Succinylated gelatine: an alternative to hydroxyethyl starch for labelling leukocytes with 99mTc-HMPAO

Abstract

Hydroxyethyl starch (HES) is the most used plasma expander in the sedimentation of the erythrocytes during the radiolabelling procedure for leukocytes in vitro. To evaluate the usefulness of succinylated gelatine (GEL), another colloidal plasma expander, as an alternative to HES in this process. Two identical blood samples were obtained from 30 patients referred to white blood cell scintigraphy. The first sample was used to label leukocytes with Tc-HMPAO using the routine procedure, with HES. The other sample was used to label leukocytes with Tc-HMPAO using the same procedure, with GEL. The cell concentration of the leukocyte-platelet-rich plasma (LPRP) achieved after blood sedimentation was analysed. Labelling efficiency was calculated and the eosin Y viability and red cell/leukocyte ratio were evaluated from the final labelled cell suspension. Leukocytes and platelets recovered in LPRP were not statistically different between both HES and GEL samples (leukocytes: 8.10x10/microl+/-3.82 and 7.80x10/microl+/-3.47; platelets: 411x10/microl+/-182 and 406x10/microl+/-172, respectively). There were no significant differences between both agents on the labelling efficiency (HES: 80.3%+/-6.6%; GEL: 80.1%+/-6.3%), the eosin Y viability (HES: 99.2%+/-1.3%; GEL: 99.3%+/-1.1%) and the red cell/leukocyte ratio (HES: 1.21+/-0.7; GEL: 0.9+/-0.5). These results show that succinylated gelatine can be used instead of hydroxyethyl starch in the labelling of leukocytes with Tc-HMPAO.