European ancestry decreases the risk of early onset, severe lupus nephritis in a single center, multiethnic pediatric lupus inception cohort.

PURPOSE: To determine whether pediatric SLE patients without European ancestry are at higher risk for development of severe lupus nephritis (ISN/RPS class III, IV or V). METHODS: Ninety-eight of 101 patients with pediatric SLE (age <18 years at diagnosis) were enrolled. Race/ethnicity of four grandparents, socioeconomic status (SES) and language proficiency were collected. The primary outcome was time to development of severe lupus nephritis. RESULTS: Based on patient report of four grandparent ancestry, 29% had at least one grandparent of European ancestry (14% had all four grandparents of European ancestry). Patients without European ancestry were 46% Hispanic, 47% Asian, and 3% African American. In the entire 98 patient cohort, 12% had ≥3 different ancestries. Patients without European ancestry had significantly lower SES levels and English proficiency. There was no significant difference between patients with or without European ancestry in duration of SLE, age of onset, and lag time between symptoms and diagnosis. Patients with at least one grandparent of European ancestry had a decreased risk of developing severe lupus nephritis, which remained significant after controlling for age, gender, SES and English proficiency (hazard ratio 0.4, 95% confidence interval 0.2-0.9). CONCLUSION: This study demonstrates that presence of at least one grandparent of European ancestry decreases the risk of severe lupus nephritis, a finding that is not explained by measurable socioeconomic differences and language barriers.

A randomized trial of methotrexate in newly diagnosed patients with type 1 diabetes mellitus.

The aim of this study was to determine whether low-dose, oral methotrexate therapy would prolong the remission phase at the onset of Type 1 diabetes. Ten newly diagnosed, nonacidotic, ICA-positive, Type 1 diabetics were randomly assigned to receive either methotrexate (5 mg/m(2)/week) or no immunosuppressive treatment. The study was not blinded and no placebo was given. Endogenous insulin production was assessed every 3 months by fasting and Sustacal-stimulated C-peptide levels. Methotrexate therapy was not beneficial in prolonging islet survival as assessed by fasting and stimulated C-peptide levels. Insulin requirements were generally lower in the control group, and islet failure, determined by an insulin requirement of >0.7 u/kg/day, occurred earlier for those receiving MTX (P < 0.02). Side effects of methotrexate treatment were minimal. There was no benefit from methotrexate therapy, and methotrexate therapy was associated with an earlier increase in insulin requirements.

Childhood systemic lupus erythematosus and neonatal lupus syndrome.

Systemic lupus erythematosus in children can present with a wide spectrum of disease manifestations. Significant organ system involvement appears to be more severe in children than in adults. Central nervous system disease continues to be difficult to diagnose because of the lack of sensitive and specific diagnostic tests. Renal function is the major determinant of long-term prognosis and management in children with lupus. Identification of patients who are most at risk for progression of renal disease and aggressive treatment, including corticosteroids and immunosuppressive agents, are indicated. Genetic susceptibility studies in lupus reveal multiple contributions from HLA and non-HLA genes. Current concepts regarding apoptosis and DNA-protein complexes and autoreactive T-cell help for anti-DNA antibody production suggest novel directions for therapies. New understandings of the pathogenesis of neonatal lupus syndrome and congenital heart block reveals important information about prospective monitoring and management of mothers and fetuses at risk.

Decreased IL-4 production in new onset type I insulin-dependent diabetes mellitus.

