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Changes of lipoprotein composition have been mainly reported in conditions of sepsis. This study characterized compositional changes in LDL and HDL during the acute phase response following cardiac surgery with cardiopulmonary bypass. Twenty-one patients undergoing cardiac surgery were included in this study. Blood samples were drawn before operation and on day 2 post-surgery. In parallel to plasma lipids and antioxidant status, lipoproteins were analyzed for lipid, apolipoprotein (apo), hydroperoxide and alpha-tocopherol content. Beyond decreases in lipid concentrations and antioxidant defenses, cardiac surgery induced substantial modifications in plasma lipoproteins. ApoB decrease in LDL fraction (-46%; P < 0.0001) reflected a marked reduction in the circulating particle number. LDL cholesteryl ester content relative to apoB concentration remained unchanged post-surgery while triglyceride (+113%; P < 0.001), free cholesterol (+22%; P < 0.05) and phospholipid (+23%; P < 0.025) were raised relative to apoB indicating increased particle size. In HDL, an abrupt rise of apoSAA (P < 0.05) was observed together with a decrease of apoA1 (-22%; P < 0.005). Cholesteryl ester content in HDL fraction decreased in parallel to apoA1 concentration while triglycerides, free cholesterol and phospholipids increased relative to apoA1. In contrast to unchanged alpha-tocopherol content, hydroperoxide content was increased in LDL and HDL. By comparison to sepsis, cardiac surgery induces a comparable reduction in circulating LDL but a more limited decrease in HDL particles. Furthermore, in contrast, cardiac surgery induces an increase in polar and non-polar lipids, as well as of particle size in both LDL and HDL.

A rapid supply of n-3 polyunsaturated fatty acids (PUFA) may be indicated in some acute conditions because of the ability of n-3 PUFA to decrease inflammatory responses and cell sensitivity to various stimuli, and to improve endothelial dysfunction. To achieve these objectives, n-3 PUFA content needs to be quickly raised in cell membranes of key organs. Intravenous fish oil (FO) emulsions are available but their slow hydrolysis limits their infusion rate. Mixtures containing both FO triglycerides and medium chain triglycerides may overcome this problem. These new preparations are rapidly cleared from plasma and efficiently deliver n-3 PUFA to several tissues, largely via direct particle uptake. Recent data suggest that n-3 PUFA incorporation in phospholipids promptly modulates important cell functions. This review also focuses on a novel approach to rapidly supply n-3 PUFA to targeted organs which may offer interesting perspectives in the management of acute illnesses.

Cardiac surgery was associated with a marked reduction in circulating LDL and HDL particles, which in turn largely affectd alpha-toc transport. alpha-toc was decreased in WBCs but not in PLTs and RBCs. An increased hydroperoxide content was observed in LDL and possibly in HDL after cardiac surgery.

A new pentacyclic triterpene, 11alpha-acetoxy-20,24-epoxy-25-hydroxy-dammar-3-one (1), has been isolated from the African tree Combretum nigricans, together with the known corresponding diol, 20,24-epoxy-11alpha, 25-dihydroxy-dammar-3-one (2). They are responsible, at least in part, for the cytotoxic activity of the methanolic extract of the plant.

We recently demonstrated that azodicarbonamide is an immunosuppressive compound that inhibits calcium mobilization in T lymphocytes. In this study, we show that azodicarbonamide prevents the progression of human CD4+ T lymphocytes into the G1 phase of the cell cycle, inhibits their blastogenesis, down-regulates their membrane expression of CD25 and CD69, and decreases their transcription of cytokine genes. Addition of the calcium ionophore A23187 completely restores T cell proliferation in the presence of azodicarbonamide. Furthermore, azodicarbonamide synergizes with cyclosporin A to inhibit CD4+ T cell proliferation. In conclusion, the immunosuppressive action of azodicarbonamide is mainly related to its effect on the calcium mobilization machinery and is synergistic with that of calcineurin inhibitors., (Copyright 2001 Academic Press.)

