Effect of in vitro X-irradiation on lymphocyte and granulocyte function

Extracorporeal therapy of sepsis by purified granulocyte concentrates-ex vivo circulation model

BACKGROUND

Immune cell dysfunction is a central part of immune paralysis in sepsis. Granulocyte concentrate (GC) transfusions can induce tissue damage via local effects of neutrophils. The hypothesis of an extracorporeal plasma treatment with granulocytes is to show beneficial effects with fewer side effects. Clinical trials with standard GC have supported this approach. This ex vivo study investigated the functional properties of purified granulocyte preparations during the extracorporeal plasma treatment.

METHODS

Purified GC were stored for up to 3 days and compared with standard GC in an immune cell perfusion therapy model. The therapy consists of a plasma separation device and an extracorporeal circuit. Plasma is perfused through the tubing system with donor immune cells of the GC, and only the treated plasma is filtered for re-transfusion. The donor immune cells are retained in the extracorporeal system and discarded after treatment. Efficacy of granulocytes regarding phagocytosis, oxidative burst as well as cell viability and metabolic parameters were assessed.

RESULTS

In pGC, the metabolic surrogate parameters of cell functionality showed comparable courses even after a storage period of 72 h. In particular, glucose and oxygen consumption were lower after extended storage. The course of lactate dehydrogenase concentration yields no indication of cell impairment in the extracorporeal circulation. The cells were viable throughout the entire study period and exhibited preserved phagocytosis and oxidative burst functionality.

CONCLUSION

The granulocytes demonstrated full functionality in the 6 h extracorporeal circuits after 3 days storage and in septic shock plasma. This is demonstrating the functionality of the system and encourages further clinical studies.

Reference Results for Blood Parameter Changes and Recovery after Pelvic Radiation without Chemotherapy

Introduction: There are few reports on the effect of radiation alone on blood cells (without chemotherapy). We sought to develop a single source as a reference. Materials and Methods: For over 300 prostate cancer patients treated with radiation alone, we collected the baseline, end-of-treatment and three-month post-therapy complete blood counts (CBC). Results: The hemoglobin dropped by a mean of 1.00 g/dL (−7.1%), with an RBC count of 0.40 × 1012 (−8.6%) at the end of treatment and remained significantly (but <5%) below baseline at follow-up. Significant declines were seen in the levels of the granulocytes (−12.2%; −0.67 × 109), monocytes (−2.2%; −0.05 × 109) and platelets (−12.7%; −30.31 × 109) at the end of treatment, but all returned to baseline on follow-up. The neutrophils and basophils (the primary components of the granulocytes) suffered a significant decline but returned to baseline by the follow-up. The other granulocyte components, the eosinophils, did not decline significantly. The most dramatic decline was in the levels of lymphocytes −62.5% (−1.29 × 109), which were still significantly below baseline (−38%) after two years. Conclusion: The effect of radiation is mostly transitory, with some persistence in hemoglobin/erythrocyte levels (<5%). Lymphocytes are slower to recover, remaining significantly below baseline after two years. It is noteworthy that of the patients whose lymphocytes were in the normal range at the start of therapy, only 14% were below normal at follow-up. Radiation alone has negligible-to-modest long-term effects on blood counts.

Accumulation of Cytochrome b558 at the Plasma Membrane: Hallmark of Oxidative Stress in Phagocytic Cells

Neutrophils play a very key role in the human immune defense against pathogenic infections. The predominant players in this role during the activation of neutrophils are the release of cytotoxic agents stored in the granules and secretory vesicles and the massive production of reactive oxygen species (ROS) initiated by the enzyme NADPH oxidase. In addition, in living organisms, cells are continuously exposed to endogenous (inflammations, elevated neutrophil presence in the vicinity) and exogenous ROS at low and moderate levels (travels by plane, radiotherapy, space irradiation, blood banking, etc.). To study these effects, we used ROS induced by gamma radiation from low (0.2 Gy) to high (25 Gy) dose levels on PLB-985 cells from a myeloid cell line differentiated to neutrophil-like cells that are considered a good alternative to neutrophils. We determined a much longer lifetime of PLB-985 cells than that of neutrophils, which, as expected, decreased by increasing the irradiation dose. In the absence of any secondary stimulus, a very low production of ROS is detected with no significant difference between irradiated and non-irradiated cells. However, in phagocytosing cells, irradiation doses above 2 Gy enhanced oxidative burst in PLB-985 cells. Whatever the irradiation dose, NADPH oxidase devoid of its cytosolic regulatory units is observed at the plasma membrane in irradiated PLB-985 cells. This result is different from that observed for irradiated neutrophils in which irradiation also induced a translocation of regulatory subunits suggesting that the signal transduction mechanism or pathway operate differently in both cells.

