Percutaneous transhepatic placement of a Hickman catheter.
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Adult↗
Biomedical subjects
P Carlson
Publications and source records attributed to P Carlson.
HL-60-1E3, a novel phorbol diester-resistant HL-60 cell line.
The HL-60 (human promyelocytic leukemia) cell line has proved to be a useful model for the study of the expression of cellular functions and markers associated with hematopoietic differentiation. We report here the development and initial characterization of a novel, differentiation-resistant HL-60 cell line (HL-60-1E3) which was established by cloning the parent HL-60 line in the absence of mutagens or differentiation-inducing agents. HL-60-1E3 exhibits markedly reduced phorbol diester-induced expression of extracellular cytolytic activity, nonspecific esterase, phagocytosis, and surface Mo1 antigen. In addition, dimethyl sulfoxide-induced expression of both Mo1 and Mo2 is markedly reduced. However, if HL-60-1E3 is exposed to dimethyl sulfoxide, it acquires appreciable phorbol diester-triggered cytolytic activity and production of superoxide anion (O2-). Phorbol diester receptor number and dissociation constant (Kd) obtained by Scatchard analysis are not significantly different for the two cell lines. The HL-60-1E3 cell line should provide a useful adjunct to other cell lines used in the study of normal myeloid and leukemic cell differentiation, as well as the study of cytokine maturation factors and oncogene expression.
Antibodies, Monoclonal↗
von Willebrand factor is present on the surface of platelets stimulated in plasma by ADP.
von Willebrand factor (vWf) can bind to glycoprotein (GP) IIb/IIIa on activated platelets. The significance of this interaction is unclear, however, because it has not been possible to detect vWf binding to GPIIb/IIIa on platelets stimulated in plasma. We have developed an indirect, flow cytometry assay that uses fluorescein-labeled antibodies to detect vWf and fibrinogen on platelets. Using this assay, we found vWf on the surface of platelets stimulated in plasma by ADP. The number of platelets that bound vWf increased in proportion to ADP concentration and incubation time. Washed platelets in a protein-free buffer activated by 1 mumol/L calcium ionophore A23187 or 10 mumol/L ADP also bound vWf, suggesting that we were detecting surface binding of alpha-granule-derived vWf. Monoclonal antibodies against the vWf binding site on GPIb (6D1) and the vWf and fibrinogen binding sites on GPIIb/IIIa (LJP5 and LJ-CP8, respectively) were used to characterize the mechanism of vWf binding to stimulated platelets. Ristocetin-induced binding of vWf was inhibited by 6D1, and ADP-induced binding of fibrinogen was inhibited by LJ-CP8. None of these antibodies inhibited ADP-induced vWf binding. Aspirin and prostaglandin E1 also inhibited ADP-induced binding of vWf in platelet-rich plasma. During platelet activation in plasma, vWf derived from alpha-granules becomes bound to the platelet surface possibly being transferred already associated with a binding site.
Adenosine Diphosphate↗
A naturally occurring, warm-reactive macroglobulin specific for papain-treated human platelets: preliminary characterization.
Sera from 28 of the 113 normal children and adults (25%) studied were found to contain an immunoglobulin capable of causing complement-dependent lysis of normal platelets treated with small quantities of papain. This factor reacts equally well at 4 degrees C and at 37 degrees C with a determinant induced on platelets from normal subjects by treatment with papain or bromelain, but not by trypsin, chymotrypsin, or neuraminidase. It does not bind to red cells treated with any of these enzymes. The site(s) for which the factor was specific could not be induced on platelets from six patients with type I Glanzmann's thrombasthenia (lacking glycoproteins IIb and IIIa), in contrast to platelets from each of 20 normal donors. Isolation and characterization of the factor has been difficult because of its intolerance to chemical and physical manipulation. In 11 of the 20 individuals studied, however, it was found to have the properties of an IgM immunoglobulin. The factor appears to be different from any previously described, naturally occurring human immunoglobulin. It has not yet been shown to be associated with any disease state, but in the presence of complement, it is capable of causing profound damage to platelets previously subjected to minimal proteolysis, and the possibility that it can provoke platelet destruction in some conditions deserves further study.
Adolescent↗
Helping parents cope. A model home-care program for the dying child.
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Adaptation, Psychological↗
Solubilization of an activity regulating C3b function from Raji cell membranes.
A fraction of isolated Raji cell membranes solubilized with 2m KBr which was capable of inhibiting C3-dependent rosettes was examined for its ability to inhibit the alternative pathway of complement. It was shown to decrease alternative pathway-dependent haemolysis of sheep erythrocytes and to accelerate decay of factor B from these cells. It had no effect on C2 decay, the classical pathway analog of factor B. Inhibitory activity solubilized from Raji cells was not removed by immunoadsorption with anti-factor H or anti-factor I, two well-characterized serum C3b-control proteins. It also differed in two functional respects from these proteins. Firstly, it failed to result in cleavage of a peptide bone in C3 which is characteristic of factor I; secondly, its inhibitory activity did not synergize with factor I in inhibiting the alternative pathway, unlike factor H. These results suggest that Raji cells contain a regulatory factor in their membranes for the alternative pathway of complement which is distinct from factors H and I.
Burkitt Lymphoma↗