Transfusion-associated iron overload.

Iron overload develops mainly via two mechanisms, by a defect in the regulation of iron absorption (hereditary hemochromatosis) or by parenteral route (chronic red cell transfusion for anemic patients without blood loss) especially in patients with different categories of refractory anemias, and in anemic patients with chronic infection, alcohol excess, and malignancies. The accurate assessment of body iron is indispensable for the correct diagnosis and for finding the optimal treatment schedule for each individual patient. Liver biopsy with quantitative iron determination and histochemistry is still the reference method for the assessment of body iron status for patients with iron overload. New noninvasive measurements (hepatic magnetic susceptibility, CT, and magnetic resonance imaging) are still investigational procedures. It is important to decrease the need for transfusion by judicious use of red cell concentrates, make more widespread use of erythrocytapheresis, determine the red blood cell phenotype of the patient before the onset of a regular transfusion regimen, treat concomitant hepatitis infections, consider splenectomy to diminish red blood cell requirements, and early on consider allogeneic bone marrow transplantation for thalassemic patients who have HLA-identical siblings. It is advisable to screen for the hereditary hemochromatosis gene before starting any kind or regular red blood cell transfusion therapy, and to avoid if possible, the risk of free radical release by transfusional iron overload during the physiologically hypercoagulable state of pregnancy and its effects on the highly proliferative tissues of the fetus.

Blast colony forming cell-binding capacity of bone marrow stroma from myelodysplastic patients.

A specific stroma function can be quantitatively assessed by counting the stroma-adherent blast cell colonies (CFU-BL) that are formed from normal plastic nonadherent mononuclear bone marrow cells (PNAMNC) after a short-term coincubation ("panning") with the preformed stromal layer. In order to obtain information of stroma function in myelodysplasia (MDS), the "CFU-BL-binding capacity" of stroma from normal bone marrow and from patients with MDS were compared. Stromal cell cultures were established from mononuclear bone marrow cells in microplate cultures cultured with or without 10(-6) M hydrocortisone. CFU-BL-binding capacity was studied by counting blast colonies seven days after panning, and the results were expressed as CFU-BL/10(3) PNAMNC. Normal marrow stromal layers bound CFU-BL only if they were cultured with hydrocortisone, while MDS stromal layers also bound CFU-BL in the absence of hydrocortisone. For further studies of the function of MDS stroma, the effect of growth factors (stem cell factor [SCF], G-CSF, interleukin 3 [IL-3] and their combinations) on CFU-BL binding by normal or MDS stroma has also been compared. Twenty-hour incubation of the stromal layers with a standard dose (100 ng/ml) of various hemopoietic growth factors (IL-3 alone or in combination with SCF, G-CSF alone or in combination with SCF) did not have any effect on CFU-BL binding by normal marrow stroma, but increased the CFU-BL binding by stromal layers from MDS bone marrow. These findings suggest that although stromal microenvironment in MDS is capable of supporting hemopoiesis, bone marrow stroma from MDS patients differs in some characteristics from the normal stroma.

Longitudinal immunological follow-up of HIV infected haemophiliacs in Hungary.

Twenty-five haemophiliacs who had been infected with HIV in 1982 or 1983 were followed up from 1986 to 1993. The absolute number of the CD4+ and CD8+ cells, neopterin levels and more recently the percentage of activated, DR+ T lymphocytes were determined twice a year. In most patients a permanent decline in the CD4+ cell count was observed whereas in two HIV-infected haemophiliacs the absolute number of CD4+ cells did not change during the observation period. In these long-term non-progressor patients no clinical symptoms and no increased neopterin levels were observed. T cells subset and neopterin measurements were found to predict the development of AIDS. AIDS developed only in those patients who exhibited both a CD4+ cell count of < 350/microliter and a serum neopterin concentration of > 20 nmol/l. A negative correlation was observed between the percentage of activated. DR+ T lymphocytes and the CD4+ cell counts.

Prevalence and specificity of lymphocytotoxic antibodies in different stages of HIV infection.

