Genetic studies in NZB mice. I. Spontaneous autoantibody production.

The appearance of naturally occurring thymocytotoxic autoantibodies (NTA) and spontaneously produced antibodies to single-stranded DNA (ssDNA) was studied in NZB, and DBA/2 mice and their F1 and backcross progeny. NTA production was markedly decreased in males; however, castrated males produced quantities of NTA similar to those of females. Because the amount of NTA was influenced by sex hormones, it was necessary to gonadectomize all progeny to determine the mode of inheritance. Such studies suggested that NTA production was determined by a single locus with a gene dosage (codominant) mode of expression. The spontaneous production of antibodies to ssDNA appeared to be inherited as a single dominant genetic trait. The quantity of anti-ssDNA was also found to be under additional regulation; either a gene dosage effect or more likely a regulatory gene. The genes controlling the presence and quantity of ssDNA antibodies were not linked to the gene controlling the appearance of NTA.

Ribavirin: efficacy in the treatment of murine autoimmune disease.

Ribavirin, a drug with known antiviral activity, was given to mice with established lupus nephritis. Ribavirin was effective in prolonging survival, reducing the titer of antibodies to DNA, and reversing proteinuria. Other antiviral agents were not effective in the dosages used.

Selenium and the immune response: 1. Modulation of alloreactive human lymphocyte functions in vitro.

A role for the dietary trace mineral element selenium in the reduction of cancer incidence has been documented in numerous epidemiological and experimental studies. The precise mechanism of this antitumor effect is not well understood, but published data suggest that both inhibition of tumor cell growth and enhancement of host immunity are likely to be involved. In this study we report that selenium at physiologic concentrations can inhibit human lymphocyte proliferation in response to irradiated tumor cells in mixed lymphocyte/tumor cell cultures (MLTC). In addition, we demonstrate that the various lymphocyte functional activities generated in these cultures exhibit different levels of sensitivity to the effects of selenium. The generation of suppressor-cell activity in MLTC was strongly inhibited by the presence of physiologic levels of selenium, while the development of cytotoxic T-lymphocyte activity in identical cultures was not affected by selenium. Production of interleukin-2 in these cultures showed an intermediate sensitivity to the effects of selenium. Thus, selenium appears to be capable of selectively regulating the generation of functional lymphocyte subsets in vitro. Such selective regulation could explain the published effects of selenium on immunity and would be consistent with a role for immunity in the observed reduction of cancer incidence associated with elevated selenium intake.

Selenium and the immune response: 2. Enhancement of murine cytotoxic T-lymphocyte and natural killer cell cytotoxicity in vivo.

An inverse correlation between cancer incidence and dietary intake of the trace mineral element selenium has been well established in epidemiological and experimental studies. The mechanisms for this chemoprotective effect are unresolved. Much attention has been focused on the antiproliferative effects of selenium on various normal and neoplastic cell types. However, dietary selenium supplementation can also enhance the expression of various humoral and cellular immune responses. In examining the effects of dietary selenium on cell-mediated immunity in mice, we observed that selenium supplementation caused the enhanced expression of spontaneous natural killer (NK) cytotoxicity in spleen cells and of specific cytotoxic T-lymphocyte (CTL) cytotoxicity in peritoneal exudate cells (PEC). NK activity of spleen-cell suspensions from selenium-supplemented mice increased an average of 70% over that of the control group (basal diet). Cytotoxic activity of PEC from mice injected with tumors intraperitoneally peaked earlier in selenium-supplemented animals, and the appearance of cells staining positively for Thy 1.2 surface antigen in selenium-supplemented animals also preceded the values observed in control animals. We propose here that enhancement of in vivo cytotoxic mechanisms, is likely to act synergistically with tumor growth inhibition in the reduction of tumor incidence associated with selenium intake.

Marrow transplantation for stable-phase chronic granulocytic leukemia.