Prolonged storage of purified granulocyte concentrates: Introduction of a new purification method

BACKGROUND

Use of donor granulocyte concentrate (GC) has been limited due to its short storage time of 6-24 h, which is partially due to residual red blood cells (RBCs) and platelets and the resulting lactate production leading to an acidotic milieu. To increase this storage time, we developed a closed system procedure compatible with standard blood bank technologies to remove RBC and platelets and to enrich the GC.

METHODS

Standard GCs (sGCs) were sedimented, washed twice with 0.9% sodium chloride (NaCl), and resuspended in blood group-identical fresh frozen plasma. The resulting purified GCs (pGCs) were then stored in platelet bags at a cell concentration of about 5 × 10⁷  ± 1.8 × 10⁷ leukocytes/ml without agitation at room temperature for up to 72 h. Cell count and viability, pH, blood gases, phagocytosis, and oxidative burst were monitored daily.

RESULTS

A significant reduction in RBC (98%) through sedimentation, and platelets (96%) by washing, purified the white blood cell (WBC) population and enriched the granulocytes to 96% of the WBC in the pGC. After 72 h of storage, over 90% of the initial WBC count of pGC remained, was viable (≥97%), and the granulocytes exhibited a high phagocytosis and oxidative burst functionality, comparable to sGC after 24 h.

CONCLUSION

Purification extends the maximum storage period of GC from 24 to 72 h and may therefore improve the availability of GC and its clinical use.

X-irradiation and gamma-irradiation inactivate lymphocytes in blood components

BACKGROUND

Irradiation of selected blood components is standard practice for the prevention of transfusion-associated graft-versus-host disease (TA-GvHD). Currently, gamma-irradiation is the most widely used form of irradiation, but there is an increasing interest in X-irradiation, which is considered to be functionally equivalent and safer. However, there is a paucity of contemporary data regarding the ability of X-irradiation to inactivate lymphocytes in blood components. Therefore, the effect of gamma- and X-irradiation on lymphocyte viability and function in blood components was compared.

STUDY DESIGN AND METHODS

Lymphocytes were isolated from venous blood by density gradient centrifugation, spiked into plasma/SSP+ to simulate a blood component, and either gamma- or X-irradiated. The phenotype of the isolated lymphocytes was confirmed. Lymphocyte viability was measured using a LIVE/DEAD assay, and function was assessed using mixed lymphocyte culture and CD69 expression post-phorbol-12 myristate 13-acetate (PMA) stimulation.

RESULTS

Lymphocyte viability and CD69 expression following PMA stimulation were significantly reduced by both gamma-irradiation and X-irradiation in simulated blood components. Allorecognition and allostimulation were also significantly reduced by both gamma-irradiation and X-irradiation.

CONCLUSION

Lymphocyte viability and function are reduced to a similar extent by gamma- and X-irradiation in simulated blood components. As such, X-irradiation is suitable for the irradiation of blood components and, in terms of lymphocyte inactivation, could be used instead of gamma-irradiation.

Prevention of Transfusion-Associated Graft-Versus-Host Disease With Blood Product Irradiation: The Past, Present, and Future

Transfusion-associated graft-versus-host disease (TA-GVHD) is a disease with a very high mortality rate. In this report, we discuss TA-GVHD from a historical perspective, highlight the pathogenesis of TA-GVHD, and emphasize the importance of blood product irradiation, which is a very effective means to prevent this disease. We summarize the current recommendations in different patient populations from different countries and review recent developments, such as alternatives for the use of radioactive materials. We also speculate on future directions.

Human T-lymphotropic virus and transfusion safety: does one size fit all?