The study aimed to investigate whether, during short term infusion of lipid emulsions in man, red blood cell (RBC) membrane lipid composition was altered and RBC-free cholesterol (FC) could serve as a source of FC accumulated in the plasma. 3 normal subjects were infused intravenously with either 10% Intralipid [10% IL; PL:triglyceride (TG) weight ratio of 0.12] at the rates of 0.1, 0.2 and 0.3 g TG.kg(-1).h(-1) (providing PL intakes of 12, 24, 36 mg.kg(-1).h(-1), respectively) or with 30% Intralipid (30% IL; PL:TG ratio of 0.04) at the rate of 0.3 g TG.kg(-1).h(-1) (providing 12 mg PL.kg(-1).h(-1)). Infusion of 10% IL at a slow rate and 30% IL at a high rate caused no change in RBC and plasma FC content. However, 10% IL infusion at intermediate and high rates induced a significant decrease in RBC-FC: PL ratio. This change was still present at 18 h after the cessation of high rate infusion. RBC-FC: PL ratio and plasma PL measured during infusion were significantly correlated (r = -0.87, p < 0.001). FC efflux from RBC appears to contribute to the rise in plasma FC. This study indicates that the excessive amount of PL present as liposomes in some intravenous lipid emulsions can alter erythrocyte membrane lipid composition.

The effect of the long-term intravenous infusion of 2 lipid emulsions, differing in essential fatty acid (EFA) content, on fatty acid pattern of red blood cell (RBC) was investigated in 5 patients with inflammatory bowel disease. They were randomly assigned to receive daily intravenous infusion of either a soybean emulsion or a mixed medium-chain triacyl-glycerols (MCT): soybean emulsion, followed by the other, each for a period of 3 months. The soybean emulsion contained exclusively long-chain triacylglycerols (LCT) with 54% of C18:2n-6 and 6% of C18:3n-3. The mixed emulsion consisted of a 50:50 (w:w) mixture of soybean LCT and MCT, providing half the amount of the same EFA compared to LCT emulsion. The same phospholipid emulsifier was used in both preparations. Infusion of LCT for a 3 month period modified RBC fatty acid pattern as follows: 18:2n-6 increased, 20:4n-6 decreased as well as n-6:n-3 ratio. By contrast, infusion of MCT/LCT did not alter RBC fatty acids, and even tended to correct a pattern altered by the previous LCT infusion. The study demonstrates that soybean LCT provides an excess of C18: 2n-6 which affects the balance between RBC fatty acids in adult patients. Decreasing the intake of C18:2n-6 and C18: 3n-3, by using a mixed MCT/LCT emulsion, appears more appropriate for keeping a balanced pattern.

The objective of this study was to analyze monokine production by peripheral blood mononuclear cells from patients with alcoholic cirrhosis. The capacity of peripheral blood mononuclear cells and purified monocytes from these patients to produce tumor necrosis factor alpha, interleukin 1 beta, and interleukin 6 was investigated. Spontaneous production of tumor necrosis factor alpha, interleukin 6 and interleukin 1 beta was similar in cirrhotic and healthy subjects, but serum levels of interleukin 6 (less than 2 U/ml vs. 9.5 +/- 3 U/ml) and tumor necrosis factor alpha (3.1 +/- 1.2 pg/ml vs. 12.0 +/- 1.2 pg/ml) were significantly higher in cirrhotic patients. However, peripheral blood mononuclear cells or purified monocytes from patients with alcoholic liver cirrhosis, stimulated in vitro with Escherichia coli lipopolysaccharide, displayed a marked increase of tumor necrosis factor alpha, interleukin 1 beta and interleukin 6 secretions compared with healthy controls. A striking feature of this overproduction was its reversibility as assessed by allowing cells to rest in vitro without lipopolysaccharide for 1 to 7 days before stimulation. In such conditions, tumor necrosis factor alpha and interleukin 6 secretions declined to levels present in healthy subjects in whom production remained stable, whereas interleukin 1 beta secretion markedly decreased in both groups to the point where no difference could be seen. This reversible oversecretion of cytokines after lipopolysaccharide stimulation, along with the lack of abnormality of spontaneous cytokine secretion, suggests that monocytes in these patients may have undergone an in vivo activation process analogous to a priming phenomenon. The in vitro activation with lipopolysaccharide may represent the correlate of in vivo endotoxemia observed during acute events such as sepsis.(ABSTRACT TRUNCATED AT 250 WORDS)

The influence of Broncho-Vaxom (BV) on different immune parameters was investigated in vitro on human peripheral blood mononuclear cells (PBMC). It was found that BV enhances the natural killer (NK) activity of PBMC and increases their spontaneous and phytohemagglutin (PHA)-induced production of tumor-necrosis factor--alpha and interleukin-2 as well as the PHA-stimulated production of interferon-gamma. These immunostimulating actions of BV on NK activity and cytokine production can contribute to the understanding of the enhancement of the body's defense mechanisms against respiratory tract infections.

