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N Blumberg

Publications and source records attributed to N Blumberg.

At least 55 records · Page 3Linked to original sources
PubMed1994

Effects of transfusion on immune function. Cancer recurrence and infection.

The paradigm related to the immunologic consequences of allogeneic blood transfusions has been extended from humoral allosensitization to the effects of transfusion on cellular immune function. This includes downregulation of effector cells, activation of latent viral infection, and the prolonged circulation of donor immunocompetent cells, as seen in graft-vs-host disease. There are now extensive data showing conclusively that allogeneic transfusions are associated with increases in cancer recurrence rates (80% in colorectal cancer) and postoperative bacterial infections (as much as 200% to 1000% in some studies). Whether these associations are causal or not remains in doubt. Based on animal and clinical studies, we believe these associations are likely, in part, due to immune dysregulation caused by transfusion, perhaps augmented by the effects of hemorrhage, anesthesia, and surgical stress. The most likely mechanism underlying transfusion-induced immunosuppression is anergy due to presentation of large amounts of antigen through the intravenous route. This favors presentation of antigen by "nonprofessional" antigen-presenting cells, a situation that usually leads to anergy or tolerance rather than immune activation. Two additional hypothetical mechanisms proposed for immune dysregulation after allogeneic transfusion are (1) prolonged circulation of donor cells causing subclinical graft-vs-host disease, and (2) reactivation of immunosuppressive viruses latently present in recipient white blood cells. Results of some initial interventional studies, employing autologous transfusions or removing white blood cells from allogenic donor blood suggest that relatively simple, cost-effective strategies to ameliorate these complications may be at hand.

Bacterial Infections↗
PubMed1993

ABO and platelet transfusion revisited.

Historically, ABO compatibility between donor and recipient has been considered of minor importance for platelet transfusion. However, in a recent randomized trial we showed that provision of only ABO-identical platelets was associated with a significantly higher corrected count increment (CCI) in the early transfusions and with a twofold reduction in refractoriness, as compared with platelets given unmatched for ABO. In older studies this phenomenon was not observed. We wondered whether in these previous studies the use of the conventional term "ABO compatible", whereby ABO-identical platelet transfusions are grouped with those that are merely ABO compatible, might have obscured the advantages of the ABO-identical platelets. In this paper the CCI from our original study are compared with what would have been found had the conventional terminology of "ABO compatible" and "ABO incompatible" been used. In our original study the mean CCI in patients receiving only ABO-identical platelets was 64% higher than that achieved with ABO-unmatched products. However, when the transfusions were reanalyzed according to conventional terminology of ABO "compatible" and "incompatible," the actual benefits of ABO-identical platelets were no longer detected. Thus, had we used the conventional terminology in the original study we would have come to completely different conclusions about the importance of ABO in platelet transfusion. We hypothesize that transfusion of ABO-incompatible plasma leads to the formation of immune complexes that can destroy compatible platelets by indirect mechanisms. This model predicts that the success of a transfusion could be affected by previous incompatible transfusions. When transfusions were classified as to whether they were first, second, or third unmatched transfusion, increasing numbers of transfusions of ABO-incompatible plasma were associated with progressively poorer mean increments. The same was true for platelet ABO-incompatible transfusions. In contrast, increasing numbers of ABO-identical transfusions were not associated with poorer increments. The failure to appreciate that (a) transfusions containing ABO-incompatible plasma yield poor increments and (b) the effects of ABO-nonidentical transfusions are cumulative, and therefore affect the success of subsequent identical transfusions, may have led in the past to the incorrect conclusion that ABO matching was of minor importance in repetitively transfused patients.

ABO Blood-Group System↗
PubMed1993

Circulating immune complexes involving the ABO system after platelet transfusion.

