was achieved by scaling up Bøyum's Ficoll-Isopaque density gradient technique with the aid of an IBM 2991 blood cell processor. In this way 2.9 +/- 0.3 X 10(9) mononuclear leukocytes, consisting of 90 +/- 0.7 per cent lymphocytes and 5.3 +/- 0.3 X 10(9) polymorphonuclear leukocytes of 92 +/- 0.7 per cent purity could be isolated in one run. The overall yield was 36 per cent of the original amount of leukocytes.

Centrifugation, Density Gradient↗

PubMedDate not supplied

Effect of pre-incubation at 37 degrees C of platelet concentrates on the post-transfusion platelet adhesion capacity to collagen and fibrinogen.

The effect of warming (37 degrees C) of stored platelet concentrates (PC) on the post-transfusion platelet function as measured by the adhesion capacity in a rectangular perfusion system under flow conditions was analyzed in 22 patients undergoing transfusion for stable thrombocytopenia. Nine patients received a PC stored at 22 degrees C and incubated at 37 degrees C for 1 h before transfusion, 10 patients received a non-warmed PC, 3 patients received both a pre-warmed and a non-warmed PC. In the PC the platelet adhesion capacity to collagen was higher in the pre-warmed PC than in the non-warmed PC (33 +/- 5.9% coverage vs. 22 +/- 4.7% coverage, respectively, in a selected group with the same platelet concentration). The adhesion capacity to collagen of the platelets in the patient's blood, measured 10 min after transfusion, had increased considerably in both patient groups and 4 h later the adhesion capacity in both patient groups was similar to that of the pre-warmed PC before transfusion. We conclude that though pre-warming of stored PC had a beneficial effect on the adhesion capacity to collagen of the platelets in the PC, the clinical significance is questionable because already 10 min after transfusion the adhesion capacity to collagen of stored non-warmed platelets had improved to the level of the pre-warmed platelets and 4 h after transfusion this improvement was still present.

Adult↗