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Natural Killer Cytotoxicity In a prospective study of colorectal cancer patients, the number of natural killer cells increased significantly in both transfused and untransfused patients who had potentially curative surgery (8). Natural killer cytotoxicity declined significantly in untransfused patients while increasing slightly in the transfused. Three months following surgery no differences in peripheral cell numbers or T cell subsets between the transfused and untransfused patients were noted. Removing leukocytes from the blood to be transfused abrogates the changes in natural killer cytotoxicity (9) These studies conflict with the findings of a prospective study of colorectal cancer (9). Patients were randomized to receive whole blood or filtered whole blood, removing 99.98% of the leukocytes and platelets. Natural killer cytotoxicity declined significantly in patients receiving unfiltered whole blood and remained significantly depressed 30 days following surgery. Natural killer cytotoxicity in untransfused patients and in patients receiving filtered blood declined significantly with surgery but fully recovered by 30 days. Since declines in natural killer cytotoxicity can be prevented in cancer patients by simply filtering blood and since natural killer cytotoxicity is of proven prognostic significance, filtered blood may improve the outcome for patients with malignancies. Immune Function Following Transfusion of Dialysis Patients The effect of transfusion on dialysis patients is both immune enhancing and immune suppressing. Transfusion is followed by the appearance of antibodies to antigens present on the cells of the transfused blood and these antibodies are capable of killing lymphocytes having these antigens. Lymphocytotoxic antibodies are responsible for early graft failures and their appearance is called sensitization. Immune suppression accompanies sensitization. Suppressor lymphocytes begin to appear in the serum of transfusion recipients at the same time lymphocytotoxic antibodies are appearing and their appearance is probably also mediated by antibodies -antibodies which play a role in regulating immune function. Suppresser cells suppress lymphocyte responses to antigens on the cells of transfused blood and on the cells of the transplant. Lymphocyte suppression following blood transfusion may be permanent or transient, but in most recipients the degree of suppression is enhanced by additional blood transfusions and probably maintained by the presence of the allograft following transplant. In dialysis patients who receive blood transfusions lymphocyte responses to antigens, mitogens and homologous lymphocytes decline to 50% one week following a single unit of blood in comparison to lymphocyte reactivity measured immediately before transfusion (10). Lymphocyte reactivity declines progressively with additional units of blood given and returns to pretransfusions levels if blood is withheld for six weeks. Suppresser activity is enhanced following transfusion but not at one week when lymphocyte reactivity is at its lowest point, indicating that suppressive activity and lymphocyte inhibition are separate events (11). Finally, natural killer cytotoxicity is significantly reduced following transfusion of dialysis patients and remains low following transplant, although a correlation between natural killer cytotoxicity and graft survival has not been shown (12).
DOI link for Natural Killer Cytotoxicity In a prospective study of colorectal cancer patients, the number of natural killer cells increased significantly in both transfused and untransfused patients who had potentially curative surgery (8). Natural killer cytotoxicity declined significantly in untransfused patients while increasing slightly in the transfused. Three months following surgery no differences in peripheral cell numbers or T cell subsets between the transfused and untransfused patients were noted. Removing leukocytes from the blood to be transfused abrogates the changes in natural killer cytotoxicity (9) These studies conflict with the findings of a prospective study of colorectal cancer (9). Patients were randomized to receive whole blood or filtered whole blood, removing 99.98% of the leukocytes and platelets. Natural killer cytotoxicity declined significantly in patients receiving unfiltered whole blood and remained significantly depressed 30 days following surgery. Natural killer cytotoxicity in untransfused patients and in patients receiving filtered blood declined significantly with surgery but fully recovered by 30 days. Since declines in natural killer cytotoxicity can be prevented in cancer patients by simply filtering blood and since natural killer cytotoxicity is of proven prognostic significance, filtered blood may improve the outcome for patients with malignancies. Immune Function Following Transfusion of Dialysis Patients The effect of transfusion on dialysis patients is both immune enhancing and immune suppressing. Transfusion is followed by the appearance of antibodies to antigens present on the cells of the transfused blood and these antibodies are capable of