The influence in vivo of immunosuppressive drugs (cyclosporine, azathioprine, and corticosteroids) on the production of various lymphokines (alpha and gamma interferon, interleukin 2), both in organ transplant recipients and in normal volunteers taking 100 mg hydrocortisone orally has been studied. To avoid interference with the rejection process or viral infection, patients were studied in a steady state with low maintenance immunosuppression consisting of prednisolone combined with azathioprine or with cyclosporine. In patients treated with both drug regimens, significant depression of production of the three lymphokines was found. Normal volunteers challenged with 100 mg hydrocortisone showed inhibition of production of interleukin 2 and alpha and gamma interferon in 4 hr, a time corresponding to the nadir of T cell lymphopenia, affecting the OKT4 subset preferentially. The percentage of OKT8 cells remained unchanged. Percentages of large granular lymphocytes increased, but their absolute number was not significantly modified. Changes in lymphocyte markers were fully reversible after 24 hr, but interleukin 2 production remained markedly depressed, showing that the redistribution patterns induced by corticosteroids on lymphocyte subsets may be dissociated from functional consequences.

Active and late rosette-forming cells, separated on the basis of their different affinities for SRBC, were tested for their ability to react with monoclonal antibodies of the OKT series. No significant preferential distribution of T subpopulations defined by these reagents was found in the high affinity E rosette fraction, while in the low affinity T cell subset the major finding was a high number of cells lacking both OKT4 and OKT8 determinants. This seems to be related to methodology, as indicated by experiments in which sequential cycles of rosetting procedures were found to induce loss of reactivity with OKT monoclonal antibodies. The implications of these methodological observations are further discussed.

An immunogold staining procedure for light microscopic enumeration of peripheral blood lymphocyte subsets defined by monoclonal antibodies (OKT3, OKT4, OKT8, OKIa1, Leu 1, Leu 4, Leu 2a, Leu 3a, Leu 10, Leu 12, B1) is described. It uses colloidal gold-labeled goat anti-mouse Ig (GAM G40 and GAM G30) as second layer and a methyl-green pyronin counterstain. Performed on small volumes of blood without sophisticated laboratory equipment, this method allows accurate cell type recognition and permanent records, essential for longitudinal observations. By enumerating the gold particles on positively labeled cells, it was shown that the staining reactivity depended on the monoclonal antibody used. Lymphocytes reacting with OKT8 or OKIa1 or B1 exhibited the strongest labeling whereas OKT4+ cells were weakly labeled. When compared with flow cytometry analysis in healthy subjects, the accuracy, precision and sensitivity of both methods were very similar. Similarly, a close correlation (97%) was found between immunogold staining and immunofluorescence microscopy in 35 patients with various diseases suggesting that immunogold staining may be useful in a clinical context.

This study reports the in vitro influence of morphine, dextromoramide, levomoramide, and methionine-enkephalin upon normal human T blood lymphocytes by using the active and total rosette tests. Morphine and dextromoramide inhibited the percentage of active T rosettes. This effect was completely reversed in the presence of naloxone, their specific antagonist. The specificity was further demonstrated by the absence of the effect of levomoramide, the inactive enantiomere, upon the rosette system. Methionine-enkephalin increased the percentage of active T rosettes. This effect was specifically inhibited by naloxone. These observations suggest that normal human blood T lymphocytes bear surface receptor-like structures for morphine, dextromoramide, and methionine-enkephalin. Such findings may provide a link between the central nervous system and the immune system.

