title: Influence of anticoagulants on the level of soluble HLA class I and class II antigens measured in blood samples.
abstract: The existence of soluble forms of HLA class I and class II antigens in human serum is well established and altered concentrations of these serum proteins have been described to be associated with various diseases. Since soluble HLA antigens (sHLA) can be measured both in serum and plasma samples, we investigated whether anticoagulant treatment influences the determined levels of soluble HLA class I (sHLA-I) or soluble HLA-DR (sHLA-DR). Analyzing paired samples of serum and plasma of 40 healthy individuals we found significantly lower serum levels of sHLA-DR (0.31 +/- 0.15 ng/ml) compared to EDTA plasma levels (0.58 +/- 0.20 ng/ml). By contrast, serum levels of sHLA-I (0.89 +/- 0.74 micrograms/ml) were only slightly lower than EDTA plasma values (0.95 +/- 0.86 micrograms/ml), a situation similar to that of sIL-2R and sCD4 levels. Further experiments intended to clarify the reasons of the reduced sHLA-DR serum levels revealed that (i) the blood storage time before centrifugation did not influence the sHLA-DR level, (ii) treatment of serum with anticoagulant did not augment the measured sHLA-DR concentration, and (iii) the recovery of spiked sHLA-DR was significantly lower when added to native blood than to serum or anticoagulant-treated blood. These results suggest that sHLA-DR is partly removed by the process of blood clotting thus resulting in diminished sHLA-DR serum levels.
authors.affiliation: Institut für Immunologie, Universität Rostock, Germany.
authors.forename: S
authors.initials: S
authors.lastname: Hausmann
authors.forename: R
authors.initials: R
authors.lastname: Claus
authors.forename: U
authors.initials: U
authors.lastname: Falk
authors.forename: S
authors.initials: S
authors.lastname: Wegener
mesh_terms: D000925:Anticoagulants / Q000494:pharmacology*; D015704:CD4 Antigens / Q000097:blood / Q000187:drug effects; D019343:Citric Acid / Q000494:pharmacology; D004492:Edetic Acid / Q000494:pharmacology; D004797:Enzyme-Linked Immunosorbent Assay; D006680:HLA Antigens / Q000097:blood* / Q000737:chemistry / Q000187:drug effects*; D006684:HLA-DR Antigens / Q000097:blood* / Q000737:chemistry / Q000187:drug effects*; D006493:Heparin / Q000494:pharmacology; D015395:Histocompatibility Antigens Class I / Q000097:blood* / Q000737:chemistry / Q000187:drug effects*; D006801:Humans; D015375:Receptors, Interleukin-2 / Q000097:blood / Q000187:drug effects
chemical_list: D000925:Anticoagulants; D015704:CD4 Antigens; D006680:HLA Antigens; D006684:HLA-DR Antigens; D015395:Histocompatibility Antigens Class I; D015375:Receptors, Interleukin-2; D019343:Citric Acid; D006493:Heparin; D004492:Edetic Acid