Effect of sera from immunologically altered mice on phytohemagglutinin-induced mouse lymphocyte transformation.

The DNA-synthetic response of mouse spleen cells to phytohemagglutinin in vitro is depressed by the addition of normal mouse serum. The effects of sera from mice that had been modified immunologically were examined. Increased depressive activity was found in sera from nude mice and from mice recently treated with anti-thymocyte globulin, but no change was found in sera from thymectomized, irradiated, bone marrow-reconstituted mice, nor from lethally or sublethally irradiated or cyclophosphamide-treated mice. Base line DNA synthesis was, however, less inhibited by sera from irradiated or cyclophosphamide-treated mice. Increased depressive activity was found in sera from mice with graft-versus-host reaction and from mice injected with Salmonella enteritidis 11RX, in which macrophage stimulation occurred. Increased depressive activity was also found in the sera of mice injected with sheep erythrocytes. T cells do not appear to be a source of depressive activity but B cells, macrophages and nonlymphoid cells may be sources.     

Inhibition of Tobacco Ringspot Virus by the Culture Fluid of L-Lysine-α-Oxidase Producing Strain

Bulletin of Experimental Biology and Medicine - A producing strain of an anti-tumor and antiviral enzyme L-lysine-α-oxidase from Trichoderma was cultured using a technological device of G. K....     

Nylon-fiber-induced neutrophil fragmentation

We have investigated the effects of mechanical elution of neutrophils from nylon-wool fiber (NWF) using the scanning electron microscope and biochemical analysis of elution fractions. We have determined that mechanical removal of neutrophils from nylon-wool fiber disrupts neutrophils adherent to nylon-wool fiber and augments release of granules, release of peripheral cytoplasmic fragments, and release of lactic dehydrogenase, a soluble cytoplasmic enzyme. Mechanical shearing of the adherent cell, and not adherence per se, causes the fragmentation. The extent of fragmentation is proportional to the NWF surface area available to neutrophils and is maximal at the temperature for optimal adherence and spreading. Agents that decrease cell spreading (n-ethylmaleimide and cold) diminish fragmentation. Cytochalasin B, an agent that destabilizes the neutrophil cortex, increases fragmentation. Fragmentation may be an important contributing cause of the abnormal morphology, function, and in vivo survival of nylon-wool-fiber procured human neutrophils. The prevention of fragmentation would appear to be necessary to insure the procurement of optimally functioning cells. Elution of NWF-adherent neutrophils in the cold might be a practical way to diminish neutrophil damage during clinical filtration leukapheresis.     

The effect of biliary enteroenterostomy on the pharmacokinetics of enterally administered cyclosporine in rats

A major factor in poor bioavailability of cyclosporine in children undergoing orthotopic liver transplantation appears to be poor absorption of the drug. Our hypothesis is that the Roux-en-Y choledochojejunostomy used for biliary drainage in these children causes cyclosporine malabsorption by reducing the length of bowel available for absorption and by distally displacing the entry of bile into the intestine. In these experiments, we determined the effect of biliary enteroenterostomy on the pharmacokinetics of enterally administered cyclosporine in Sprague-Dawley rats. Experimental rats (n = 24) were prepared for study by constructing self-emptying jejunal blind loops. Sham rats (n = 9) had jejunal transection and reanastomosis. Control rats (n = 26) had no operation. Two to 4 weeks later, chronic biliary-enteric fistulae were formed in all animals. In experiments, [3H]cyclosporine was delivered into the duodenum while the site of bile delivery varied. Hourly and cumulative [3H]cyclosporine excretion into bile was quantitated, which our preliminary data show to be a valid estimate of absorption. In control rats, bile was delivered into the duodenum or was replaced with saline and sucrose solution. In experimental rats, bile was infused either into the duodenum, which tested bowel shortening only, or into the proximal end of the blind loop, which tested the combined effects of bowel shortening and distal displacement of bile entry. In sham rats, bile was infused into the duodenum, which controlled for previous abdominal surgery, or into the midjejunum, which tested for distal bile entry only. Two effects of biliary enteroenterostomy on cyclosporine absorption were observed.(ABSTRACT TRUNCATED AT 250 WORDS)     

Alloimmunization to platelets in heavily transfused patients with sickle cell disease

Bone marrow transplantation (BMT) is now an option for some patients with sickle cell disease (SCD). Many SCD patients are multiply transfused with red blood cells (RBCs), and may be immunized to alloantigens other than erythrocyte antigens. Because platelet refractoriness is a significant complication during BMT, we wished to determine the prevalence of alloimmunization to platelets in transfused SCD patients. Sera collected from 47 transfused and 14 untransfused SCD patients were screened for HLA and platelet-specific antibodies. Transfusion and RBC antibody histories were reviewed. A subset of the patients were rescreened 1 year later. Eighty-five percent of patients with at least 50 RBC transfusions (22 of 26), 48% of patients with less than 50 transfusions (10 of 21), and none of 14 untransfused patients demonstrated platelet alloimmunization (P < .05). Platelet alloimmunization was more prevalent than RBC alloimmunization (20% to 30%). Half of the platelet reactivity was chloroquine-elutable. Eighteen of 22 patients (82%) on chronic RBC transfusion remained platelet-alloimmunized 11 to 22 months after initial testing. In summary, 85% of heavily transfused SCD patients are alloimmunized to HLA and/or platelet-specific antigens. These patients may be refractory to platelet transfusion, a condition that would increase their risk during BMT. Leukodepletion in the transfusion support of SCD patients should be considered to prevent platelet alloimmunization.     

Immunohistochemical localization of membrane and alpha-granule proteins in human megakaryocytes: application to plastic-embedded bone marrow biopsy specimens

Using a new technique for antigen localization, we have demonstrated platelet proteins in megakaryocytes in plastic-embedded biopsy specimens of normal human bone marrow. In a series of 25 specimens, megakaryocytes showed labeling with antibodies to the integral membrane glycoproteins IIIa, IIb, and the IIb-IIIa complex; granule membrane protein 140; and five alpha-granule matrix proteins: thrombospondin, factor VIII-related antigen, beta-thromboglobulin, platelet factor 4, and fibrinogen. The antibodies to the membrane glycoproteins IIIa, IIb, and IIb-IIIa produced diffuse cytoplasmic staining and heavier staining on the plasma membrane, whereas the antibodies to the alpha-granule matrix proteins produced a distinct granular staining within the cytoplasm. Staining for granule membrane protein 140 was also granular in distribution. Rare mononuclear cells consistent with megakaryocyte precursors were labeled with these markers. Other enzyme histochemical and lectin-binding studies showed that the enzyme alpha-naphthyl acetate esterase, the lectin Ulex europaeus I, and the periodic-acid Schiff reaction were consistent, but not specific, markers of megakaryocytes. This immunohistochemical technique should facilitate the examination of qualitative and quantitative changes in megakaryocytes in a variety of physiologic and pathologic processes.