IL-4 has been shown to protect against diabetes development in rodent models of insulin-dependent (type I) diabetes mellitus (IDDM). To study IL-4 production in human IDDM, PBMC from IDDM patients and controls were stimulated in vitro with PHA, anti-CD3 mAb, or PMA and ionophore. IL-4 production by PBMC or T cells was strongly impaired in IDDM patients at diabetes onset (p < 0.0001). The mean IL-4 response of patients in the honeymoon stage was higher than the mean of the new onset patients, but significantly lower than the control group (p = 0.01). Patients with IDDM of longer duration (>2 yr) showed a wide range of IL-4 responses and their mean IL-4 response was lower than the controls; however, the difference was not statistically significant. IL-4 mRNA levels were measured using competitive reverse transcription PCR. The results showed greatly reduced mRNA levels in new onset IDDM. In contrast, IL-1 production (measured by ELISA) and IFN-gamma mRNA (measured by reverse transcription PCR) were not significantly different in IDDM. The results suggest an imbalance of inflammatory vs anti-inflammatory cytokine production at the onset of IDDM. Deficient IL-4 production as seen at the onset of IDDM may play a role in the development of diabetes by allowing the inflammatory/autoimmune process in pancreatic islets to progress.

IL-4 expression in human T cells is selectively inhibited by IL-1 alpha and IL-1 beta.

Imbalances in anti-inflammatory and proinflammatory cytokines may be responsible for initiation or progression of diverse pathologic states including autoimmune and infectious diseases. IL-4 production of proinflammatory cytokines and IL-12 promotes differentiation and activation of IFN-gamma-producing T cells, but does a counter-regulatory effect of proinflammatory cytokines on IL-4 production exist? This study evaluates the effect of proinflammatory cytokines (IL-1 alpha, IL-1 beta, IL-6, IL-12, and TNF-alpha) on IL-4 production in primary human T cell cultures. PBMCs from healthy individuals were tested for IL-4 production in response to PHA and various cytokines. IL-4 was measured by proliferation of the IL-4-sensitive T cell line (CT.h4S) or ELISA. IL-1 alpha and IL-1 beta inhibited IL-4 production by 20 to 80% in > 92% of healthy individuals (p = 0.0001, paired t-test). IL-12 had an inhibitory effect on PBMC IL-4 production as previously described, but neither IL-6 nor TNF-alpha inhibited IL-4 production. IL-1 had no effect on PHA-induced PBMC or purified T cell proliferation or IL-2 production. IL-4 production by purified T cells stimulated by PHA or the combination of PMA with calcium ionophore (A23187) was inhibited by IL-1, and reconstitution with peripheral blood-derived adherent macrophages had no effect. IL-12 did not inhibit IL-4 production in stimulated purified T cells. Steady state IL-4 mRNA levels were determined by semiquantitative competitive reverse transcribed PCR (RT-PCR). Marked inhibition of IL-4 mRNA levels were seen at 5 h after exposure to IL-1. This interaction between IL-1 and IL-4 may be an important physiologic regulator of the balance between proinflammatory cytokines from activated macrophages and anti-inflammatory cytokines from T cells.

HIV type 1 induction of interleukin 1 and 6 production by human thymic cells.

In vitro and in vivo studies have demonstrated that HIV can infect thymocytes at different maturational stages and lead to changes in the thymic microenvironment. To determine the effect of HIV on thymic stromal cells and the production of cytokines important in thymocyte development, three types of adherent thymic cultures were established and studied: thymic epithelial cells (TECs), macrophage-enriched, and mixed cultures of macrophages and TECs (M phi/TEC). Cultures were exposed to HIV-1 strains HIV-1IIIB and HIV-1Ba-L, and studied from day 2 to day 26 for the presence of infection, cytopathology, and cytokine (IL-1 alpha, IL-1 beta, and IL-6) production. M phi/TEC and macrophage-enriched cultures were infected by both HIV strains without cytopathic changes. The TECs grew well in culture for at least 6 weeks and showed no evidence of infection, cytopathology, or changes in cytokine production with HIV. Only cultures containing macrophages (M phi/TEC or macrophage enriched) showed changes in cytokine production with HIV. Sustained production of IL-1 alpha was seen for up to 20 days, with small or no increases in IL-1 beta. M phi/TEC cultures produced high constitutive levels of IL-6 that were not changed by HIV. Unstimulated macrophage-enriched cultures produced small amounts of IL-6 that were increased by HIV 20-fold. This study suggests that HIV infection in vivo can lead to infection of thymic macrophages resulting in cytokine abnormalities and a constant source for HIV to infect maturing thymocytes. These cytokine effects could lead to abnormal maturation and contribute to the lack of regeneration of the mature CD4+ T cell pool.