Ten patients with chronic granulocytic leukemia in the stable phase underwent marrow transplantation from HLA-identical siblings (nine cases) or an identical twin (one case) following preparation with cytarabine, cyclophosphamide, and total body irradiation. Marrow cytogenetics on all patients prior to transplantation revealed the Philadelphia chromosome without other evidence of aneuploidy. The immediate posttransplant course was in most cases relatively uncomplicated with only two serious infections and one death. All patients recovered with cytogentically normal marrow and leukemia has recurred only in the syngeneic transplant recipient. At present, nine patients are surviving from 358 to 961 days (median 597 days) after bone marrow transplantation. Bone marrow transplantation is capable of eliminating the abnormal clone of myeloid cells in patients with stable-phase chronic granulocytic leukemia and can be performed relatively safely in this "healthy" group of patients.

Celastrol inhibits inflammatory stimuli-induced neutrophil extracellular trap formation.

Neutrophil extracellular traps (NETs) are web-like structures released by activated neutrophils. Recent studies suggest that NETs play an active role in driving autoimmunity and tissue injury in diseases including rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE). The purpose of this study was to investigate if celastrol, a triterpenoid compound, can inhibit NET formation induced by inflammatory stimuli associated with RA and SLE. We found that celastrol can completely inhibit neutrophil oxidative burst and NET formation induced by tumor necrosis factor alpha (TNFα) with an IC50 of 0.34 µM and by ovalbumin:anti-ovalbumin immune complexes (Ova IC) with an IC50 of 1.53 µM. Celastrol also completely inhibited neutrophil oxidative burst and NET formation induced by immunoglobulin G (IgG) purified from RA and SLE patient sera. Further investigating into the mechanisms, we found that celastrol treatment downregulated the activation of spleen tyrosine kinase (SYK) and the concomitant phosphorylation of mitogen-activated protein kinase kinase (MAPKK/MEK), extracellular-signal-regulated kinase (ERK), and NFκB inhibitor alpha (IκBα), as well as citrullination of histones. Our data reveals that celastrol potently inhibits neutrophil oxidative burst and NET formation induced by different inflammatory stimuli, possibly through downregulating the SYK-MEK-ERK-NFκB signaling cascade. These results suggest that celastrol may have therapeutic potentials for the treatment of inflammatory and autoimmune diseases involving neutrophils and NETs.

Association of malondialdehyde-acetaldehyde (MAA) adducted proteins with atherosclerotic-induced vascular inflammatory injury.

Atherosclerosis is a vascular injury characterized by elevated tissue levels of tumor necrosis factor-alpha (TNF-alpha), increased expression of endothelial cell adhesion molecules, and vascular wall inflammatory cell infiltration. Foam cells are associated with atherosclerotic plaque material, and low density lipoprotein (LDL) is a lipid component of foam cells. Malondialdehyde (MDA) is an oxidative product of unsaturated fatty acids and is also present in atherosclerotic lesions. MDA-modified (adducted) proteins, including MDA-modified LDL, are present in atherosclerotic human vascular tissue. Acetaldehyde (AA) is the major metabolic product of ethanol oxidation. Both MDA and AA are highly reactive aldehydes and will combine with proteins to produce an antigenically distinct protein adduct, termed the MAA adduct. This study demonstrates that proteins modified in the presence of high concentrations of MDA can produce MAA-modified proteins in vitro. In addition, MAA adducted proteins are capable of inducing rat heart endothelial cell cultures (rHEC) to produce and release TNF-alpha, and cause rHEC upregulation of endothelial adhesion molecule expression, including ICAM-1. These adhesion molecules are required for circulating inflammatory cells to adhere to endothelium which allows inflammatory cell tissue infiltration. Additionally, MAA modified proteins were defected in human atherosclerotic aortic vascular tissue but not in normal aortic tissue. Since atherosclerosis is associated with an inflammatory vascular injury characterized by elevated tissue TNF-alpha concentrations and inflammatory cell infiltration, these data suggest that MAA-adducted proteins may be formed in atherosclerotic plaque material and may be involved in the inflammatory reaction that occurs in atherosclerosis. These data further suggest that previous studies demonstrating MDA modified protein in atherosclerotic plaque may in fact have MAA modified proteins associated with them.

