Polymorphic and monomorphic HLA-DR determinants on human hematopoietic progenitor cells

The expression of monomorphic Ia-like antigens and polymorphic (allotypic) HLA-DR determinants on CFU-GM, BFU-E, CFU-E, and CFU-GEMM was studied in bone marrow and peripheral blood cells from normal healthy individuals. Using various polyclonal and monoclonal anti-Ia- like antibodies, the presence of HLA-DR backbone antigens was shown on all hematopoietic progenitor cells (HPC) studied, both in complement- dependent cytotoxicity assays and in fluorescence-activated cell sorting (FACS). The expression of allotypic determinants was demonstrated on all HPCs, using the HLA-DR typing sera anti-HLA-DR1, 2, 3, 4, 5, and 7. The Class II antigen MT-2 was also shown on all HPCs, using both monoclonal and alloantisera, whereas the MB-1 (DC-1) determinant could not be demonstrated on HPCs. This might open the possibility of removing MB-1-positive malignant cells from the graft in autologous bone marrow transplantation.     

A technique for the flow cytometric analysis of lymphocytes bearing histamine receptors

Histamine receptors have been demonstrated on lymphocyte membranes by a variety of techniques. We now report a method that allows for the flow cytometric analysis of histamine receptors on human peripheral T cells. Histamine is conjugated to fluoresceinated human albumin by the coupling agent ECDI. This conjugated histamine compound (FHA-his) binds to approximately 45% of T cells. Fluoresceinated human albumin alone (FHA), not conjugated to histamine, does not bind to T cells. In addition, unconjugated histamine can inhibit completely the binding seen with FHA-his. We conclude that this technique demonstrates specific FHA-his binding to histamine receptors on T cells and can be used to determine the number of cells bearing such receptors. In addition, the reagent could be used with a cell sorter to isolate distinct histamine-receptor-bearing (HR+) cells for further immunologic study.     

High-dose cytosine arabinoside and daunorubicin as consolidation therapy for acute nonlymphocytic leukemia in first remission: a pilot study

High-dose (HD) cytosine arabinoside (ARA-C) is more effective treatment than conventional-dose ARA-C regimens for patients with relapsed acute nonlymphocytic leukemia (ANLL). We report here that HD ARA-C given during the first remission of ANLL has resulted in long remission durations and a high proportion of patients who survive more than three years free of disease. From August 1979 to September 1983, 36 adult patients with ANLL in first remission received one to three courses of HD ARA-C (3 g/m2 by one-hour infusion every 12 hours for 12 doses on days 1 through 6) alone or with daunorubicin (30 mg/m2 for two or three doses on days 7 through 9). Three patients died of sepsis or hemorrhage during consolidation, and 14 patients have relapsed from five to 48 months after diagnosis. The remaining 19 patients are in continued complete remission (CCR) from 11 to 62 months. Denoting all deaths in remission as relapse, the actuarial probability of CCR is 42% at 62 months, with an apparent plateau in the survival curve. Of the first 22 patients treated, ten remain in CCR from 37 to 62 months with no therapy for at least three years. Due to its heightened anti-leukemic activity, HD ARA-C allows brief but effective consolidation of ANLL in first remission, with long-term disease-free survival comparable to other approaches.     

Sickle erythrocyte-endothelial interactions in microcirculation: the role of von Willebrand factor and implications for vasoocclusion

To determine the role of von Willebrand factor (vWF) in adhesion of sickle (SS) erythrocytes in microvascular flow conditions, we have perfused the ex vivo mesocecum vasculature of the rat with desmopressin, an analogue of vasopressin that causes the release of endothelial vWF. Analysis of vWF in the venous effluent of the isolated vasculature showed mainly the presence of extra-large molecular weight forms characteristic of endothelial vWF, which in the presence of desmopressin showed an average increase of 54%. Also, desmopressin induced a significant increase in adhesion of washed oxygenated (oxy) unseparated SS erythrocytes, accompanied by a persistent microvascular obstruction and a pronounced increase in the peripheral resistance (PRU). In contrast, infusion of SS deformable discocytes (SS2) in desmopressin-perfused vasculature resulted in a significant adhesion but not in persistent vasoocclusion, showing that SS2 discocytes alone are not sufficient for microvascular obstruction. Furthermore, SS4 erythrocytes (dense discocytes and irreversibly sickled erythrocytes) caused a persistent microvascular blockage and a significantly higher PRU than SS2 discocytes. However, the increase in PRU for SS4 erythrocytes following desmopressin treatment was 50% less compared with a corresponding increase for SS2 discocytes over the control values, which showed a smaller effect of desmopressin on the hemodynamic behavior of SS4 dense erythrocytes. Incubation of desmopressin-treated vasculature with anti-vWF antibodies resulted in a pronounced decrease in adhesion and significantly improved hemodynamic behavior of SS cells. Also, in untreated vasculature, similarly incubated with anti-vWF antibodies, there was almost complete inhibition of adhesion. Under the described perfusion conditions, antibodies to fibronectin and thrombospondin, as well as incubation of SS erythrocytes with anti-vWF antibodies did not affect adhesion. These results are compatible with a model for SS vasoocclusion in which extra- large vWF-mediated adhesion of deformable SS erythrocytes is the first step followed by an accelerated entrapment of dense SS erythrocytes.     