HIV-1 infection of macrophages promotes long-term survival and sustained release of interleukins 1 alpha and 6.

HIV infection of macrophages in vivo may result in activation of monokine genes and cause persistent release of immunomodulatory and inflammatory cytokines. Studies that have examined cytokine (IL-1, IL-6, and TNF-alpha) activation by in vitro infection of normal peripheral blood mononuclear cells (PBMCs) with HIV-1 have produced conflicting results. The present study shows that for monokine induction by HIV-1-IIIB preparations derived from the H9 tumor cell line, partial purification of virus particles is essential. Infectious HIV-1 induces the release of high levels of IL-1 alpha, IL-1 beta, and IL-6 bioactivity by adherent PBMCs in the first 3 days following in vitro infection, but only IL-1 alpha and IL-6 continue to be released over several weeks of culture. High levels of bioactive IL-1 beta were released only up to 72 hr following infection, although intracellular IL-1 beta was detectable for at least 3 weeks. No TNF-alpha bioactivity or immunoreactive protein was detectable at > 48 hr in HIV-infected cultures. This time course of monokine release was dependent on the number of infectious particles added to PBMC cultures. In long-term cultures (> 1 month) HIV infection was found to promote the viability of macrophages. The finding of sustained release of IL-1 alpha and IL-6 by infected macrophages, without additional stimulation, suggests that these mediators are released by HIV-1-infected macrophages in AIDS patients, where they may interfere with proper immune regulation.

Interleukin-1 and a 7-kDa T-cell inhibitory monokine reflect disease activity in infection with HIV-1.

Previous studies demonstrated that cultured peripheral blood mononuclear cells (PBMC) from patients with AIDS produce high levels of interleukin 1 (IL-1) and a 7-kDa T-cell inhibitory monokine (TCIM). To determine if the increase in the production of these cytokines corresponded with disease activity, we studied the production of IL-1 and TCIM by PBMC from patients with different stages of human immunodeficiency virus (HIV) infection. Eight patients with asymptomatic seropositive infection, three patients with AIDS-related complex (ARC), three patients with persistent generalized lymphadenopathy (PGL), and six patients meeting the full criteria for diagnosis of AIDS were studied. Patients with AIDS produced increased amounts of TCIM (4.1 times control values, p less than 0.003) and IL-1 (2.0 times control values, p less than 0.05). In contrast, asymptomatic seropositive patients produced less TCIM (0.36 times control values, p less than 0.004) and IL-1 (0.61 times control values, p less than 0.05). Different trends in the levels of these factors produced by patients with ARC and PGL were noted, although results were not statistically significant in general. Patients with ARC tended to produce less IL-1 (0.42 times control values, p less than 0.05), whereas patients with PGL tended to produce increased amounts of IL-1 (1.7 times control values, NS). ARC patients produced a wide range of TCIM values (0.05-2.8 times control values, NS), and patients with PGL tended to produce increased TCIM values, (4.0 times control values, p less than 0.02). No correlations between the levels of IL-1 or TCIM and T-cell subpopulation numbers (CD4 or CD8) or CD4/CD8 ratios were found.(ABSTRACT TRUNCATED AT 250 WORDS)

Modulation of IL-1 alpha, IL-1 beta, and 25K Mr non-IL-1 activity released by human mononuclear cells.