Sera obtained from 27 HIV-infected persons were investigated for complement-dependent humoral cytotoxicity. Uninfected as well as HTLV-IIIB-infected H9 cells were used as cellular targets either before or after stimulation by phytohemagglutinin (PHA) or concanavalin A (Con-A). The degree of cytotoxicity was determined by 51Cr-release assay. Two different antibodies could be found in sera of HIV-infected persons, one being directed against HIV-induced cell surface component(s) and the other reacting with structure(s) present on activated T4 cells. Asymptomatic HIV-carries were found to have antibodies exerting complement-dependent cytotoxicity to HIV-infected T4 cells. These antibodies were reactive mainly after stimulation of HIV-infected target cells by Con-A. Sera of ARC and AIDS patients contained autoantibodies reactive with PHA-stimulated or HIV-infected T4 lymphocytes. These data suggest that HIV-specific antibodies represent an anti-viral immune defense, while autoantibodies may be important in destruction of the immune system in AIDS.

TCR gamma/delta bearing lymphocytes in peripheral blood of allogenic bone marrow transplanted patients.

The presence of two distinct T-cell receptors (TCR) alpha/beta and gamma/delta dimers as well as of the activated T cells was analysed in peripheral blood mononuclear cells from seventeen recipients of allogeneic bone marrow transplants for leukemia and for severe aplastic anemia. Nine of seventeen recipients expressed an elevated percentage of T cells bearing TCR gamma/delta receptors in their peripheral blood. Seven out of nine cases having elevated gamma/delta positive cells showed chronic graft-versus-host (GVH) disease; one patient was treated with Cyclosporin A, and one patient was asymptomatic. In the twelve patients with GVH or other clinical symptoms, activated T cells (CD3+/HLA-DR+) were elevated indicating an autoreactive or alloreactive cell population. Our results confirmed earlier in vitro data showing that TCR-gamma/delta-bearing lymphocytes may be an activated T-cell population, and this T cell subset might be involved in mediating GVH disease, or in prolonging immunodeficiency after transplantation.

Plasma desorption mass spectrometry of haemoglobin tryptic peptides for the characterization of a Hungarian alpha-chain variant.

S-Aminoethylated-alpha A and -beta A globin tryptic peptides separated by reversed-phase high-performance liquid chromatography have been analysed by plasma desorption mass spectrometry. Almost all the expected alpha A and beta A tryptic fragments were tentatively assigned relative to the known globin chain sequences based on the molecular weight obtained by plasma desorption mass spectrometric analysis of the purified peptides. The application of plasma desorption mass spectrometry for structure elucidation of a haemoglobin alpha-chain variant revealed the first case of Hb Hasharon in Hungary.

Neutralizing and complement-dependent enhancing antibodies in different stages of HIV infection.

Reclustering and indirect immunofluorescence assays on MT-4 cells [carrying both CD4 and complement receptor type 2 (CR2)] were used to measure neutralizing and enhancing antibodies in sera obtained from HIV-1-infected individuals. Heat-inactivated sera were tested before and after mixing 1:1 with fresh seronegative human serum. Using heated samples, neutralizing antibodies were found in 20 out of 20 and 11 out of 19 serum samples of asymptomatic and symptomatic [AIDS, AIDS-related complex (ARC)] HIV-seropositive patients, respectively. In complement-restored samples, neutralizing activity was found in eight sera of asymptomatic patients and in none of the sera of AIDS and ARC patients; enhancing activity could be detected in four and 12 sera, respectively. A significant positive correlation was observed between the titres of neutralizing antibodies measured in the complement-restored samples and the absolute number of CD4+ lymphocytes. These findings indicate that the appearance of complement-dependent enhancing antibodies coincident with the loss of neutralizing antibodies may indicate a poor prognosis in HIV infection.

Correlation of the percentage of activated, CD3 + DR + lymphocytes to serum neopterin level in HIV-seropositive haemophiliacs.

