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Biomedical subjects

S C Jordan

Publications and source records attributed to S C Jordan.

At least 109 records · Page 6Linked to original sources
PubMed1988

Anti-vascular endothelial cell antibodies in patients with IgA nephropathy: frequency and clinical significance.

This study examined the frequency of anti-vascular endothelial cell (VEC) antibodies (Ab) in 72 patients with IgA nephropathy (IgAN), and their possible relationship to clinical and histological parameters of the disease. An enzyme immunoassay was developed to measure the binding of sera to endothelial cells grown to a confluent monolayer. Thirty-two percent of IgAN patients had serum anti-VEC activity as compared to 4% of controls (P = 0.004) and 9% of patients with other primary glomerulonephritis (P = 0.017). This was shown to be due to anti-HLA class I Abs in 6 of the 23 IgAN patients, and in the 1 control positive for anti-VEC activity. Hence 17 IgAN patients had anti-VEC Abs, predominantly of the IgA subclass. Stimulation of the endothelial cells with interferon-gamma and interleukin 1 did not increase the binding of these Abs. There was no correlation with circulating immune complex (IC) levels, and removal of ICs in positive sera by ultracentrifugation did not decrease anti-VEC binding. Significant correlations were found between anti-VEC Abs and proteinuria greater than 1 g/day (P = 0.044), as well as IgA anti-VEC Abs and C3 or IgA deposition in renal arterioles (P = 0.048). These IgA Abs may be an important marker of pathogenetic activity in IgAN.

Adolescent↗
PubMed1988

Interleukin-2 receptor expression in peripheral blood lymphocytes from systemic lupus erythematosus patients: relationship to clinical activity.

Deficient interleukin-2 (IL-2) production and other T-cell dysfunctions have been demonstrated in active systemic lupus erythematosus (SLE). The generation of IL-2 receptors is known to be important to the growth and differentiation of T and B lymphocytes. This study investigated IL-2 receptor expression in peripheral blood lymphocytes (PBL) from patients with active and inactive SLE. PBL from 27 SLE patients, diagnosed by revised ARA criteria, were assayed for IL-2 receptor expression, IL-2 and immunoglobulin (Ig) production. PBL from SLE patients with active disease spontaneously expressed increased numbers of IL-2 receptors compared to those with inactive disease (P less than 0.01) and normal donors (P less than 0.01). There was no significant increase in IL-2 receptors expression in PBL from active SLE patients in response to mitogenic stimulation with PHA compared to inactive SLE patients and normal donors. There was negligible IL-2 production in response to mitogenic stimulation and increased spontaneous IgG production by PBL from active SLE patients compared to normal donors (P less than 0.001). Purified B cells isolated from active SLE patients showed significant spontaneous IL-2 receptor expression when compared to spontaneous IL-2 receptor expression by normal B cells (P = 0.005). Therefore, in addition to derangements in Ig and IL-2 production, the level of spontaneous expression of IL-2 receptors may represent a cellular indicator of disease activity, and hence, may be a useful parameter in monitoring disease activity in SLE patients. The significance of the increased IL-2 receptor expression on B cells of active SLE patients is unknown, but may represent a marker of polyclonal activation of these cells.

Antibody Formation↗
PubMed1987

Plasma exchange improves the glomerulonephritis of systemic lupus erythematosus in selected pediatric patients.

The effects of short-course plasma exchange (PE) followed by tapering dose prednisone therapy was assessed in six children with systemic lupus erythematosus (SLE) and severe glomerulonephritis. All patients received pulse methylprednisolone therapy and three patients were treated with cytotoxic drugs prior to PE, but none had exhibited a good response. PE resulted in a rapid and sustained (greater than 1 year) remission of renal failure in the three patients with renal failure and severe glomerulonephritis. All six patients had severe nephrotic syndrome and five of six experienced a complete and sustained (greater than 1 year) remission post-PE (the sixth patient has greater than 4 month remission at the time of writing). Of interest was the high frequency of membranous [World Health Organization (WHO) Type V] and mixed membranous and diffuse proliferative SLE nephritis (WHO Type IV) on renal biopsy (4/6 patients). In addition, the severe anemia and leukopenia seen in most patients responded favorably to PE. Five of the six patients are currently managed on low-dose prednisone (0.25-0.5 mg/kg) every other day. One patient progressed to renal failure and dialysis more than 1 year post-PE. One patient required cytotoxic drug therapy post-PE (6 weeks). No significant complications were encountered; in fact, all patients eventually received their PE treatments as outpatients. We conclude that PE may provide a safe and effective therapeutic option for the treatment of severe progressive SLE nephritis in selected children who are unresponsive to steroid or cytotoxic drug therapy.

Adolescent↗
PubMed1987

Detection of bovine serum albumin in the circulating IgA immune complexes of patients with IgA nephropathy.