To determine if the release of IL-1 alpha and IL-1 beta by cultured PBMC could be independently modulated by different exogenous stimuli, we examined the effect of LPS, IFN gamma, latex beads, and indomethacin on the release of IL-1 alpha and IL-1 beta. PBMC culture supernatants were fractionated by Sephacryl-S-200 column chromatography or HPLC (TSK G3000SW), and each fraction was tested for thymocyte mitogenic activity in the presence or absence of preincubation with anti-IL-1 alpha or anti IL-1 beta monoclonal antibody (mAb) and for the presence of IL-1 alpha or IL-1 beta protein by ELISA. In all experiments, thymocyte mitogenic activity not neutralizable by anti-IL-1 alpha or anti-IL-1 beta mAb was detected in the 25K Mr range, which ranged from 12 to 50% of the total thymocyte mitogenic activity released, depending on the stimuli. Cultured PBMC from 95% of individuals release thymocyte mitogenic activity in the absence of exogenous stimuli, which was increased 1.3-to 7-fold by lopopolysaccharide (LPS) (25-50 micrograms/ml). All of this increased activity was due to increased release of IL-1 beta and non-IL-1 thymocyte mitogenic activity, with no change in the total amount of IL-1 alpha released. Indomethacin (0.1 microgram/ml) induced release of increased thymocyte mitogenic activity of 1.3- to 1.4-fold over unstimulated cultures. All of this increased activity was due to increased release of IL-1 alpha and non-IL-1 activity with a concomitant decrease in IL-1 beta release. Interferon gamma (40-100 U/ml) increased the amount of IL-1 alpha and decreased IL-1 beta and non-IL-1 activity released, resulting in no overall change in the total amount of thymocyte mitogenic activity. Molecular weight fractionation of the PBMC culture supernatants revealed that thymocyte mitogenic activity eluting in the 25K Mr range was not due to IL-1 alpha or IL-1 beta. With certain culture conditions, thymocyte mitogenic activity was detected in the 30-40K Mr range. PBMC cultured with LPS and latex beads in the absence of serum released 30-40K Mr IL-1 alpha, as well as 17K Mr IL-1 alpha and 17K Mr IL-1 beta. PBMC cultured in 2% fetal calf serum (FCS) alone from some donors released only 30-40K Mr thymocyte mitogenic activity. Both IL-1 alpha and IL-1 beta protein was detected by ELISA in this Mr range but only the IL-1 alpha was bioactive.(ABSTRACT TRUNCATED AT 250 WORDS)

Changes in circulating monocytes in patients with progressive systemic sclerosis.

Circulating monocytes in 30 patients with progressive systemic sclerosis (PSS, scleroderma) and 28 age and sex matched normal controls were studied. Binding of the lectin peanut agglutinin (PA) was significantly reduced in PSS monocytes (p less than 0.001) together with a reduction in the density of nonspecific esterase staining (p less than 0.001) suggesting advanced maturation. Using monoclonal antibodies to identify cell surface markers, we demonstrated a significant reduction in PSS monocytes bearing the Leu M2 antigen (Mac 120, antigen presenting cells) over controls (p less than 0.05), but were unable to show any differences in the monocyte subpopulations using antisera against Leu M3 and HLA-DR surface antigens. The ectoenzymes 5'-nucleotidase (5'N) and alkaline phosphodiesterase 1 (APD1) were lower and leucine aminopeptidase (LAP) levels were higher in patients with PSS, compatible with immune activation. Interferon-gamma levels in serum did not appear to account for these changes, whereas the levels of Clq binding complexes correlated inversely with the levels of LAP (p less than 0.05). There was a strong correlation between the number of Leu M3 positive cells and the level of the ectoenzyme LAP (p less than 0.001). With increasing disease duration, higher levels of Clq binding complexes were detected (p less than 0.05). These results indicate that monocytes in PSS differ from those in normals and appear to have undergone advanced differentiation and activation changes.

Interleukin 1 inhibitor masks high interleukin 1 production in acquired immunodeficiency syndrome (AIDS).