Rapid recovery of non-hemolyzed serum and untraumatized cells by using a new method of blood defibrination in vitro.

Platelet-free cellular elements and non-hemolyzed, chemically unaltered serum are important research components of the cellular immunology laboratory. Both can be recovered from the same peripheral blood sample if it is properly defibrinated. The numbers of cells recovered from heparinized aliquots of blood from healthy donors were not significantly different from the numbers of mononuclear leukocytes, polymorphonuclear leukocytes, and erythrocytes recovered from blood samples which had been mechanically defibrinated in vitro with a stationary, cone-shaped 'TP'-like device which we here describe. Compared with serums obtained from clotted blood, or from blood defibrinated by using glass beads, we found that serums from blood defibrinated with the 'TP'-like device had the lowest detectable levels of hemoglobin, free DNA, or LDH. Serums from TP-defibrinated blood were not different from clotted serum samples with regard to the function of the classical complement pathway, the alternative complement pathway, C4 hemolytic activity, and most serum chemistries. Use of the TP-defibrinator in immunology laboratories is an ideal way to prepare blood for rapid isolation of cellular elements and non-hemolyzed serum from the same sample.

Nosocomial Legionnaires' disease. Occurrence in recipients of bone marrow transplants.

Nosocomial pneumonia caused by Legionella pneumophila serogroup 1 occurred in five patients after bone marrow transplantation for hematologic malignancies. Two patients died as a result of the infection despite treatment with erythromycin. Serologic screening revealed no other cases of Legionnaires' disease in 40 consecutive recipients of bone marrow transplants, giving a frequency of infection of 13 percent. These five cases represent 23 percent of the pneumonia occurring in this group of patients. Patients undergoing bone marrow transplantation are highly susceptible to infectious complications. Legionnaires' disease must now be added to the list of pathogens infecting this group of patients. Erythromycin is not generally a part of standard empiric antibiotic regimens in febrile neutropenic patients, but appears to be a reasonable addition when pneumonia does not respond to conventional, empiric treatment. Even with appropriate therapy, Legionnaires' disease remains a highly lethal infection in immunocompromised hosts.

The use of partially matched, unrelated donors in clinical bone marrow transplantation.

It is estimated that 60-70% of patients who might benefit from a bone marrow transplant will not have a suitably matched, related donor. We have, therefore, designed a clinical experiment to test the safety and feasibility of using marrow from partially matched, unrelated donors. This paper details our transplant experience in the first eight patients with leukemia. The first four patients had advanced leukemia at the time of transplantation. Each showed hematopoietic recovery, but all died from septic complications largely related to extended neutropenia encompassing both the pre-marrow-grafting and the post-marrow-grafting period. The next four patients were in remission at the time of transplantation. Each showed prompt and sustained hematopoiesis with variable graft-versus-host disease (GVHD). No acute or chronic GVHD was seen in two patients, grade II (skin only) was seen in one patient, and grade IV (skin, liver, and gut) was seen in one patient. One patient has died from sepsis five-and-one-half months following transplantation, and three are alive and well six-and-one-half to nine-and-one-half months postengraftment. This preliminary experience, together with several case reports in the literature, leads us to conclude that bone marrow transplantation with partially matched, unrelated marrow is a safe and feasible approach. If these results are confirmed by longer follow-up in a larger group of patients, the development of marrow donor pools would appear to be justified.

N-(methylamino)isobutyric acid inhibits proliferation of CFSC-2C hepatic stellate cells.