It has been proposed that when ABO unmatched platelets are transfused circulating immune complexes (CIC) may be formed between the patient's soluble ABH antigens and the transfused antibodies. Platelets might then be destroyed by bystander mechanisms or by the binding of CIC to the Fc receptor or to C3 binding membrane proteins on the platelet. An ELISA C1q assay was used to detect CIC in 40 patients with haematological diseases who had received multiple platelet transfusions. A significantly larger number of refractory patients were positive (41%) in the assay than non-refractory patients (13%) or normal blood donors (0%). The presence of circulating IgG anti-A was sought in six group A refractory patients who had been transfused with ABO unmatched platelets. To determine whether the IgG anti-A was monomeric or in high molecular weight complexes, the serum was fractionated by gel exclusion chromatography and fractions were tested for the presence of IgG anti-A. In all six patients the peak of IgG anti-A binding occurred in fractions of high molecular weight (200-900 kD). Five out of six patients also demonstrated anti-A activity in fractions corresponding to monomeric IgG (about 150-180 kD). Fractions containing high molecular weight anti-A were purified using a protein G column and the eluates were tested for the presence of group A antigen using dot immunoblotting. Group A antigen was associated with the purified IgG anti-A in 4/5 patients tested. Appropriate transfused and non-transfused controls had no anti-A in any fractions. Although not unexpected, these studies demonstrate for the first time that refractory patients receiving ABO unmatched platelets have CIC composed of ABO antigens and their corresponding antibodies present in their serum that circulate for at least several days. It also confirms the hypothesis that some CIC in haematological patients are induced by transfusion.

ABO Blood-Group System↗
PubMed1993

The role of ABO matching in platelet transfusion.

A prospective controlled trial was performed to determine whether the use of ABO-identical platelets from the start of treatment might provide higher post-transfusion platelet increments, reduce the number of platelet transfusions and ultimately delay the onset of refractoriness. Forty newly diagnosed patients with haematological diseases were randomized to receive either pooled ABO-identical platelets or pooled platelets unmatched for ABO group throughout their course. The corrected platelet count increments (CCI) were calculated for the first 25 transfusions of each patient and non-immune factors present at the time of each platelet transfusion were documented. The mean CCI for the first 25 transfusions in the ABO-identical group was significantly higher (6600 +/- 7900 SD) than that achieved with ABO unmatched platelets (5200 +/- 7900; p < 0.01). The effect was most marked for the first 10 transfusions for each patient where the CCI was 64% higher in the ABO-identical group (8200 +/- 7500 vs 5000 +/- 8100; p < 0.0002). Patients given ABO-identical platelets required only about half as many transfusions in the first 30 days (10 versus 17, p < 0.05) or during the first admission (11 versus 21 p < 0.01) as patients in the ABO-unmatched group. A smaller percentage of patients in the ABO-identical group became refractory (36% vs 75% p < 0.03). The data suggest that patients requiring long-term platelet support should be transfused with ABO-identical platelets.

ABO Blood-Group System↗
PubMed1992

Malignant melanoma: primary presentation in bone marrow and lymph node.

We describe an unusual presentation of malignant melanoma with simultaneous lymph node and bone marrow metastasis. In addition the disease was associated with immune-mediated thrombocytopenia. A brief remission was obtained with combination chemotherapy.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1992

Antibodies to plasma proteins: an association with platelet transfusion refractoriness.

We hypothesized that antibodies to HLA-linked polymorphic plasma proteins could be involved in platelet refractoriness by an 'innocent bystander' or immune complex mechanism. Employing a kinetic enzyme-linked immunosorbent assay (ELISA) technique the ability of IgG from the plasma of refractory patients to bind to albumin, fibrinogen, complement components C2 and C4 was measured. As compared with controls a high percentage of refractory patients had increased IgG capable of binding to all four plasma proteins: C2 (83%), C4 (83%), albumin (75%), fibrinogen (34%). In the presence of exogenous plasma proteins these antibodies mediated increased deposition of IgG onto normal donor platelets. The plasma protein binding IgG consisted both of monomeric IgG and a broad range of high molecular weight complexes. IgG anti-plasma protein antibody could be eluted from platelets of refractory patients. The development of anti-plasma protein IgG was studied during the course of platelet transfusion therapy and found to increase progressively so that by the 20th transfusion greater than 90% of samples were positive. The presence of plasma protein binding activity correlated with the development of increased levels of platelet bound IgG and refractoriness. Multiple platelet transfusions lead to sensitization to polymorphic determinants on C2 and C4 as well as the formation of high molecular weight complexes. These antibodies and complexes contribute to the deposition of IgG on platelets and may contribute to refractoriness.