Alimentary antigenic challenge has been postulated to have a role in the genesis of IgA circulating immune complexes (CIC), resulting in mesangial IgA disease. In this study, we examined the relationship between bovine serum albumin (BSA) and IgA CIC in patients with IgA nephropathy. Of the 47 patients studied, elevated IgA CIC levels were found in 32% by the F(ab')2 anti-C3 and Raji cell enzyme immunoassays (EIA). Elevated IgA anti-BSA antibody levels were found in 9 patients, and there was a positive correlation between these levels and IgA CIC as measured in the Raji cell EIA (R = 0.60, P less than 0.001). In 4 patients with elevation of both IgA CIC and IgA anti-BSA antibody levels, solubilization experiments were done to demonstrate the presence of BSA antigen in the IgA CIC. Using the Raji cell EIA, the IgA CIC levels decreased significantly after preincubating the sera with serial concentrations of excess BSA. No corresponding effect was seen with human serum albumin used as control. Hence, BSA may be the antigenic stimulus in the formation of IgA CIC in selected patients with IgA nephropathy. The pathogenic capacity of these IgA-BSA CIC remains to be determined.

Adolescent↗
PubMed1987

Serositis with autoimmune endocrinopathy: clinical and immunogenetic features.

Twenty patients with autoimmune endocrinopathies experienced 45 episodes of pleural and/or pericardial serositis. Seventeen of these patients were women and 15 had clinical or serologic evidence of 2 or more endocrinopathies. Idiopathic primary hypoadrenalism (10 cases), Graves' disease (8 cases), Hashimoto's disease (4 cases), atrophic thyroiditis with hypothyroidism (3 cases), idiopathic primary hypogonadism (3 cases), transient thyroiditides (2 cases), and type I diabetes mellitus (1 case) were diagnosed at a mean age of 24 years. Serositis recurred after asymptomatic intervals of months to years even in patients treated for endocrine dysfunction. Fourteen of 16 Caucasians had circulating immune complexes, including all 9 patients with a C4AQ0 (C4A null) phenotype and including all 12 patients with HLA antigens B8 and DR3, antigens associated with systemic lupus and with autoimmune endocrinopathies. Serositides associated with autoimmune endocrinopathies can occur with chest pain, fever, and exudative effusions in young Caucasian women with the HLA B8 DR3 C4AQ0 phenotype. These serositides may have a common pathophysiologic mechanism.

Adolescent↗
PubMed1987

Determination of antiidiotypic antibodies to anti-HLA IgG following blood transfusions.

Blood transfusions (BT) administered prior to renal allograft transplantation are known to enhance allograft survival. One proposed mechanism for this effect is through the induction of antiidiotypic antibodies that modify the immune response to subsequently presented graft antigens. In an attempt to determine if antiidiotypic antibodies are generated post-BT, we studied sera from post-BT patients for the presence of antiidiotypic antibodies to anti-HLA class I IgG (i.e., anti-anti-HLA). Anti-HLA antiidiotypes were demonstrated by idiotype-specific inhibition of an enzyme immunoassay (EIA) for anti-HLA antibodies. Using this inhibition technique, test sera from 8 of 16 post-BT patients showed significant inhibition of the anti-HLA target sera (P less than 0.05). Sera from normal individuals showed no inhibition of the target sera, and test sera did not inhibit other antigen-antibody systems. Protein A absorption of test sera eliminated the inhibitory effect, suggesting that the antiidiotypic activity was limited to the IgG fraction of the sera. The EIA binding activity of F(ab')2 fragments of anti-HLA IgG was suppressed by sera from patients post-BT but not by sera from normal volunteers. Studies of serially obtained sera from a post-BT patient showed that anti-HLA antiidiotype levels fluctuate with time and transfusion status. These studies demonstrate that anti-HLA antiidiotypic antibodies are generated post-BT. Their importance in mediating the known allograft-enhancing effect of pretransplant BT remains to be clarified.

Antibodies, Anti-Idiotypic↗
PubMed1986

Amiloride inhibition of DNA synthesis and immunoglobulin production by activated human peripheral blood mononuclear cells is independent of sodium/hydrogen antiport.