Activation of hepatic stellate cells (HSCs) involves the induction of ECM protein synthesis and rapid cell proliferation. Thus, agents that interfere with either process could potentially mitigate the development of liver disease by reducing the synthesis of proteins associated with fibrosis or by reducing the number of activated HSC. Previously, we described that the non-metabolizable amino acid analog N-(methylamino)isobutyric acid (MeAIB) reduced hepatic collagen content of rats in a model of CCl(4)-induced liver injury, and in vitro studies using CFSC-2G cells indicated that MeAIB directly reduced collagen synthesis. However, the MeAIB-mediated reduction of hepatic collagen, in vivo, following liver injury was associated with a decrease in hepatic alpha-smooth muscle actin (alpha-SMA) which suggested that MeAIB also inhibited the activation of HSCs. Because HSC activation is inseparable from proliferation, the purpose of this study was to examine the effect of MeAIB treatment on the proliferation of HSCs in an in vitro model utilizing CFSC-2G cell cultures. In these studies, MeAIB effectively inhibited the proliferation of CFSC-2G cells by interfering with the progression of the cells through the G(1)-phase of the cell cycle which delayed entry into S-phase. MeAIB prevented the phosphorylation of p70S6 kinase (p70S6K) at Thr389 and reduced the phosphorylation at Thr421/Ser424. Because p70S6K is required for G(1)-cell cycle progression and is known to be regulated by nutrient availability, this correlates well with MeAIB interfering with the proliferation of CFSC-2G HSCs. In addition, the rate of protein synthesis was reduced by MeAIB treatment following mitogenic stimulation, which agrees with a p70S6K-mediated reduction in translation. These data are consistent with MeAIB inhibiting the proliferation of CFSC-2G cells by altering the mitogen activated pathway(s) leading to phosphorylation of p70S6K by a yet to be described mechanism.

Specificity of N-ethyl lysine of a monoclonal antibody to acetaldehyde-modified proteins prepared under reducing conditions.

A monoclonal antibody has been developed that recognizes only protein-acetaldehyde (AA) adducts prepared under reducing conditions: 5 mM AA with 30 mM sodium cyanoborohydride overnight at 37 degrees. This monoclonal antibody is a mouse IgG2b that has been designated RT1.1. The primary adduct formed when proteins are exposed to acetaldehyde under reducing conditions is N-ethyl lysine (NEL). To examine the epitope specificity of RT1.1, inhibition ELISAs were developed using NEL and other possible inhibitors, such as arginine, ethylamine, lysine and proteins modified with AA under non-reducing conditions. RT1.1 (at half-maximum optical density, 50 ng/mL) was inhibited only by NEL and was independent of the carrier or the pH of the buffer used in the ELISA. Further evidence indicating that NEL is the epitope recognized by RT1.1 was obtained using mouse and human epidermal growth factor (EGF). Both proteins contain one alpha amino group but only the human-EGF contains lysine residues with epsilon amino groups. In experiments where these two proteins were modified with AA under reducing conditions, RT1.1 reacted only with human-EGF. These studies demonstrate that RT1.1 is specific for NEL that is formed by the ethylation of proteins with acetaldehyde under reducing conditions. Additionally, these studies demonstrate that the procedures and methods used herein may be useful for characterizing other antibodies prepared to AA-modified proteins under a variety of defined in vitro chemical conditions.

Monoclonal and polyclonal antibodies recognizing acetaldehyde-protein adducts.

Studies have investigated the hypothesis that metabolically derived acetaldehyde (AA) is capable of complexing with liver cell proteins to form AA-protein adducts that are capable of acting as antigens and inducing an immune response, as detected by the formation of unique antibodies. In an effort to better characterize and describe these adducts, mouse monoclonal and rabbit polyclonal antibodies specific for antigens prepared with AA under non-reducing (physiologic) and reducing (presence of sodium cyanoborohydride) conditions have been prepared. Two monoclonal antibodies were developed. The first antibody was RT1.1, which is specific to N-ethyl lysine (NEL); it is of the IgG2b isotype and recognizes all proteins modified with AA under reducing conditions. The other monoclonal antibody, NR-1, was of the IgG3 isotype; it recognizes proteins modified with AA under non-reducing conditions and cannot be inhibited by NEL. Affinity-purified and/or absorbed polyclonal antibodies were also produced to these epitopes. Using this panel of monoclonal and affinity-purified polyclonal antibodies, unique antigen-antibody binding occurred that: (1) detected only NEL; (2) reacted with the alpha-amino group on proteins prepared under reducing conditions; and (3) detected adducts on proteins prepared under non-reducing conditions. However, the only antibodies that recognized antigen(s) from alcohol-fed rat livers were those that were not specific to NEL or the alpha-amino group modified under reducing conditions. These data indicate that the relevant adduct in alcohol-fed rat livers is not NEL, and that it presumably is related to proteins modified with AA under non-reducing conditions.

