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W H Dzik

Publications and source records attributed to W H Dzik.

71 records · Page 4Linked to original sources

Mononuclear cell-surface antigens during storage of banked blood.

The surface antigens present on lymphocyte subpopulations and monocytes in whole blood stored under standard blood bank conditions were analyzed with a series of monoclonal antibodies and a fluorescence-activated cell sorter. During the first week of storage, the percentage of viable cells bearing T lymphocyte markers declined from 66% to 29% (P less than 0.001). Within the T cell subset, there was a disproportionate decrease in the percentage of cells reacting with anti-Leu 3a (a helper T cell marker) resulting in a reduction in the measured ratio of helper-to-suppressor T cells (P less than 0.01). The relative percentage of cells bearing B lymphocyte markers increased from 11% to 31% (P less than 0.001). The proportion of HLA-DR-positive cells that were B cells increased during the first week of storage from 38% to 65% (P less than 0.01). The degree of residual antigen expression as measured by the remaining median intensity of fluorescence was significantly greater for B cell and HLA-DR antigens as compared with T cell antigens. The measured changes during storage in the relative proportions of mononuclear cells expressing cell-surface antigens probably result from a combination of differential residual antigen expression and differential survival of mononuclear subpopulations. The presence of adenine in the anticoagulant-preservative solution had no measurable effect. Storage at 4 C, however, was shown to result in a 70% decrease in the proportion of antigen-bearing T cells, even as early as 24 hr of storage. The findings may have bearing on the beneficial effect of blood transfusion in renal transplant recipients, as well as on experimental models of the immune response to transfusion.

Adenine↗

Hepatitis B viral infection: Part II. Public health aspects.

It is estimated that 200 million people worldwide, including 0.1 percent of the U.S. populations, are carriers of hepatitis B virus. The carrier state is defined as positivity for hepatitis B surface antigen for six or more months without additional features of acute or chronic infection. The risk of spreading hepatitis B virus depends on the infectivity of the carrier, the nature of exposure to the carrier and the susceptibility of the contact. At present, some types of exposure merit prophylaxis with immune globulin. A safe and effective vaccine is currently available and should markedly reduce the incidence of hepatitis B and its chronic sequelae.

Adult↗

Hepatitis B viral infection: part I. Clinical features.

As a result of early basic biomedical research, the hepatitis B virus has become the best understood cause of viral liver infection in man. The virus has a unique antigenic structure and elicits specific antibody responses. A proper understanding of the serologic events during infection is essential for accurate diagnosis and management. Only 50 percent of infected individuals manifest clinical signs of disease, but 5 to 10 percent develop either a chronic asymptomatic antigen carrier state or chronic hepatitis. Some patients progress to cirrhosis and possibly to primary hepatocellular carcinoma.

Alanine Transaminase↗

Accelerated destruction of radiolabeled red cells due to anti-Coltonb.

A patient who developed anti-Cob in response to transfusion was studied. The antibody was a warm-reactive, high-titered, IgG alloantibody that did not fix complement, and reacted strongly in the antiglobulin phase. During a period of transfusion the patient developed a positive direct immunoglobulin test with anti-Cob recoverable in the eluate. Reactions were stronger with enzyme-treated red cells. Survival studies with 51Chromium-labeled red cells showed: 1) normal survival of Co(b-) red cells, and 2) accelerated destruction of Co(b+) red cells; initially, cells were destroyed with a one-half disappearance time of 4 days, but after about 4 days, the rate of destruction increased. This study, together with reported suspected transfusion reactions attributed to anti-Cob, suggest that anti-Cob should be considered a clinically significant antibody.

Aged↗

ABO and Lewis blood group antigens of donor origin in the bile of patients after liver transplantation.

The authors prospectively studied the expression of blood group antigens and their corresponding glycosyltransferases in the bile of 11 patients who received orthotopic liver transplants. In six patients, the donor was of the same ABO/Lewis/secretor as the recipient, and the expected blood group antigens were found in the postoperative bile. Five patients who received transplants from donors discordant for either ABO, Lewis, or secretor status continued to produce blood group antigens of donor origin. This study provides evidence that the expression of soluble blood group antigens is under autonomous end-organ control.

ABO Blood-Group System↗

Preparation of white cell-reduced platelet concentrates from whole blood during component preparation.

This article introduces a new method of component preparation that is capable of producing white cell (WBC)-reduced platelet concentrates (PCs) from whole blood. Whole blood is separated into packed red cells (RBCs) and platelet-rich plasma (PRP) by centrifugation, and the PRP is expressed through a newly designed WBC removal filter into the platelet storage bag. The filtered PRP is then centrifuged and yields WBC-reduced PCs and plasma for freezing as fresh-frozen plasma (FFP). The method uses standard triple-pack blood bags and centrifugation protocols. Fifteen WBC-reduced PCs prepared with this technique had an average volume of 56.7 mL, an average Day 5 platelet content of 8.6 x 10(10) per unit, and an average Day 5 WBC content of 0.83 +/- 0.7 x 10(4) per unit (0.14 WBCs/microL). This represents WBC removal equal to at least 99.9 percent (3 log10) of the WBCs found in standard PCs prepared in our laboratory by an identical centrifugation protocol. Paired studies documented a 4.5-percent platelet loss by filtration. Filtration had no effect on the plasma prepared for FFP as measured by prothrombin time; activated partial thromboplastin time; factors I, V, VIII:C, and VIII:von Willebrand factor; antithrombin-III; albumin; globulin; or total protein. This method holds promise as a simple and highly effective technique for the production of WBC-reduced PCs by filtration during component preparation.

Blood Platelets↗

Leukopoor platelet concentrates: a direct comparison of three blood filters.

Repeated exposure to foreign human leukocyte antigens (HLA) present on both platelets and leukocytes often results in refractoriness to transfusions of platelet concentrates. Evidence now exists which suggests that the leukocytes are more immunogenic and that their removal from blood products may delay or prevent the development of refractoriness. In this study, the ability of three blood filters to remove leukocytes from platelet concentrates was directly compared. Pooled platelet concentrates were filtered through the Fenwal 4C 2131 depth microaggregate blood filter (MABF), the Pall Ultipor SQ 40S screen MABF, and the Terumo Imugaard IG-500 blood filter. The results were then compared to a previous study (done in the same laboratory) which used differential centrifugation to render platelet concentrates leukocyte-poor. The Fenwal and Pall MABFs did not remove leukocytes or platelets from platelet concentrates. In contrast, the Terumo filter removed 90.2 percent of the leukocytes while sacrificing 7.5 percent of the platelets; results superior to differential centrifugation which removed 84.9 percent of the leukocytes but sacrificed many more platelets, 32.3 percent. The Terumo Imugaard IG-500 blood filter produces leukocyte-poor platelet concentrates as efficiently as differential centrifugation with much less platelet loss. Use of the Terumo filter may aid further studies required to evaluate the use of leukocyte-poor platelet concentrates for the prevention of platelet refractoriness.

Blood Platelets↗