Human T-cell leukemia viruses (HTLV-1 and HTLV-2) are associated with a variety of human diseases, including some severe ones. Transfusion transmission of HTLV through cellular blood components is undeniable. HTLV screening of blood donations became mandatory in different countries to improve the safety of blood supplies. In Japan and Europe, most HTLV-infected donors are HTLV-1 positive, whereas in the United States a higher prevalence of HTLV-2 is reported. Many industrialized countries have also introduced universal leukoreduction of blood components, and pathogen inactivation technologies might be another effective preventive strategy, especially if and when generalized to all blood cellular products. Considering all measures available to minimize HTLV blood transmission, the question is what would be the most suitable and cost-effective strategy to ensure a high level of blood safety regarding these viruses, considering that there is no solution that can be deemed optimal for all countries.

Quality control of blood irradiation: determination T cells radiosensitivity to cobalt-60 gamma rays

BACKGROUND

To identify the most appropriate dose for the prevention of transfusion-associated graft-versus-host disease, the radiosensitivity of T cells has been determined in blood bags irradiated with X-rays produced by a linear accelerator and gamma rays derived from the cesium-137 source of a specific irradiator. In this study, the influence of doses ranging from 500 to 2500 cGy was investigated on T cells isolated from red blood cell (RBC) units preserved with ADSOL and irradiated with a cobalt teletherapy unit.

STUDY DESIGN AND METHODS

A thermal device consisting of acrylic and foam was constructed to store the blood bags during irradiation. Blood temperature was monitored with an automated data acquisition system. Dose distribution in the blood bags was analyzed based on isodose curves obtained with a polystyrene phantom constructed for this purpose. The influence of cobalt-60 gamma radiation on T cells was determined by limiting-dilution analysis, which measures clonable T cells. T-cell content of the mononuclear cell population plated was assessed by flow cytometry with a monoclonal antibody specific for CD3.

RESULTS

Blood temperature ranged from 2 to 4.5 degrees C during irradiation. Dosimetry performed on the phantom showed a homogenous dose distribution when the phantom was irradiated with a parallel-opposite field. A radiation dose of 1500 cGy led to the inactivation of T cells by 4 log, but T-cell growth was observed in all experiments. At 2500 cGy, no T-cell growth was detected in any of the experiments and a greater than 5 log reduction in functional T cells was noted.

CONCLUSION

The results showed that a dose of 2500 cGy completely inactivates T cells in RBC units irradiated with cobalt-60 source.

Leakage of Potassium from Red Blood Cells following Gamma Ray Irradiation in the Presence of Dipyridamole, Trolox, Human Plasma or Mannitol

Transfusion-associated graft-versus-host disease (TA-GVHD) is a fatal complication of blood transfusion resulting from the contamination of blood products by leukocytes. In order to prevent this disease, gamma or X-ray irradiation of blood components,which can inactivate leukocytes, is currently used. However, the minimal doses needed to destroy lymphocytes promote the leakage of potassium from red blood cells (RBCs), which can induce other side effects, such as hyperpotassemia and cardiac arrest. The reactive oxygen species (ROS) generated by the irradiation of aqueous solutions may accelerate the leakage through oxidation of the RBC membrane. Here we studied the effect of dipyridamole, Trolox, human plasma or mannitol on the leakage of potassium from RBCs following irradiation. RBC preparations (hematocrit; 30%) containing antioxidants were irradiated at 30 Gy and stored at 4 degrees C for 7 d. The leakage of potassium from the RBCs caused by the irradiation was significantly suppressed by dipyridamole (more than 50 microM), Trolox (more than 5 mM) or human plasma (50%). Mannitol (80 mM) is used to inhibit hemolysis as a constituent of MAP solution, which is a solution used for the storage of RBC products in Japan. Here it was clarified that the leakage of potassium from not only irradiated but also non-irradiated RBCs was unexpectedly promoted by mannitol. The amount of mannitol in MAP solution may have to be reconsidered. The osmotic pressure of the RBC preparation increased in a manner dependent on the concentration of mannitol. The elevated osmotic pressure may promote the leakage. In conclusion, although antioxidants have the potential to suppress the leakage of potassium ascribed to the irradiation, the extent of the suppression (10-20%) by dipyridamole (DPM), Trolox or human plasma seems insufficient for the clinical use of these agents as an additive for MAP solution.

