Functional capabilities of steroid-recruited neutrophils harvested for clinical transfusion

Granulocyte Transfusion: Current Status

Infection associated with therapy-related neutropenia continues to be a major cause of morbidity and mortality. Renewed interest in granulocyte transfusion therapy as treatment for this condition has been generated by the observation that large doses of granulocytes can be obtained from donors who have been stimulated with granulocyte colony-stimulating factor (G-CSF). Granulocytes collected from these donors have been shown to effectively raise the patient's neutrophil count and appear to function normally as judged both by in vitro and in vivo measures. The evidence for clinical efficacy is limited to that of case reports and small series, and the results are not uniform. Randomized controlled clinical trials are needed to determine whether this therapy is useful in either clearing infections or prolonging survival.

Glucocorticosteroids as immunosuppressive agents

When administered at pharmacological dosages, glucocorticosteroid hormones alter leukocyte kinetics, phagocytic cell function, cell-mediated immunity, and, to a lesser extent, humoral immunity. These properties are used to advantage in the treatment of immunologically mediated disease. Corticosteroids are used to suppress pathological immune responses associated with autoimmunity, inhibit rejection of allogenic tissues after organ transplantation, and to diminish inflammation associated with a wide variety of hypersensitivity disorders. The mechanisms by which corticosteroids relieve these conditions are still not completely understood but have recently become more comprehensible. By understanding how corticosteroids exert their effects, we can make better clinical decisions in the management of immune-mediated disease.

Blood center perspective of granulocyte transfusions: future applications

The role of the blood bank in provision of an optimal granulocyte concentrate is discussed. The importance of the granulocyte dose is emphasized, and recent developments permitting the collection of larger numbers of cells are reviewed. In particular, the administration of granulocyte colony-stimulating factor to normal donors has been reported to result in dramatically increased neutrophil yields. Recent data has also suggested that increased efficiencies of collection can be realized by the use of hetastarch as the red cell sedimenting agent.

Effects of in vitro adrenocorticotrophic hormone, cortisol and human recombinant interleukin-2 on porcine neutrophil migration and luminol-dependent chemiluminescence

Experiments were performed on isolated neutrophils tested in vitro to investigate the role of adrenocorticotrophic hormone (ACTH), cortisol and recombinant human interleukin-2 (rhIL-2) in modulating porcine polymorphonuclear (PMN) leukocyte function. Elevated levels of cortisol, similar to that observed during stressful experiences, caused a decrease in PMN chemokinesis (P < 0.02), chemotaxis (P < 0.001) and luminol-dependent chemiluminescence. ACTH at concentrations reflective of high stress conditions reduced PMN chemotaxis (P < 0.02) and chemokinesis (P < 0.01). In vitro rhIL-2 reversed (P < 0.05) the cortisol-induced and ACTH-induced suppression of PMN chemokinesis. These data indicate that specific neutrophil functions in pigs may be impaired by stress-related hormones of the pituitary-adrenal axis and that IL-2 may reverse some endocrine-induced suppression in chemokinesis.

The influence of corticosteroids on host defense mechanisms

Glucocorticosteroid hormones affect virtually every tissue type in the body, including tissues of host-defense systems. There is an enormous body of literature concerning specific effects of corticosteroids on host defenses. This literature review examines the affects of corticosteroids on leukocyte kinetics, phagocytic immunity, cell-mediated immunity, and humoral immunity in steroid-resistant species.

Granulocyte transfusions in neutropenic patients

Patients with severe neutropenia are at increased risk for systemic infection with bacteria or fungi. This risk is in proportion to both the degree and duration of the neutropenic process. Although granulocyte transfusion as a means of augmenting host defenses would appear to be a logical therapeutic intervention in clinical contexts involving severe and prolonged neutropenia, several features of granulocyte physiology and collection complicate such considerations. These include the large numbers of granulocytes normally produced by healthy hosts, the short survival of the granulocyte in the circulation after transfusion, the relatively small number of granulocytes which can be collected using currently available pheresis techniques, problems associated with alloimmunization, and the possibility of transferring disease (CMV, toxoplasmosis, hepatitis) by means of these transfusions. In the mid-1970s, well-designed clinical studies strongly suggested that patients with documented Gram-negative sepsis or tissue infection that failed to respond to appropriate antibiotics were significantly benefited by granulocyte transfusions. With recent advances in potent, broad-spectrum antibiotic availability, some have questioned whether these observations remain valid. Several studies regarding the prophylactic use of granulocyte transfusions in patients undergoing allogeneic bone marrow transplantation and/or induction therapy for leukemia have failed to reveal therapeutic benefits and suggested the possibility of significant side effects. These studies are reviewed.