The percentage of activated, CD3+ DR+ and CD8+ Leu7+ lymphocytes and the serum neopterin concentration were determined in 17 HIV-seropositive and 10 HIV-seronegative haemophiliacs and in 11 healthy control subjects. All three parameters tested were found to be significantly higher in the seropositive patients than in the seronegative controls. In the seropositive group, a significant positive correlation was found between the neopterin levels and the percentage of CD3+ DR+ cells. By contrast, no significant negative or positive correlation was observed between the neopterin levels and the percentage of the CD8+ Leu7+ subset. These data suggest that in the HIV-infected patients the activated T cells responsible for the stimulation of macrophages to produce neopterin are those that do not carry CD8.

Gestión de servicios de transfusión de sangre / Gestión de servicios de transfusión de sangre / Management of blood transfusion services

La transfusión, sea de sangre entera o de algunos de sus componentes, es un elemento cada vez más importante en terapéutica, que atrae a un número cada vez mayor de especialistas. Pese a ello, el servicio de transfusión de sangre, y particularmente su gestión, suele constituir un sector relegado del servicio nacional de salud

Este manual da orientaciones completas sobre todos los aspectos de la gestión, desde la formulación de programas y políticas nacionales de sangre hasta el uso de sistemas automáticos de ordenación de datos. Algunos de los temas tratados, como son la inspección de la calidad, la prevención de la transmisión de enfermedades, la ética de la donación y la transfusión de sangre, y la contratación y el adiestramiento de personal, ofrecen un interés universal. Otros temas es posible que encuentren más aplicación en las circunstancias de los países en desarrollo, donde los recursos pueden ser escasos, la infraestructura de apoyo mínima y las comunicaciones difíciles. En el manual se facilitan ejemplos de métodos diversos que pueden ser adaptados o modificados según el orden de prioridad y las condiciones locales

Este manual, dada la amplia experiencia de sus autores tanto en los aspectos prácticos como en los administrativos, será en principio útil a todos los niveles de gestión para el establecimiento, la mejora o la ampliación de los servicios de transfusión de sangre

Changes in the expression of the cholinergic structures of human T lymphocytes due to maturation and stimulation.

We demonstrated that thymocytes have significantly lower AChE activity, no mAChR binding capacity and the same nAChR binding value, that we can measure on PBLs. The expression of all these structures was changed due to mitogenic stimulation. There is a strong evidence that cholinergic modulation may play a role in T-cell differentiation.

Neutralizing antibodies and serum interferon levels in the different stages of HIV infection.

The sera of patients infected with HIV were investigated for neutralizing antibodies (NA) and interferons. All samples from asymptomatic HIV carriers contained NA in high titres. In the sera of patients with AIDS related complex and AIDS the antibodies were found rarely and in lower titres. An early peak of acid-labile interferon (IFN)-alpha was observed in asymptomatic HIV-infected persons, and a late peak was found in AIDS patients. The data suggest that HIV NA may have beneficial effect in the asymptomatic phase. The presence of acid-labile IFN-alpha may indicate stimulation of IFN system by HIV-infected cells.

E. coli antibodies do not cause false-positivity in recombinant anti-HIV assays.

129 sera with known antibody titres against E. coli 026 and E. coli 055 strains were tested with the Abbot second generation anti-HTLV III recombinant screening assay. No difference in the O.D. values was found between sera with high, normal and low anti-E. coli titres. In addition, no false-positive reactions were observed with the anti-HIV negative sera containing E. coli antibodies in high titres in a Western blot assay in which recombinant env antigen was applied. These results suggest that E. coli assays in which E. coli-produced recombinant antigens are used.

Clinical value of cytomorphologic, immunologic and cytogenetic investigations of acute leukaemias.

The valuability of immunophenotyping of acute myeloid and lymphoid leukaemias in comparison to morphological and cytochemical classification were approached in 56 cases. In the case of acute myeloid leukaemias the immunophenotyping by monoclonal antibodies CD14, CD13, CD33 was less informative concerning the subtypes of the disease. The clinical diagnosis can be achieved on the basis of cytochemical investigation alone. In contrast, the diagnosis of lymphoid leukaemias requires all information obtained by immunophenotyping by a series of monoclonal antibodies CD3, CD2, CD4, CD8, CD1, CD19, CD20, CD21 and CD10. On the other hand, the monoclonal antibodies are essential in differentiation of the very immature myeloid and lymphoid leukaemias. This is of great importance from the clinical point of view for determining the therapy. Molecular genetic studies based on the characterisation of the state of gene rearrangement of immunoglobulin and T-cell receptor beta chains have basic importance in the confirmation of the result of immunophenotyping and in the determination of leukaemias of unknown origin.