Prevention of transfusion-associated graft-versus-host disease by inactivation of T cells in platelet components

Patients with hematological malignancies and infants with congenital immunodeficiencies who received blood are two of many populations at risk for transfusion-associated graft-versus-host disease (TA-GVHD). Of the methodologies (eg, photoinactivation, peglyation, ultraviolet light, and irradiation) that can be used to prevent TA-GVHD, only irradiation of whole blood and cellular components is currently accepted practice of the US Food and Drug Administration (FDA). Among the newer methods that have been developed to reduce the risks of bacterial and viral contaminants of platelet transfusions, photochemical treatment (PCT) using psoralens and long-wavelength ultraviolet (UVA) irradiation modifies bacterial and viral genomes sufficiently to inhibit replication. Among a broad group of compounds, the synthetic psoralen compound amotosalen hydrochloride (HCl) (S-59) has been shown to be particularly effective in inactivating bacteria and viruses, without adversely affecting in vitro and in vivo platelet function.

In vitro and in vivo measurements of gamma-radiated, frozen, glycerolized RBCs

BACKGROUND

Transfusion-associated GVHD results from the presence of viable lymphocytes in transfused allogeneic blood components. Viable immunocompetent lymphocytes have been detected in RBCs that were frozen with glycerol and washed before transfusion.

STUDY DESIGN AND METHODS

The study reported here assessed the effect of irradiation on human RBCs frozen with 40-percent (wt/vol) glycerol and stored at -80 degrees C. In vitro and in vivo testing was done on human RBCs that were frozen with 40-percent (wt/vol) glycerol at -80 degrees C, with some units exposed to 2500 cGy of gamma radiation and others not irradiated, and that, after thawing and washing, were stored in a sodium chloride-glucose solution at 4 degrees C for 3 days before autologous transfusion.

RESULTS

The glycerol-frozen RBCs treated with 2500 cGy before deglycerolization had a mean freeze-thaw-wash recovery of 87 percent and a mean 24-hour posttransfusion survival of 86 percent after storage for 3 days at 4 degrees C in a 0.9-percent NaCl and 0.2-percent glucose solution. For the nonirradiated units, the mean freeze-thaw-wash recovery was 85 percent and the mean 24-hour posttransfusion survival was 83 percent.

CONCLUSION

These data show similar, acceptable results for RBCs frozen with 40-percent (wt/vol) glycerol at -80 degrees C and treated in the frozen state with 2500 cGy of gamma radiation and for RBCs that were not irradiated, all of which were washed and then stored in a sodium chloride-glucose solution for 3 days before autologous transfusion.

Assessment of donor T-cell function in cellular blood components by the CD69 induction assay: effects of storage, gamma radiation, and photochemical treatment

BACKGROUND

Functional donor T-lymphocytes in blood components may cause a variety of transfusion complications. A flow cytometric assay based on the measurement of induced CD69 expression may be an alternative to cell proliferation methods in determining the functional status of these cells in blood components.

STUDY DESIGN AND METHODS

Seven units of whole blood, RBCs, and platelet concentrates (PCs) were stored under blood bank conditions. Half of 3 PCs each were gamma-radiated or treated with UVA+psoralen; the other half served as controls. Samples were analyzed for phorbolester-induced expression of CD69 as an indicator of cell responsiveness and for exclusion of propidium iodide as a measure of cell membrane integrity and viability.

RESULTS

CD69 inducibility and propidium iodide exclusion decreased exponentially (half-life, 3. 3 and 8.1 days, respectively) during cold blood storage. Irradiation and UVA+psoralen treatment of PCs immediately reduced CD69 inducibility to 21 percent (controls, 82%; p = 0.004) and 12 percent (controls, 95%; p = 0.0008), respectively. The proportion of cells capable of propidium iodide exclusion was similar in treated samples and controls, but it declined faster in the treated samples during subsequent storage.

CONCLUSION

Flow cytometric measurement of CD69 induction can be adapted to provide quantitative assessment of T-cell function in blood components. Results obtained by the CD69 assay are in general agreement with those previously reported by use of proliferation methods; the assay may be useful for special applications in transfusion medicine.

Irradiation of platelet components: inhibition of lymphocyte proliferation assessed by limiting-dilution analysis

BACKGROUND

Using a limiting-dilution analysis (LDA) assay that measures clonigenic T cells, it has been demonstrated that, with 2500 cGy, there is no T-cell growth in red cell components irradiated in blood bags. In the current study, the LDA assay was used to investigate the effect of gamma radiation on the proliferative capacity of T cells in plateletpheresis components.