Broncho-Vaxon (OM-85 BV) is a bacterial extract of eight bacterias usually involved in the respiratory tract infections. Since Broncho-Vaxom is clinically active in decreasing the incidence of such infections, its immunological effect was investigated, in vitro, using peripheral blood mononuclear cells (PBMC). The experimental data indicate that Broncho-Vaxom can modulate various immune functions. It was shown, using a radioimmunoassay for these cytokines, that Broncho-Vaxom will spontaneously enhance TNF alpha and IL-2 production whereas it has no action on IF gamma production. However, when the PBMC are stimulated with PHA, an increased production for IF gamma, TNF alpha and IL-2 was observed suggesting that, under appropriate conditions, Broncho-Vaxom enhances the production of these cytokines. In other experiments, Broncho-Vaxom was shown to markedly increase the natural killer activity of PBMC. All these results demonstrate that Broncho-Vaxom is an immunomodulator affecting multiple immunological mechanisms including the activation of natural killer cells, of monocytes and of T cells through direct mechanisms or through the cytokine cascade.

Determination of fetal red blood cell Kell antigen is possible on fetal red blood cells obtained at 10 weeks of gestation by chorionic biopsy and may contribute to the management of severe Kell-hemolytic disease.

This article summarizes the hematological and immunological consequences of splenectomy in children. The hematological consequences are mainly noticed in the number of white cells and platelets. Indeed, platelets can remain elevated several weeks and even several months after surgery. Rarely antiplatelets aggregant drugs will be given if the platelet count is higher than one million per cubic millimeter. The immunological consequences of splenectomy in children are mainly manifested if the surgery was performed before the age of 6 or 7. The major consequence is a rapid and often lethal infectious complication. In diseases like thalassemia major or lymphoma, there is an increased risk of infection. The immunological mechanism seems linked to a decreased antibody formation in presence of higher antibody titre needed by the reticuloendothelial system to eliminate the microorganisms responsible for the infection. Therapeutic measures can be proposed: delay the age of splenectomy, leave some splenic tissue, administration of penicillin and lastly immunization against some antigens mainly responsible of the infection.

The peripheral lymphocytes of a patient with prodromal acquired immune deficiency syndrome contained giant multivesicular bodies. These were specifically stained by immuno-gold labelled polyclonal antibodies against the major core protein p24 of bovine leukaemia virus and human T cell leukaemia virus I. Moreover, the patient's serum was positive for bovine leukaemia virus by the ELISA method.

Lynestrenol, a synthetic steroid progesterone-like substance, has been found to enhance the stimulation of normal human lymphocytes. It increases the phytohemagglutinin response and the mixed-lymphocyte cultures. This augmentation can, in some cases, be higher than 100% of the phytohemagglutinin or mixed lymphocyte reaction baseline. There is no significant effect on the pokeweed mitogen stimulation. It is concluded that lynestrenol can modulate, "in vitro", some T cell functions.

In vitro effects of three immunosuppressive drugs, cyclosporin, methylprednisolone, and 6-mercaptopurine (the active moiety of azathioprine), have been assessed by various proliferative assays including mixed lymphocyte reaction (MLR), concanavalin A (Con A), OKT3 monoclonal antibody (MoAb), phorbol myristate acetate (PMA), and A23187 ionophore-induced mitogenesis. The influence of these drugs on the capacity to produce interleukin-2 (IL-2) after phytohemagglutinin (PHA) induction has also been evaluated. Depending upon the nature of the stimulus used, differences were found among the three immunosuppressive drugs, suggesting that different T-cell activation mechanisms are involved. The response to alloantigens (MLR) or to mitogens (Con A and OKT3 MoAb) resulted in significant inhibition by all three immunosuppressive agents, although 6-mercaptopurine was somewhat less potent at the pharmacological concentration of 0.1 microgram/ml. When PMA (which activates cells through protein kinase C) and A23187 ionophore (which enhances Ca2+ influx into the cytoplasm through membrane channels) were used, dissociations were observed, suggesting that drugs act differentially on early stages of T-cell activation. Inhibition of PMA-induced activation by cyclosporin was very limited in contrast to the potent effect of methylprednisolone. The latter drug could thus preferentially affect an activation step involving the PMA receptor. Furthermore, the inhibitory influence of methylprednisolone on A23187 ionophore-induced proliferation was equivalent to that of cyclosporin, while 6-mercaptopurine had no effect except at the high concentration of 1 microgram/ml in which direct inhibition of DNA replication is probably involved. IL-2 production induced by PHA was strongly blocked by methylprednisolone and cyclosporin but not by 6-mercaptopurine, at least when a pharmacological concentration was used. In view of the relative independence of ionophore-induced activation from the influence of IL-2, this response could be linked to the intrinsic mechanism of antiproliferative activity of immunosuppressive drugs which probably act mostly at the level of IL-2 production. These results also provide a cellular approach to the synergies between immunosuppressive drugs. Most of the tests are more strongly affected by cyclosporin than by 6-mercaptopurine, probably explaining the potent steroid-sparing effect of cyclosporin.