Albumins↗
PubMed1992

Homologous blood transfusion as a risk factor for postoperative infection after coronary artery bypass graft operations.

Homologous transfusions are immunosuppressive and associated with a higher risk of postoperative infection. In this retrospective analysis, we studied 238 consecutive patients who underwent first-time coronary operations by a single surgeon in 1988 to 1989 and collected clinical and laboratory data relevant to postoperative infections including pulmonary, urinary, and wound sites. Culture-proved postoperative infections occurred in 16 of the 238 patients (6.7%), with only 3 (1.3%) being deep sternal wound infections. Seven of 16 (44%) of the infections were away from the wound sites, suggesting that nonsurgical variables contributed to at least some infections. Factors significantly associated with an increased risk of postoperative infection by univariate analysis included female sex, diabetes mellitus, and transfusion dose. Infections occurred in 3.9% of patients receiving up to 2 units of red cells and whole blood, 6.9% receiving 3 to 5 units, and 22% of those receiving 6 units or more. Multiple linear and logistic regression analysis showed that transfusion dose was the most significant predictor of infection, days of fever, days of antibiotic therapy, and length of hospital stay. Homologous transfusion is associated (in a dose-dependent fashion) with a threefold to eightfold increased risk of postoperative infection in patients undergoing coronary artery operations. This increased risk of infection may be due to transfusion-induced immunosuppression of the patient.

Aged↗
PubMed1991

Severe fetal hydrops resulting from ABO incompatibility.

Severe fetal hydrops was diagnosed at 34 weeks' gestation. Funipuncture revealed a normal 46,XX karyotype and a hematocrit of 20%. Cesarean delivery was performed. Neonatal blood testing showed blood type B positive, positive direct and indirect Coombs, and an anti-B antibody titer of 1:64. The maternal blood group was O positive with a titer of 1:65,536 immunoglobulin G (IgG) anti-B antibody (after inactivation of IgM anti-B antibody). This report documents a rare case of fetal hydrops resulting from ABO incompatibility with neonatal survival.

ABO Blood-Group System↗
PubMed1990

Transfusion-induced immunomodulation and its clinical consequences.

The bulk of experimental and clinical data support the theory that homologous transfusion causes significant down-regulation of immunologic functions in a number of settings. These changes in immune function may account for the beneficial associations of transfusion with increased renal allograft survival, and decreased recurrence in Crohn's disease. Conversely, these transfusion-induced effects may be responsible in part for the deleterious association of homologous transfusion with increased cancer recurrence, and increased posttransfusion bacterial and viral infection rates. Host defenses against malignancy and infection may in some instances be severely compromised by transfusions of homologous blood, but the circumstances under which this occurs need to be better defined. Likewise, the hypothesis that modification of blood components to contain fewer leukocytes or less plasma might ameliorate these effects is attractive, but little or no data exist to support or refute it. Future clinical studies will no doubt address these issues.

Blood Transfusion↗
PubMed1990

The relationship of blood transfusion, tumor staging, and cancer recurrence.