Detection of Activation Antigens on Chronic Lymphocytic Leukaemia Cells.

The peripheral blood mononuclear cells of patients with chronic lymphocytic leukaemia were characterized by the presence of a variety of cell surface differentiation antigens. The cells of 20 patients were found to be of B-cell phenotype when studied with antibodies directed against CD19, CD20, HLA-DR and sIg. Furthermore, a significant percentage of the cells gave a positive reaction with the monoclonal antibody to CD5. On the other hand, the CLL-cells did not express the CD21 antigen (C3d receptor, EBV receptor). We studied in parallel the presence of various activation antigens using 19 monoclonal antibodies grouped into 7 clusters (CD25, CD30, CD40, CD69, CD70, CD39, CD71). A significantly higher percentage of the CLL cells expressed activation antigens than lymphocytes from healthy controls. The percentage of CD3/HLA + DR + cells, compared to the healthy control lymphocytes was not increased in the CLL patients, and the activated cells in CLL were found to have characteristics of B-cells. Based on these results, we suggest that the CLL cells, like the cells in Hodgkin's disease and T-cell lymphoma, are not resting, but activated B-cells or the neoplastic abberrants of activated cells.

Management of blood transfusion services / Management of blood transfusion services

Transfusion, of either whole blood or blood components, is an increasingly important element of medical treatment, and one that is attracting a growing number of specialists. Despite this, the blood transfusion service--and particularly its management--is too often a neglected area of the national health service

This manual provides a comprehensive guide to all aspects of management, from formulation of national blood programmes and policies to the use of automatic data processing systems. Certain of the topics covered, such as quality control, preventing the transmission of diseases, the ethics of blood donation and transfusion, and the recruitment and training of staff, are of universal relevance. Other subjects are likely to find greatest application in the context of developing countries, where resources may be scarce, supporting infrastructure minimal and communication difficult. The intention throughout the manual is to provide examples of various procedures, which may be adapted or modified to reflect local priorities and conditions

Drawing on the wide experience of its authors in both practical and administrative fields, this manual should be of value at all levels of management concerned with the establishment, improvement or expansion of blood transfusion services

Complement-dependent cytotoxicity of antibodies reactive with HIV-induced cell surface antigens in HIV-carrying haemophiliacs.

Sera obtained from HIV-infected as well as uninfected haemophiliacs and from healthy subjects were investigated for the presence of lymphocytotoxic antibodies. Using the 51Cr-release test, HIV-infected haemophiliacs were found to produce serum antibodies exerting complement-dependent cytotoxic effect on HIV-infected T4 cells. The antibodies were reactive mainly when HIV-infected target cells were stimulated with concanavalin-A. Results of complement-dependent antibody cytotoxicity and indirect membrane immunofluorescence tests suggest that envelope antigen(s) of HIV may be the target(s) for cytotoxic antibodies.

Effect of pepsin treatment on the HIV envelope and core antigens.

In order to clarify whether HIV-1 core and env antigens are destroyed during pepsin treatment, used previously for detecting HIV-1 core and env antibodies hidden in circulating immune complexes, purified recombinant env and core antigen preparations were treated with pepsin. Core antigen was found to be extremely sensitive to this enzyme. By contrast, the antigenicity of the purified env antigen was not destroyed and was even increased after pepsin treatment, performed under identical conditions. These findings suggest that after pepsin digestion the core-anti-core immune complexes do not reconstitute because of the loss of antigenicity of the core antigen. By contrast, the lack of binding after neutralization to the env antigen of the F(ab')2 fragment of the anti-env antibody, cleaved by pepsin from the immune complexes, is probably due to other factors.