STUDY DESIGN AND METHODS

Platelets were collected by using an apheresis instrument and settings that provided sufficient mononuclear cells for the LDA assay. Platelet components (n = 8) were irradiated in 1-L plastic bags 24 hours after collection with 500, 1500, and 2500 cGy of gamma radiation in a stepwise manner. Mononuclear cells were isolated after each irradiation dose by the use of ficoll-hypaque. A density separation medium was used to reduce the platelet numbers. T cells were enumerated by fluorescence-activated cell sorter and functionally assessed by LDA assay, which quantified T cells proliferating in the presence of polyclonal stimuli and cytokines. The frequency of T-cell growth (f) was visually scored after 4 weeks of incubation at 37 degrees C. Data were calculated as f(experimental)/f(control) and expressed as log(10) reduction.

RESULTS

The T-cell content of the mononuclear cell population was 17 +/- 10.5 percent, which was unaltered by irradiation. After 500-cGy irradiation, functional T cells were reduced by 2.09 log(10). Irradiation with 1500 cGy resulted in a 3. 96 log(10) reduction, but viable clonable T cells were detected in all experiments. With 2500-cGy irradiation, no T-cell growth was detected; this represented a greater than 4.86 log(10) reduction.

CONCLUSION

As the dose of gamma radiation delivered to plateletpheresis components increased, the number of residual functional T cells decreased exponentially. Irradiation with 2500 cGy inactivates T cells in apheresis platelets, as measured by an LDA assay.

The irradiation of blood and blood components to prevent graft-versus-host disease: technical issues and guidelines

In recent years, there have been several advances in blood irradiation practice. These include a better definition of the most appropriate dose level that should be used when irradiating blood components. Commercial innovation has provided the tools for a quality assurance program to assess the dose that is delivered throughout the canister in a free-standing irradiator, and, through the use of radiation-sensitive indicator labels, to confirm that the irradiation process has taken place. With the apparent increased use of linear-accelerators to irradiate blood components, appropriate quality assurance measures need to be developed. The maximum storage period for irradiated red cells should be shorter than for nonirradiated red cells if the treatment is performed early during the storage period because irradiation reduces the in vivo 24-hour red cell recovery parameter. The storage period for irradiated platelets does not need to be modified. Some questions are being raised regarding whether fresh-frozen plasma should be irradiated to inactivate a small number of immunocompetent progenitor cells that may be present. Table 4 summarizes the practices that should be followed in connection with the technical issues that have been addressed in this article. These guidelines follow the recommendations issued in July 1993 by the FDA in the United States. This article and Tables 1 and 2 contain additional guidelines.

Transfusion and stem cell support in cancer treatment

Intensification of therapeutic regimens, improved patient survival, and advances in cytokine and cellular therapies have led to increasingly complex requirements for transfusion and stem cell support in cancer treatment. This article focuses on current and evolving issues in red blood cell, platelet, and granulocyte transfusion support, as well as measures to avoid increasingly important complications of transfusion therapy, such as alloimmunization, graft-versus-host disease, cytomegalovirus infection, and immunomodulation. Issues concerning current applications of hematopoietic stem cell transplantation and future prospects also are discussed.

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.

Radiation damage to the erythrocyte membrane: the effects of medium and cell concentrations

Human erythrocytes suspended in plasma, or in phosphate buffered saline (PBS), were exposed to ionizing radiation. Potassium leakage from irradiated erythrocytes is significantly higher in PBS than in plasma. The potassium leakage decreases when PBS is gradually replaced by plasma. These findings suggest that some of the plasma constituents have radioprotective properties. The potassium leakage per cell is independent of the hematocrit, Hct. The potassium leakage is attributed to the formation of radiation defects in the membrane. Analysis of the effect of radiation dose, plasma and cell concentrations on the product of the number and surface area of the radiation defects indicates that the radiation damage is mainly due to the direct formation of free radicals in the cell membrane. The radioprotective effect of plasma is attributed to surface reactions of these free radicals with plasma constituents adsorbed on the membrane.