Monocyte functions, including interleukin 1 (IL-1) production, have been shown previously to be impaired in acquired immunodeficiency syndrome (AIDS). We have fractionated culture supernatants from unstimulated peripheral blood mononuclear cells (PBMCs) to determine whether the low IL-1 activity in AIDS was due to the presence of IL-1 inhibitors. The results demonstrate that PBMCs from patients with AIDS produce increased amounts of IL-1 activity compared with those of controls together with marked increases (10- to 20-fold) in the amounts of 50,000-100,000 and 6000-9000 molecular weight (MW) factors which inhibit IL-1 activity. These inhibitors mask IL-1 activity measured in the standard thymocyte proliferation assay for IL-1. The 6000-9000 MW IL-1 inhibitor shows the greatest increase in all AIDS patients (n = 5) compared with that of controls (n = 7). This inhibitor may block the IL-1 dependent maturation of T lymphocytes in AIDS and thereby contribute to the immunodeficiency.

Increased production of an interleukin 1 (IL-1) inhibitor with fibroblast stimulating activity by mononuclear cells from patients with scleroderma.

We have previously demonstrated low IL-1 activity produced by peripheral blood mononuclear cells (PBMC) from patients with scleroderma (Sandborg et al., 1985) and the production of a 6-9 K IL-1 inhibitor by normal monocytes (Berman et al., 1986). To determine whether this inhibitor accounted for the low IL-1 activity present in scleroderma, the production of IL-1 and IL-1 inhibitor by PBMC from eight scleroderma patients was studied. Concentrated supernatants from 24 h cultures of unstimulated PBMC were fractionated on Sephacryl S-200 and tested for IL-1 and IL-1 inhibitor activity in the standard IL-1 thymocyte proliferation assay. In seven of eight patients, IL-1 inhibitor production was increased (average 3.3 X) compared to matched controls. IL-1 production was less than controls in six of eight patients. Partially purified preparations of the 6-9 K mol. wt IL-1 inhibitor were inhibitory to IL-1 induced thymocyte proliferation but stimulatory to fibroblast proliferation when purified by gel chromatography and chromatofocusing (pI 4.5-5.6). These data suggest that an IL-1 inhibitor with fibroblast stimulating activity is produced in higher amounts by PBMC from patients with scleroderma, and may contribute to the fibroblast proliferation and excessive collagen synthesis which is typical of this disease.

Studies of an interleukin 1 inhibitor: characterization and clinical significance.

Supernatants from 24 h cultures of human peripheral blood mononuclear cells (PBMNC) were fractionated and tested for interleukin (IL-1) activity in the mouse thymocyte assay with phytohaemagglutinin (PHA). By the addition of individual supernatant fractions together with partially purified IL-1 to the thymocyte assay, we demonstrate the presence of strong inhibitory activity with a mol. wt of 5,000-9,000 and an isoelectric point of 4.5-5.6. The activity is both heat (56 degrees C) and acid (pH 1.5) resistant. This inhibitor has no detectable suppressive effect on optimal and suboptimal concanavalin A (Con A), pokeweed mitogen (PWM), and PHA responses of PBMNC. The action of the inhibitor appears to be specifically directed against IL-1 action on thymocytes and has no inhibitory effect on interleukin 2 (IL-2) activity. The findings show that adherent PBMNC produce both IL-1 and a factor which opposes IL-1 action on thymocytes but not on peripheral (mature) T cells. This factor may regulate T cell maturation, activation, and proliferation.

Interleukin-1 production by mononuclear cells from patients with scleroderma.

Interleukin-1 (IL-1) production by peripheral blood mononuclear cells (PBMC) from patients with scleroderma and healthy controls was studied. Supernatants from unstimulated PBMC cultures from 10 of 13 patients with progressive systemic sclerosis (PSS) had significantly less IL-1 activity as measured by thymocyte proliferation than controls. IL-1 activity per monocyte/macrophage in both patients and controls was 10 times greater when PBMC were cultured at 10(5) cells/ml compared to 10(6) cells/ml. Five-fold dilution of supernatants from PBMC cultured at 10(6) cells/ml revealed more IL-1 activity than undiluted supernatant and addition of indomethacin increased IL-1 activity primarily of the undiluted supernatant. The results show that IL-1 activity from crude PBMC supernatants from PSS patients is low and may be regulated by non-dialysable inhibitors produced by PBMC and/or cell interactions.