Lysostaphin-based assay of human granulocyte functions: a reevaluation

Lysostaphin, a staphylococcus-derived staphylocidal substance, has widely been used in assays of granulocyte phagocytic and bactericidal capability. It rapidly kills extracellular bacteria. Thus, a separate determination of intracellular surviving bacteria can be performed. One prerequisite for this approach is the safe inactivation of lysostaphin (usually brought about by trypsin) before the intracellular bacteria are externalized for plating. This inactivation has been found by others to be incomplete. Data are presented demonstrating a safe inactivation of lysostaphin by trypsin, if the pH value is maintained within the alkaline range. A low variation of results is obtained by plotting the total number of bacteria killed per incubate vs the logarithm of initial bacterial inoculum or of the intracellular surviving bacteria, leading to linear regression lines. The variation of the results increases greatly for initial bacteria/granulocyte proportions of greater than 5/1. The results obtained for two different St. aureus strains are significantly different. Dexamethasone pretreatment (12 mg p.o. within 8 h) had no detectable influence, when fresh blood was assayed, while blood storage at room temperature for 12 h (without dexamethasone pretreatment) led to a significant functional impairment, mainly of bactericidal capability when analyzed in a pairwise fashion. A major limitation of this kind of assays is that killed bacteria cannot be determined directly.

Human polymorphonuclear leukocytes of the bone marrow, circulation, and marginated pool: function and granule protein content

Polymorphonuclear leukocytes (PMN) demonstrate altered function during acute infections and after administration of corticosteroids. We questioned whether or not such changes are due to population shifts from functionally different compartments of the granulocyte pool. Volunteers were given epinephrine to induce demargination or hydrocortisone (HC) to promote egress of PMN from the bone marrow. PMN obtained before and after drug administration were compared for adherence, chemotaxis, luminol-enhanced chemiluminescence, and total content and release of lactoferrin (LF), myeloperoxidase (MPO), and beta-glucuronidase (beta-glu). Epinephrine induced a significant neutrophilia of mature PMN (segmented neutrophils), but there were no changes in function or granule protein content. HC induced a significant neutrophilia with segmented neutrophils and immature PMN (bands). Circulating PMN obtained 4 hr after HC administration demonstrated less adherence, increased chemiluminescence, increased MPO release, and decreased MPO content. Band neutrophils, however, were more adherent than segmented PMN and showed a similar decrease in adherence following HC in vivo. Thus alteration of PMN adherence following intravenous corticosteroids is not due to an influx of immature neutrophils. On the other hand, it is possible that MPO content and release and capacity for oxidative metabolism change as PMN mature.

Granulocyte transfusion therapy

Granulocyte transfusion therapy has been used as an adjunct to broad spectrum antibiotics in the management of serious infections in granulocytopenic patients. This treatment is based upon the observation that the incidence of infection is inversely related to the absolute granulocyte count in granulocytopenic patients and upon the demonstrated value of replacement therapy of other blood cell components such as platelets for thrombocytopenia. In addition, the occurrence of dramatic clinical improvement frequently noted with only small increases in granulocyte count as the marrow begins to regenerate suggests that transfusions of granulocytes should be of benefit.

The function and structure of granulocytes collected using the IBM 2997 separator

The effect of oral methylprednisolone and the sedimenting agent, hydroxyethyl starch, on granulocyte recovery, morphology, and function was studied in a volunteer donor programme. Using the IBM 2997, 10 litres of whole blood were processed, with an average procedure time of 2.4 hours and a collection volume of 300 ml. Donors not receiving methylprednisolone (n = 80) had a mean total granulocyte count of 3.5 X 10(9)/litre (range 1.6-5.3 X 10(9)/litre) and mean granulocyte yields were 1 X 10(10) (range 0.2-3.0 X 10(10)). Those receiving 48 mg oral methylprednisolone 6-8 hours before the procedure (n = 320) had a mean granulocyte count of 6.3 X 10(9)/litre (range 3.2-11.4 X 10(9)/litre) and significantly superior mean granulocyte yields of 2.0 X 10(10) (0.3-6.5 X 10(10)) (P less than 0.05). For both groups the mean packed cell volume of 0.08 litre/litre (range 0.02-0.17) and platelet contamination 1.9 X 10(11) (range 0.3-5.0 X 10(11)). In all these procedures, hydroxyethyl starch was added to the blood entering the centrifuge channel. In none of the procedures were any untoward symptoms experienced by the donors. Light microscopy and ultrastructural studies showed no difference between control granulocytes and those collected following the addition of hydroxyethyl starch or after oral methylprednisolone. Similarly, granulocyte function measured with a random migration, chemotaxis, phagocytosis, and intracellular killing was not significantly different between control cells and those exposed to the sedimenting agent or the adrenocorticosteroids (P greater than 0.10). It is concluded that donor premedication with methylprednisolone significantly enhances granulocyte yields in the presence of hydroxyethyl starch and neither agent has any demonstrable effect on granulocyte morphology or function.

Leucocyte superoxide dismutase in rheumatoid arthritis

Superoxide dismutase (SOD) activity was measured in polymorphonuclear leucocytes (PMNLs) and mononuclear cells (MNCs) from 60 patients with rheumatoid arthritis (RA) and in 15 controls. In all patients and controls SOD activity (U/mg protein) in MNCs was twice that in PMNLs. SOD activity in PMNLs and in MNCs from patients with RA was significantly higher than that in controls. SOD activity in PMNLs (but not in MNCs) from patients treated with corticosteroids was significantly higher than that from patients treated with nonsteroidal anti-inflammatory drugs. There was no relation between SOD activity in both PMNLs and MNCs and either the patients' age, sex, duration of disease, serum immunoglobulin concentration, IgM rheumatoid factor, and copper level, or the degree of disease activity.