Lung findings on high-resolution computed tomography in idiopathic ankylosing spondylitis--correlation with clinical findings, pulmonary function testing and plain radiography

Previous studies on the association of ankylosing spondylitis and abnormalities of the lung parenchyma have been based largely on plain radiography and pulmonary function testing. This study, although uncontrolled, is the first to use high-resolution computed tomography to examine the entire lung parenchyma in ankylosing spondylitis patients, and to correlate the findings with clinical assessment, plain radiography and pulmonary function testing. The study population comprised 26 patients meeting the New York criteria for idiopathic ankylosing spondylitis who attended the out-patient department at our institution. High-resolution computed tomography examination revealed abnormalities in 19 patients (70%): these included interstitial lung disease (n = 4), bronchiectasis (n = 6), emphysema (n = 4), apical fibrosis (n = 2), mycetoma (n = 1) and non-specific interstitial lung disease (n = 12). Plain radiography was abnormal in only four patients and failed to identify any patient with interstitial lung disease. All patients with interstitial lung disease on high-resolution computed tomography had respiratory symptoms and three of the four had evidence of a restrictive process on pulmonary function testing. This study raises, for the first time, the possible association between interstitial lung disease and ankylosing spondylitis, and highlights the use of high-resolution computed tomography in detecting such disease in ankylosing spondylitis patients.      

Effects of testosterone administration on growth hormone pulse dynamics in human immunodeficiency virus-infected women

The effects of testosterone administration on the GH axis in androgen-deficient HIV-infected women are unknown. In this study, we determined the effects of transdermal testosterone administration on GH secretory dynamics and pulse characteristics in this population. GH-IGF-I parameters were determined in response to testosterone (4.1 mg/patch, twice a week; estimated delivery rate, 150 microg/d) vs. placebo over 6 months in 31 HIV-infected women. IGF-I increased significantly in the testosterone-treated compared with the placebo-treated patients [37 (-4, 73) vs. -30 (-98, 39) ng/ml, P = 0.01; 4.8 (-0.5, 9.6) vs. -3.9 (-12.8, 5.1) nmol/liter]. GH pulse frequency increased significantly in the testosterone-treated compared with the placebo-treated subjects [1.0 (1.0, 2.0) vs. 0.0 (-0.5, 1.5) peaks per 12 h, respectively; P = 0.02]. Before testosterone administration, overnight GH pulse amplitude was significantly related to IGF-I in univariate (r = 0.41, P = 0.03) and multivariate regression analysis; however, free testosterone, estradiol, and body mass index were not significantly correlated with baseline IGF-I. In contrast, after 6 months of treatment with testosterone, the change in IGF-I was significantly correlated to the change in free testosterone in univariate (r = 0.40, P = 0.04) and multivariate regression analysis. For each 1.0 pg/ml (3.5 pmol/liter) increase in free testosterone, IGF-I increased 19 ng/ml (2.5 nmol/liter), controlling for estradiol, body mass index, and GH pulse parameters (r(2) = 0.64). We demonstrate that IGF-I increases in response to physiologic, transdermal testosterone in HIV-infected women. The mechanism of this effect is unknown, but may involve a direct effect of testosterone on IGF-I, independent of changes in GH pulse dynamics.     

Interleukin 1 induces human marrow stromal cells in long-term culture to produce granulocyte colony-stimulating factor and macrophage colony- stimulating factor

Pure interleukin 1 (IL 1) was found to stimulate established human bone marrow stromal layers in long-term culture to produce colony- stimulating activity (CSA). Maximal concentrations in the culture medium were reached 24 hours after a single IL 1 pulse. The effect could be neutralized by a specific rabbit anti-IL 1 antiserum. Stromal layers, once stimulated by IL 1, continued to release CSA into the culture medium in the absence of exogenous IL 1. A second IL 1 pulse induced CSA release in an identical manner, as did the primary stimulation, indicating that the CSA released was actively produced. Using specific immunologic assays, both granulocyte colony-stimulating factor (G-CSF) and macrophage CSF (M-CSF) could be identified in the culture supernatants, and production of both factors was inducible by IL 1. Shortly after initiation of the long-term marrow cultures "spontaneous" G-CSF and M-CSF release occurred. The release of G-CSF diminished following addition of the anti-IL 1 antiserum, indicating that endogenous production of IL 1 by stromal cells had contributed to this effect. These results further support the role of IL 1 as an important modulator of CSF production by cells of the hematopoietic microenvironment.     

Hepatitis C virus infection and chronic liver disease in children with leukemia in long-term remission

Antibody to the recently identified hepatitis C virus (HCV) was investigated in sera of 50 leukemic children who had chronic liver disease (CLD), observed for 1 to 12.6 years after therapy withdrawal. All patients were tested for anti-HCV at regular intervals: Ortho- enzyme-linked immunosorbent assay (ELISA) test was performed in all cases. Reactive sera were also tested by recombinant immunoblotting assay to define the specificity of the results obtained by ELISA. Twelve cases (24%) were persistently positive (group A), 11 (22%) were transiently anti-HCV+ positive (group B), and 27 (54%) were negative. Mean SGPT peak during follow-up was significantly higher in group A (P = .014, A v B and P less than .00001, A v C). SGPT normalized off- therapy in 1 of 12 cases (group A), 10 of 11 (group B), and 19 of 27 (group C) (P = .0004, A v B and P = .012, A v C). Accordingly, liver histology, available in 37 patients, showed signs of chronic hepatitis in all patients in group A while most patients in group B and C had less severe liver lesions. These results indicate that HCV plays a significant role in the etiology of chronic hepatitis in leukemic patients and that persistent anti-HCV activity correlates with a more severe CLD, which could jeopardize the final prognosis of children cured of leukemia.