Allogeneic bone marrow transplantation in patients with lymphoma relapsing after autologous marrow transplantation.

Two patients who underwent autologous bone marrow transplantation for recurrent non-Hodgkin's lymphoma relapsed at 46 and 28 days after the transplant. Both patients had an HLA-identical sibling and were treated with high-dose chemotherapy and allogeneic marrow transplantation. One patient is now 24 months after the allogeneic transplant without evidence of disease. The second patient died on day 7 with interstitial pneumonia. We conclude that high-dose therapy and allogeneic bone marrow transplantation after failure of autologous transplantation for non-Hodgkin's lymphoma is feasible and should be considered in young patients with HLA-identical siblings.

Intravenous immunoglobulin in rheumatic disease.

With the advent of numerous commercial preparations of intravenous immunoglobulin preparations since 1981, it is now possible to administer these preparations in significant quantities to cause elevation of serum immunoglobulin levels both in patients with antibody-deficient states and in those with normal circulating immunoglobulin levels. This led to a report of dramatic improvement of thrombocytopenia in a child with agammaglobulinemia following the use of intravenous immunoglobulin preparations for recurrent infections, and further studies in both children and adults with associated symptoms suggested therapeutic efficacy of intravenous immunoglobulin preparations in controlling autoimmune symptoms.

Pure red cell aplasia following ABO mismatched marrow transplantation for chronic lymphocytic leukemia: response to antithymocyte globulin.

Pure red cell aplasia was observed in a 28 year old woman following a major ABO mismatched allogeneic bone marrow transplant for chronic lymphocytic leukemia. No evidence of red blood cell production was observed for more than one year following transplant despite the absence of high isohemagglutinin titers. Treatment with antithymocyte globulin resulted in prompt restoration of reticulocytosis. Therapy with antithymocyte globulin should be considered in these instances when red cell aplasia follows mismatched allogeneic marrow transplantation.

A comparison of bone marrow transplantation with maintenance chemotherapy for patients with acute nonlymphoblastic leukemia in first complete remission.

Twenty patients treated with maintenance chemotherapy for acute nonlymphoblastic leukemia after achieving complete remission were compared with 13 patients who underwent bone marrow transplantation from an HLA-identical sibling. The median age was 27 years for both maintenance chemotherapy patients (range 17-42 years) and for patients undergoing bone marrow transplantation (range 16-42 years). The 1-year survival for maintenance chemotherapy was 80% vs. 54% with bone marrow transplantation (p = NS). Complete remission durability was 70% at 1 year for maintenance chemotherapy (34% projected for 5 years) compared with no relapses in the first year with bone marrow transplantation (p = 0.01). Patients on maintenance chemotherapy were hospitalized for an average of 22 days (range 0-171 days) during the first 12 months of treatment. Patients undergoing bone marrow transplantation were hospitalized for an average of 82 days (range 41-113 days) in the same time period. Severe hematologic toxicity was seen in 13/13 bone marrow transplantation patients and 6/20 maintenance chemotherapy patients. Chronic graft-vs.-host disease occurred in 3/7 surviving bone marrow transplantation patients. Maintenance chemotherapy had an average first year cost of +3,076.00 for patients who did not relapse and +48,827.00 for patients that relapsed. The first year costs for bone marrow transplantation averaged +84,102.00. Thus, maintenance chemotherapy was associated with a better early survival, less toxicity, and lower cost than bone marrow transplantation in the first year after initiating therapy. However, fewer relapses with bone marrow transplantation suggest that it will yield a higher long-term survival rate.