Previous research demonstrated a relationship between transfusions of whole blood, or large numbers of red cell concentrates, and later recurrence of cancers of the colon, rectum, cervix, and prostate. It is possible that the transfusion of whole blood may represent a surrogate marker for advanced or more aggressive clinical disease. The relationship of clinical or histologic tumor stage, blood transfusion status, and disease outcome was studied in detail. Patients receiving no transfusions or small numbers of red cells (less than or equal to 3 units) had uniformly better recurrence and survival experiences than patients receiving similar amounts of blood that included at least 1 unit of whole blood, regardless of the patient's clinical or histologic tumor stage. In multivariate analyses, stage was an independent predictor of outcome, and transfusion status was not a surrogate marker for stage. The effects on recurrence of stage and transfusion appear to be cumulative. These results are consistent with but do not prove the hypothesis that the transfusion of large amounts of stored plasma and cellular debris impairs the host defenses against cancer, regardless of the underlying biologic and clinical aggressiveness of the cancer.

Blood Transfusion↗
PubMed1990

Association of transfusion with postoperative bacterial infection.

Homologous blood transfusion has been implicated as a modulator of the host immune system in a number of clinical settings. Improved renal allograft survival is observed in patients receiving pretransplant transfusions. Decreased recurrence of active inflammatory bowel disease has been recently reported in transfused patients with Crohn's disease. Conversely, deleterious immunomodulatory effects of transfusion may explain the association between transfusion and increased susceptibility to cancer recurrence and bacterial and viral infection. Clinical studies regarding cancer recurrence and transfusion are retrospective and conflicting. There is epidemiologic evidence for more rapid progression of HIV-1 infection in heavily transfused patients. Studies on transfused surgical patients have shown transfusion to be associated with an increased frequency of postoperative bacterial infections. Some studies have come to different conclusions. These investigators have suggested that transfusion may represent a surrogate marker for other risk factors for infection. Animal models designed to control for confounding factors have supported an association between transfusion and bacterial infection severity in most, but not all, reports. Attempts to define the immunologic alterations associated with transfusion have revealed a generalized impairment of cellular immunity in both humans and animals. Although the preponderance of data supports an association between perioperative transfusion and increased susceptibility to postoperative bacterial infection, it is not certain to what extent this relationship constitutes cause and effect.

Animals↗
PubMed1989

The fine specificity of Lewis blood group antibodies. Evidence for maturation of the immune response.

Eight human Lewis blood group antibodies were characterized for their fine specificity by the use of specific immunoadsorbents and a kinetic enzyme-linked immunosorbent assay technique. Examination of sera following immunoglobulin fractionation showed IgM anti-Le(a) exhibiting broad cross-reactivity with structures biochemically related to the Lewis antigens. IgG anti-Le(a) binding was restricted to Le(a) and Le(b) These findings are consistent with the concept of affinity maturation of the immune response, which has been previously demonstrated only in animal model systems.

Antibody Specificity↗
PubMed1989

Transfusion and recipient immune function.

For some time it has been known that allogeneic blood transfusions have immunologic effects on animal and human recipients. These effects include increased numbers of suppressor T cells, decreased natural killer-cell function, decreased function of macrophages and monocytes, induction of anti-idiotypic antibodies that suppress allogeneic antigen recognition, and decreases in alloreactivity of mononuclear cells in mixed lymphocyte cultures. The meaning of these changes is not clearly understood, nor is the exact clinical importance of these alterations known. However, these decreases in immunologic function may explain a number of clinical consequences some investigators believe are the sequelae of homologous blood transfusions. Clinically important outcomes that are associated with transfusions are improved survival of renal allografts and increased risks of bacterial infection and cancer recurrence after perioperative transfusions. Transfusion of plasma-rich blood components (eg, whole blood) has been specifically associated with earlier cancer recurrence and better renal allograft survival in some patient groups. The new hypothesis that transfusion of stored plasma is a major factor in altering host immune defenses is supported by the observation that patients infected with human immunodeficiency acquired immunodeficiency syndrome more rapidly if they have been transfused with large amounts of plasma. Contrary to previous belief, the transfusion of homologous stored blood plasma may have as great or greater effects on immunity than transfusion of white blood cells. We believe investigation into the immunologic effects of transfusions is likely to have a significant impact on transfusion medicine research and practice over the coming years.

Acquired Immunodeficiency Syndrome↗