killing lymphocytes having these antigens. Lymphocytotoxic antibodies are responsible for early graft failures and their appearance is called sensitization. Immune suppression accompanies sensitization. Suppressor lymphocytes begin to appear in the serum of transfusion recipients at the same time lymphocytotoxic antibodies are appearing and their appearance is probably also mediated by antibodies -antibodies which play a role in regulating immune function. Suppresser cells suppress lymphocyte responses to antigens on the cells of transfused blood and on the cells of the transplant. Lymphocyte suppression following blood transfusion may be permanent or transient, but in most recipients the degree of suppression is enhanced by additional blood transfusions and probably maintained by the presence of the allograft following transplant. In dialysis patients who receive blood transfusions lymphocyte responses to antigens, mitogens and homologous lymphocytes decline to 50% one week following a single unit of blood in comparison to lymphocyte reactivity measured immediately before transfusion (10). Lymphocyte reactivity declines progressively with additional units of blood given and returns to pretransfusions levels if blood is withheld for six weeks. Suppresser activity is enhanced following transfusion but not at one week when lymphocyte reactivity is at its lowest point, indicating that suppressive activity and lymphocyte inhibition are separate events (11). Finally, natural killer cytotoxicity is significantly reduced following transfusion of dialysis patients and remains low following transplant, although a correlation between natural killer cytotoxicity and graft survival has not been shown (12).
Natural Killer Cytotoxicity In a prospective study of colorectal cancer patients, the number of natural killer cells increased significantly in both transfused and untransfused patients who had potentially curative surgery (8). Natural killer cytotoxicity declined significantly in untransfused patients while increasing slightly in the transfused. Three months following surgery no differences in peripheral cell numbers or T cell subsets between the transfused and untransfused patients were noted. Removing leukocytes from the blood to be transfused abrogates the changes in natural killer cytotoxicity (9) These studies conflict with the findings of a prospective study of colorectal cancer (9). Patients were randomized to receive whole blood or filtered whole blood, removing 99.98% of the leukocytes and platelets. Natural killer cytotoxicity declined significantly in patients receiving unfiltered whole blood and remained significantly depressed 30 days following surgery. Natural killer cytotoxicity in untransfused patients and in patients receiving filtered blood declined significantly with surgery but fully recovered by 30 days. Since declines in natural killer cytotoxicity can be prevented in cancer patients by simply filtering blood and since natural killer cytotoxicity is of proven prognostic significance, filtered blood may improve the outcome for patients with malignancies. Immune Function Following Transfusion of Dialysis Patients The effect of transfusion on dialysis patients is both immune enhancing and immune suppressing. Transfusion is followed by the appearance of antibodies to antigens present on the cells of the transfused blood and these antibodies are capable of killing lymphocytes having these antigens. Lymphocytotoxic antibodies are responsible for early graft failures and their appearance is called sensitization. Immune suppression accompanies sensitization. Suppressor lymphocytes begin to appear in the serum of transfusion recipients at the same time lymphocytotoxic antibodies are appearing and their appearance is probably also mediated by antibodies -antibodies which play a role in regulating immune function. Suppresser cells suppress lymphocyte responses to antigens on the cells of transfused blood and on the cells of the transplant. Lymphocyte suppression following blood transfusion may be permanent or transient, but in most recipients the degree of suppression is enhanced by additional blood transfusions and probably maintained by the presence of the allograft following transplant. In dialysis patients who receive blood transfusions lymphocyte responses to antigens, mitogens and homologous lymphocytes decline to 50% one week following a single unit of blood in comparison to lymphocyte reactivity measured immediately before transfusion (10). Lymphocyte reactivity declines progressively with additional units of blood given and returns to pretransfusions levels if blood is withheld for six weeks. Suppresser activity is enhanced following transfusion but not at one week when lymphocyte reactivity is at its lowest point, indicating that suppressive activity and lymphocyte inhibition are separate events (11). Finally, natural killer cytotoxicity is significantly reduced following transfusion of dialysis patients and remains low following transplant, although a correlation between natural killer cytotoxicity and graft survival has not been shown (12).
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