Toxic shock syndrome: a retrospective study of 25 cases from Iowa.

We reviewed retrospectively the clinical records of 25 women ages 13 to 41 years who had diagnosed illnesses compatible wtih toxic shock syndrome (TSS). Cases occurred between January 1976 and October 1980. Fourteen confirmed TSS cases and 11 probable TSS cases were identified. In each case initial symptoms occurred in association with menstrual bleeding and tampon use. All patients were febrile. Hypotension occurred in 20 cases, but five patients with milder illness remained normotensive. An erythematous rash occurred in 20 cases. Desquamation occurred in convalescence in all but two cases. Complications included delirium or coma, acute renal failure, and respiratory distress syndrome. Thirteen patients had recurrences of TSS. S. aureus was isolated from the vagina or cervix in 75% of cases. There is a spectrum of severity associated with TSS. Strict diagnostic criteria established heretofore for epidemiologic studies of TSS may not be met by all cases of TSS.

In vitro regulation of human lymphocyte proliferation by selenium.

A chemoprotective role for dietary selenium in malignancy has been well documented in numerous epidemiological and experimental studies. The precise mechanisms of this relationship are not understood, but may be related to observations that selenium can inhibit the proliferation of various normal and neoplastic cells, both in vivo and in vitro. In this study, we present evidence that selenium at physiologic concentrations can effectively inhibit the overall proliferation of human lymphocyte populations in response to various immune stimuli in vitro, including mixed lymphocyte response and response to soluble antigen (tetanus toxoid). This inhibition was reversible, indicating that selenium was not toxic to the lymphocytes at these concentrations. Preliminary data from our laboratory indicate that the antiproliferative effects of selenium may be specific for certain lymphocyte subsets. Similar modulation of immune responses in vivo could enhance various humoral and cellular immune mechanisms. Together with published evidence that selenium can inhibit tumor cell proliferation, these data may help to explain the decreased incidence of cancer associated with elevated selenium intake.

Efficacy of triple DMARD therapy in patients with RA with suboptimal response to methotrexate.

Rheumatoid arthritis (RA) has a profound effect on patients, producing significant morbidity and in some cases mortality. Because of this, most rheumatologists are moving to disease modifying antirheumatic drug (DMARD) therapy earlier in the course of RA. Methotrexate (MTX) has become the initial DMARD of choice for most rheumatologists. Unfortunately, treatment of RA with a single DMARD, including MTX, often results in a suboptimal response. Therefore, most rheumatologists are now using combinations of DMARD to treat patients with RA who have had incomplete responses to single DMARD therapy. The Rheumatoid Arthritis Investigational Network (RAIN) reported the results of a double blind, controlled comparison of triple drug therapy (MTX-sulfasalazine-hydroxychloroquine) against MTX alone, and against the combination of hydroxychloroquine and sulfasalazine. Twenty-eight patients who had suboptimal responses to MTX or the combination of sulfasalazine and hydroxychloroquine were then treated with triple therapy in an open label study. Fourteen had previously failed MTX therapy, and 14 had previously failed combination therapy with sulfasalazine and hydroxychloroquine. Both groups had statistically significant improvements in sedimentation rates, morning stiffness, swollen joint scores, tender joint scores, patient global status assessment, and physician global status assessment. Statistical significance was reached for all these variables for patients in both groups, but improvement was greater for the patients in the sulfasalazine-hydroxychloroquine group. Patients with RA who have had suboptimal responses to MTX, or to the combination of sulfasalazine-hydroxychloroquine, show both statistical and clinically significant improvement in multiple clinical variables when treated with the combination of MTX 17.5 mg/week, sulfasalazine 500 mg bid, and hydroxychloroquine 200 mg bid.