Transfusion-induced graft-versus-host disease in patients with malignant lymphoma. A case report and review of the literature

A case of transfusion-induced graft-versus-host disease (GVHD) occurring in a 31-year-old female with Hodgkin's disease in complete remission is reported. Clinical features are similar to 19 other reported cases of transfusion-induced GVHD associated with malignant lymphoma. The lack of relationship with underlying histology or disease stage and the nearly uniformly fatal outcome underscores the importance of prophylactic irradiation of blood products given to patients with malignant lymphoma undergoing therapy.

Irradiated blood platelet concentrates stored for five days--evaluation by in vitro tests

Platelet concentrates, irradiated with 15 Gy and stored for 5 days at room temperature under standardized conditions, were evaluated by in vitro tests and electron microscopy, in a paired study with nonirradiated platelets from the same concentrates, to investigate their usefulness for transfusion. The results showed no significant differences between the two groups in pH, pO2, pCO2, in vitro platelet aggregation, LDH, beta-thromboglobulin and thromboxane-B2. Examination by electron microscopy showed a higher degree of degranulation in the 5-day-old platelets but no certain difference between irradiated versus nonirradiated platelets. On the basis of satisfactory in vitro storage properties, platelet concentrates can be stored for 5 days in PL-1240 bags after irradiation. However, we recommend irradiation just before transfusion whenever possible.

Effects of storage and radiation on human neutrophil function in vitro

To better understand the process of time-related functional deterioration which occurs in human polymorphonuclear leukocytes (PMNs), we examined the effects of in vitro storage on multiple functional parameters of human PMNs. Single-donor, phlebotomy-collected PMNs were stored at both room temperature and 37 degrees C for 24 and 48 h, then compared to fresh cells from the same donor. Similar numbers of cells were recovered from each storage condition. Cell viability decreased after 37 degrees C storage for 48 h. Cells stored at room temperature for 24 h showed significant depression of multiple functions (bactericidal activity, chemotaxis, aggregation, superoxide production, and oxygen consumption) compared to fresh cells. They contained less vitamin B12 binding protein activity than fresh cells, and by fluorescence-activated cell-sorter analysis, their forward light scatter and membrane depolarization responses were abnormal. For all parameters examined, cells stored at 37 degrees C were more abnormal than cells stored at room temperature. Stored cells from a patient with myeloperoxidase deficiency lost bactericidal and chemotactic activity after storage at 37 degrees C for 24 h, but cells from a patient with chronic granulomatous disease retained their original bactericidal and chemotactic activity after 37 degrees C storage for 24 h. Radiation, in doses used to prevent graft vs. host disease in leukocyte-transfusion recipients (2500-5000 rads) caused a significant decrease in the mean percentage of continuous flow centrifugation leukapheresis (CFCL) collected PMNs capable of reducing nitroblue tetrazolium. Human PMNs show deterioration of multiple in vitro functions when they are stored and are susceptible to damage by radiation when they are collected by CFCL.

Rationale and recommendations for the irradiation of blood products

Blood products are often irradiated to prevent proliferation of lymphocytes which could cause graft-vs.-host disease in immunocompromised recipients. The effects of irradiation on the function of blood components is discussed. It is concluded that 1500 rad is sufficient to prevent lymphocyte proliferation and production of graft-vs.-host disease in vivo, although 10 to 20% of lymphocytes are still capable of proliferation in vitro after 1500 rad. Neutrophils and erythrocytes are extremely radioresistant and their function is unaffected by 1500 rad. There is limited data to suggest that platelet yields may be slightly reduced following irradiation. Guidelines for the use of irradiated blood products are suggested.

The immunodeficiency of bone marrow-transplanted patients. The effect of patient lymphocytes on the response of donor lymphocytes to mitogens and allogeneic cells

Lymphocytes from patients after bone marrow transplantation (BMT) are in most cases predominantly of the Leu-2+ (cytotoxic/suppressor) phenotypes and are almost unresponsive to mitogens. In contrast, normal Leu-3+-depleted, Leu-2+-enriched lymphocyte suspensions retain approximately 50% of the mitogenic response compared with that of unseparated cells. To investigate whether this discrepancy was due to active suppression, we selected nine BMT patients from whom sufficient numbers of cells were available and whose lymphocyte phenotypes were predominantly Leu-2+ after BMT. These post-BMT lymphocytes were tested for functional suppressor activities against donor and recipient pre-BMT lymphocytes in the lymphocyte transformation test. None of these post-BMT cells suppressed the response of donor or pre-BMT cells to phytohaemagglutinin A or concanavalin A. In contrast, the response of donor cells in mixed lymphocyte cultures to HLA-DR-different third-party cells was suppressed by highly X-irradiated post-BMT cells by approximately 40%. Addition of T-cell growth factor (= interleukin 2 (IL-2)) or X-irradiated donor cells to post-BMT lymphocytes partially restored the mitogenic response. These findings indicate that the early post-BMT cells lack production of IL-2 but are capable of responding to IL-2 and that the almost extinct mitogen response of these cells is due to immaturity rather than active suppression. The suppression of the allogeneic but not the mitogenic response might be explained by differences in the modes of activation; for example, the allogeneic response must involve the T-cell receptor, while the mitogenic response may not.

