Detection of cell surface determinants for anti-Leu M3 (CD14), MY9 (CD33) and MY4 (CD14) and phagocytic function of cord blood monocytes in the course of gestational age.

To investigate immunological functions of cord blood cells, cord blood monocytes of 84 term and preterm newborn infants were examined in presenting cell surface determinants for the monoclonal antibodies anti-Leu M3 (CD14), My9 (CD33) and My4 (CD14) using an alkaline-phosphatase-anti-alkaline-phosphatase staining method. We also tested the phagocytic function of these cells by incorporation of Candida albicans in a 60 min incubation assay. Mean values for antigen expression ranged from 60 to 70%, whereby My4 showed a statistically significant higher level compared to Anti-Leu M3 and My9 (P = 0.05). Changes of antigen expression were statistically significant by the time of maturation. Statistically significant differences between male and female newborns were observed in 26-33 and 36-37 weeks of gestation. Considering the modus of delivery, no significantly higher amount of antigen-presenting monocytes were found in newborns of spontaneous birth compared to cesarean sections. However, no statistically significant differences in phagocytosis were observed between term and preterm newborn infants, mature newborns showed higher levels of both antigen expressing and phagocytic monocytes in contrast to a higher number of phagocytic cord blood monocytes only in premature infants.

[Bernard-Soulier thrombocytopenia: clinical significance of a rare disorder]. / Thrombozytopathie Bernard-Soulier: klinische Bedeutung einer seltenen Erkrankung.

We present 5 cases with thrombocytopenia and abnormal platelet function. The diagnosis of Bernard-Soulier syndrome was suspected in some subjects of advanced age on the ground of morphologic changes in the thrombocytes and of low platelet counts with or without prolonged bleeding time. The platelets showed normal aggregation with adrenalin, ADP and collagen but abnormal agglutination with ristocetine. All patients had normal von Willebrand factor levels in plasma. Flow cytometry demonstrated on thrombocytes lack of GP Ib expression of varying degree in comparison to normal controls, using various anti-GP Ib-antibodies (CD42b). The combination of these findings confirmed the diagnosis of Bernard-Soulier syndrome with varying expression of GP Ib. Flow cytometry and the use of specific monoclonal antibodies may be a rapid and reliable diagnostic tool. Differential diagnosis and treatment strategies are discussed. A congenital thrombopathy should always be considered in patients with thrombocytopenia of unknown origin and abnormal platelet morphology.

[How long should cyclosporin be administered following bone marrow transplantation?]. / Wie lange muss Cyclosporin nach einer Knochenmarktransplantation verabreicht werden?

After organ transplantation, life-long immunosuppression is mandatory to prevent rejection. This is not the case after allogeneic bone marrow transplantation (BMT). The mechanisms of tolerance are little understood and there is little data about the required duration of immunosuppression. In a retrospective study we analyzed the use of cyclosporine A (CyA) treatment in all BMT patients who where transplanted in Basel from 1979 to 1991. 243 patients with a median age of 26 (2-49) years received CyA to prevent graft-versus-host-disease (GvHD) and rejection. 206 patients had leukemia, 26 severe aplastic anemia and 10 a lymphoproliferative disorder. All were treated according to a common CyA regimen with initial parenteral administration followed by oral treatment for a year; after 1988 treatment duration was reduced to 6 months. Drug dosage was adjusted according to clinical symptoms, plasma levels and toxicity. At relapse of the original disease CyA was always withdrawn. Three months after BMT 96% were still on CyA. After 6 months 79%, after 1 year 61%, after 2 years 29%, after 3 years 18%, after 4 years 15%, after 5 years 8% and after 8 years 2% of patients were still taking CyA. All 20 patients who are still alive 10 years after BMT are off CyA. CyA was administered parenterally for a median of 31 (5-147) days. Oral treatment started at day 25 (4-28). The oral dose was reduced 5 (1-20) times, increased once (1-75) and finally discontinued after a median time lapse of 1 year (14d-8y).(ABSTRACT TRUNCATED AT 250 WORDS)

Additional GPI-anchored glycoproteins on human platelets that are absent or deficient in paroxysmal nocturnal haemoglobinuria.

In order to detect novel glycophosphatidylinositol (GPI)-anchored platelet proteins, human platelets were incubated with PI-specific phospholipase C (PI-PLC) and the supernatant was analysed by PAGE and silver-staining for additional protein bands. PI-PLC treatment resulted in the appearance of at least two additional novel GPI-linked glycoproteins (GP), GP500 and GP175, in the supernatant. Their presence on the platelet plasma membrane surface was demonstrated by periodate/[3H]borohydride surface-labelling. Activation of platelets did not enhance the amount of GP500 and GP175 that could be cleaved by PI-PLC. In Triton X-114 phase partitioning of platelet membranes the membrane form of GP175, mfGP175, was in the Triton phase while mfGP500 was found in the water phase. Neither GP500 nor GP175 were present in the supernatant of surface-labelled platelets treated with PI-PLC from 4 patients, diagnosed as having paroxysmal nocturnal haemoglobinuria (PNH), but the supernatant from platelets from healthy volunteers treated the same way contained both.