The effect of vinblastine and colchicine on human blood T cell rosette formation with sheep erythrocytes was assessed. For some concentrations, both drugs increased the percentage of active T rosettes. In contrast, the total T rosette percentage was decreased by the same drugs. These experiments further confirm the heterogeneity of T cell rosettes and suggest the existence of three types of sheep red blood cell receptors on human blood T lymphocytes.

High levels of tumor necrosis factor-alpha, interleukin-2, and gamma-interferon appeared in the circulation of kidney transplant recipients after the first injection of the monoclonal antibody OKT3. This initial injection was systematically followed by fever. The three cytokines were released in all patients (n = 9), with peak serum levels of tumor necrosis factor occurring 1 hr after OKT3 injection and those of interleukin-2 and gamma-interferon after 2 hr. Cytokines were not released after the second and third OKT3 injections, when CD3+ cells had disappeared from blood. These findings suggest that circulating cytokines are released by T cells after activation by OKT3. These cytokines are probably involved in the systematic reactions observed after injection of OKT3.

Immune-mediated mechanisms and genetic factors are believed to be involved in the pathogenesis of Crohn's disease. We studied T- and B-cell subpopulation proportions and various functional assays, including proliferative responses to PHA and Con A, Con A-induced suppressive activity, and natural killer cell assay toward the K562 cell line, in the peripheral blood of 22 patients with inactive familial Crohn's disease and their 35 healthy relatives including nine families. HLA-A, -B, and -DR antigens were determined in all the subjects. With the exception of minor abnormalities of suppressor cell activity present in some relatives of two families, neither significant impairments of immunological parameters in patients or their relatives nor concordant segregation of HLA haplotypes and disease were observed. These data indicate that peripheral immune abnormalities previously described in patients with Crohn's disease do not constitute primary factors involved in the disease itself and that familial incidence in Crohn's disease cannot be linked to immunological markers presently studied.

We report a case of a double M component appearing in the course of angioimmunoblastic lymphadenopathy with dysproteinemia (AILD). Lymphocyte function, especially the decrease in T-suppressor cells, could play an essential role in the mechanisms of the disease. In the presence of an M component, the prognosis for AILD seems to be more pessimistic. Arguments for considering AILD as a premalignant disease are reviewed.

A new approach to rapidly determine human mixed-lymphocyte culture (MLC) is presented. It is based on the identification of an early increase in the percentages of active T rosettes (TEa) in the MLC tubes. Active T rosettes represent a subset of T cells with high-avidity receptors for sheep red blood cells. All subjects tested had a full determination of their HLA-A, -B,-C, and -D-DR. The following observations were made: (1) When the MLC was done between 10 pairs of fully HLA-A,-B,-C, and -D-DR incompatible subjects, a highly significant increase (P less than 0.001) was observed after 2 hr of MLC in all pairs tested. (2) The same increase was observed in all 10 pairs of identical HLA-A,-B, and -C subjects but not sharing HLA-D-DR antigens. (3) In the cases of HLA-D-DR semi-identity, the increase in TEa percentages was less marked after 2 hr of culture (P less than 0.05) and delayed in time to reach the significance level of P less than 0.001 after 4 hr of culture. (4) In contrast, in the case of full HLA-D-DR identity, no increase in TEa percentages was observed at any time in the culture (2, 4, and 24 hr and 4 days) in nine pairs of subjects tested (two pairs of identical twins). In conclusion, these results indicate that the active T rosette MLC is a rapid approach (2 hr) to evaluate HLA-D-DR differences without influence by HLA-A,-B, or -C. As such it is an early marker for HLA-D-DR determination and may become a useful tool in the field of human histocompatibility to study the HLA-D-DR region.