Chronic granulomatous disease associated with chronic glomerulonephritis

A boy with chronic granulomatous disease (CGD) developed glomerulonephritis at the age of 12 years. The glomerulonephritis progressed to terminal uraemia at age 15 when maintenance haemodialysis was started. The clinical course was complicated by pulmonary aspergillosis and Pseudomonas septicaemia from which he eventually died. The glomerulonephritis was of unknown origin, and a possible relationship between CGD and glomerulonephritis is discussed.

Amelioration of hydroxyurea-induced suppression of phagocytosis in human granulocytes by free radical scavengers

The exposure of human circulatory white cells in vitro to 0.1-1-10 mol/l hydroxyurea (HU) for 20 h induced a progressive dose-dependent suppression of the phagocytic activity of granulocytes. The suppressing effect of 20 h exposure to 1 mol/l HU was used to examine the protection afforded by free radical scavengers against HU-induced cytotoxicity. It has been found that, in the suitable concentration of the protecting agent, a substantial protective effect of sodium benzoate, acetylosalicylic acid, alpha-tocopherol, ascorbic acid, catalase, peroxidase or superoxide dismutase can be achieved.

Defective neutrophil motility in patients with primary ciliary dyskinesia

Microtubules are important in the regulation of the motile functions of a variety of cells, including leukocytes, ciliated cells and spermatozoa. Polymorphonuclear leukocyte function was studied in ten patients with primary ciliary dyskinesia, an inherited disorder of microtubules in sperm tails and cilia. Neutrophil chemotaxis in Boyden chambers was slightly reduced, but only one patient showed a migration below normal values. In vivo mobilization of polymorphonuclear leukocytes into skin windows was also slightly decreased. In contrast, neutrophil polarization and orientation was normal. The bactericidal activity of neutrophils from patients with primary ciliary dyskinesia was normal, while the ingestion of bacteria was decreased. The abnormalities of neutrophil function in patients with primary ciliary dyskinesia are related to motility. It is suggested that the microtubule defect responsible for the abnormal pattern of ciliary beating is a general abnormality also responsible for the depression of polymorphonuclear leukocyte motility.

A variant form of X-linked chronic granulomatous disease with normal nitroblue tetrazolium slide test and cytochrome b

Chronic granulomatous disease was diagnosed in a boy who suffered from severe generalized infections. Family investigations revealed the inheritance of the disease to be X-linked. However, unlike other cases of X-linked chronic granulomatous disease, the membrane oxidase of the neutrophils from this patient was not totally defective and sufficient activity was left to result in a normal phorbol myristate acetate-stimulated nitroblue tetrazolium slide test. Also, unlike the usual findings in X-linked chronic granulomatous disease, cytochrome b was present in normal amounts in the neutrophils from this patient. The cytochrome was normal, judged from its midpoint potential of -245 mV and its ability to bind CO. It is thus apparent that X-linked chronic granulomatous disease may result from at least two different defects and that the phorbol myristate acetate stimulated nitroblue tetrazolium slide test fails to detect some cases.

Impaired in vitro function of neutrophils in Crohn's disease

The in vitro function of neutrophil granulocytes from 11 patients with Crohn's disease was studied. Nitroblue tetrazolium reduction test results were normal in all patients. Increased intracellular survival of Staphylococcus aureus, impaired glucose-1-14C metabolism of the granulocytes at rest and during phagocytosis, and reduced and delayed staphylococcus-induced granulocyte chemiluminescence response were recorded in the patients with Crohn's disease, a defect that may be involved in the pathogenesis of the chronic granulomatous inflammatory response in this disease.