The influence of inosiplex upon various in vitro leucocyte assays was studied in normal individuals. It was found that the drug increases the response of bidirectional and unidirectional mixed lymphocyte cultures at concentrations of 200, 300, and 500 microgram/ml. It also significantly increases the percentage of active T rosettes (concentration range: 50 to 500 microgram/ml) and the percentage of autologous red cell T rosettes (concentration: 100 microgram/ml). In contrast, inosiplex did not modify the percentage of total T rosettes and EAC rosettes. Inosiplex increases the number of nonadherent leucocytes in the leucocyte adherence inhibition test at a concentration range between 100 and 300 microgram/ml. Finally, inosiplex also increases the percentage of monocytes phagocytizing yeast at a concentration between 50 and 500 microgram/ml. These data indicate that inosiplex enhances the function of normal human T cells, monocytes, and possibly neutrophils. Therefore inosiplex appears to have immunostimulant properties.

The interferons are known to induce the expression of cell surface determinants. Gamma interferon, in particular, has been shown to enhance class II antigens (DR) on the cell surface. We used this gamma interferon to induce beta 2-microglobulin (beta 2 mu) and a minor, sex related transplantation antigen called H-Y on the surface of B lymphoma cells. The antitumor effect of interferon could thus be at least twofold: an antiviral effect already known and an increase of intercellular recognition (by cell surface marker enhancement); allowing the tumor cells to be "seen" better by cells of the immune system.

The clinical and cytogenetic findings of a patient with a preleukemic state and trisomy 11 are reported. Trisomy 11 was present as the sole karyotypic alteration at the time of overt leukemia. Trisomy 11 presents an additional chromosomal abnormality not previously described in preleukemia.

Renal transplant recipients receiving low maintenance immunosuppression (azathioprine, 2 mg/kg/day, and prednisolone, 10 mg/day), tolerating their transplants well, and without viral infection disclose a profound depression of NK activity as assessed by 51Cr-release assay. By combining the analysis of the different steps of cytolysis with the agarose single-effector assays and the estimation of circulating large granular lymphocytes (LGL), the defect is shown to be due to a significant decrease of the number of NK cells capable of binding (% target-binding cells 2.0 +/- 0.3 versus 5.7 +/- 0.7 in normals, P less than 0.001) and killing (% cytotoxic target-binding cells 12.4 +/- 1.9 versus 22.0 +/- 0.5 in normals, P less than 0.001) of targets. There is also a significant reduction (P less than 0.001) of both percentages (1.0 +/- 0.2 versus 3.3 +/- 0.4 in normals) and absolute values (9.8 +/- 2.4 versus 62.3 +/- 8.0/microliters in normals) of LGL. These observations indicate that depressed NK activity is due mostly to depletion of NK cells. Functional impairment of NK cells can also be involved. Lack of direct in vitro effects of drugs (6-mercaptopurine, hydrocortisone, and methylprednisolone) at concentrations likely to be reached in vivo during treatments and relative resistance of NK activity after in vivo steroid administration suggest that immunosuppressive drugs act at the precursor cell level or on regulatory mechanisms. Despite functional integrity of two suppressor cell systems of allogeneic NK activity (suppression induced by preculture of lymphocytes with Con A and suppressor granulocytes) in immunosuppressed patients, tested on normal NK cells, NK cells of immunosuppressed patients did not disclose greater susceptibility to Con A-induced suppression. This analysis indicates that the depletion phenomenon is probably a major mechanism in NK depression of patients receiving immunosuppressive drugs.

A fluorometric assay is described for the detection of red blood cell antibodies. The assay reveals as little as 600 molecules of bound, fluoresceinated rabbit anti-human IgG antibodies per erythrocyte. Eleven patients with possible autoimmune erythrocyte disorder and negative direct antiglobulin test were studied by the fluorometric assay. The outcome of the fluorometric assay was compared with that of the human allogeneic rosette test. Results obtained by the two methods were in complete agreement. Five of the patients were shown to possess unexpectedly high levels of erythrocyte-bound IgG in spite of a negative, direct antiglobulin test. These findings and the validity of the fluorometric assay are discussed.