Activation of sodium/proton (Na+/H+) antiport activity has been shown to occur as an early event in mitogenesis. Because amiloride inhibits Na+/H+ antiport activity, it is hypothesized that mitogenesis may be inhibited by amiloride. In this work, we examined the effect of amiloride on DNA synthesis as measured by [3H]thymidine uptake and immunoglobulin (Ig) production as measured by an ELISA system in human peripheral blood mononuclear cells (PBM). Amiloride at 100 microM concentration inhibited irradiated Raji cell (*R)-activated and phytohemagglutinin-P (PHA-P)-stimulated DNA synthesis by 50 +/- 11% and 72 +/- 12%, respectively. IgG production was inhibited by 71% at 100 microM amiloride concentration in *R-activated PBM. This concentration of amiloride inhibited Na+/H+ antiport activity by 92%. Because amiloride is known to inhibit other pre-replicative cellular functions such as protein synthesis, we used an amiloride analogue, dimethylamiloride, which inhibited Na+/H+ antiport activity by 90% at a concentration of 1 microM without inhibition of PBM Ig or DNA synthesis. Furthermore, neither PHA-P nor *R-stimulated PBM demonstrated an intracellular alkalinization even after 6 hr of stimulation. Similarly, T cell-enriched or B cell-enriched populations did not show intracellular alkalinization after PHA-P or *R activation. Thus, it appears that Na+/H+ antiport activation is not an early event in PBM mitogenesis. The inhibition of mitogenesis by amiloride may be due to abrogation of premitotic events such as protein synthesis.

Adult↗
PubMed1986

Superior vena caval abnormalities: their occurrence rate, associated cardiac abnormalities and angiographic classification in a paediatric population with congenital heart disease.

Angiography of the superior systemic veins was performed on 510 patients with congenital heart disease. An analysis of these angiograms was carried out and a simple angiographic classification of superior vena caval anomalies is presented. Eleven per cent of cases had complete bilateral superior vena cavae, a frequency of occurrence higher than that previously reported. An analysis of associated congenital heart lesions revealed a higher than average association of bilateral superior vena cavae with atrioventricular septal defects and double-outlet right ventricle, but this was seen rarely in cases of transposition of the great arteries. Bilateral superior vena cavae also occurred very frequently (72%) in patients with situs abnormalities. Femoral vein catheterisation is likely to facilitate diagnosis and appropriate radiological signs are discussed.

Adolescent↗
PubMed1986

Experience with renal transplantation in children undergoing peritoneal dialysis (CAPD/CCPD).

For children with end-stage renal disease, renal transplantation is the ultimate goal because it offers the potential of maximum rehabilitation. In order to evaluate the infectious risk of renal transplantation in patients previously maintained on continuous ambulatory peritoneal dialysis (CAPD) and/or continuous cycling peritoneal dialysis (CCPD), we retrospectively evalauted the clinical course of 44 pediatric patients (mean age 12.0 +/- 5.7 [SD] years) who received 32 cadaver and 16 live-related donor renal grafts after being maintained on peritoneal dialysis for 756 patient-months (mean 17.1 +/- 11.5 months). In the posttransplant period, 25 patients (57%) required dialysis because of acute tubular necrosis or acute rejection. Peritonitis developed in five patients (11%) following transplantation; two were being dialyzed at the time. Exit-site and tunnel infections occurred in nine patients (20%). In all instances, antibiotic treatment and/or catheter removal was curative. Posttransplant ascites developed in 12 patients (27%) and was alleviated by catheter drainage. The catheters were left in situ at the time of transplantation and electively removed when stable graft function was present. The 1- and 2-year actuarial graft survival rate was 65% and 55%, respectively. One patient died in the immediate posttransplant period, which was unrelated to peritoneal dialysis. In conclusion, pediatric patients maintained on CAPD and/or CCPD can be safely transplanted. The potential infectious risks related to peritoneal dialysis can be managed with appropriate management of the catheter and prompt antibiotic therapy. The patient and graft survival rates are comparable to those with patients receiving hemodialysis prior to transplantation. There is no need to limit access to transplantation in children undergoing CAPD and/or CCPD.

Adolescent↗
PubMed1986

Spontaneous anti-tubular-basement-membrane antibody production by lymphocytes isolated from a rejected allograft.

The immunological events mediated by, and antigen specificity of, allograft-bound lymphocytes (ABLs) are poorly understood. To further define the role of antibody-mediated rejection, a rejected allograft from a patient with primary anti-TBM disease was sterilely minced and pressed through a microscreen. The ABLs were isolated by density gradient centrifugation. Using this technique, 8.5 X 10(6) ABLs were isolated. Then 1 X 10(6) washed ABLs/ml were suspended in RPMI 1640 with 20% fetal calf serum and cultured in microtiter plates with media only, or with pokeweed mitogen (PWM) (100 micrograms/culture). The cells were incubated for 7 days and supernatants were collected and assayed for total IgG and IgM by a solid-phase enzyme immunoassay (EIA) and reactivity with normal human kidney targets by indirect immunofluorescence (IF) and immunoperoxidase (IP) techniques. Total IgG production was 500 ng/ml for both spontaneous and PWM stimulated cells. No IgM production was detected. IF and IP studies demonstrated IgG-anti-TBM antibodies in the spontaneous supernatants only. IgG antibodies reactive with peritubular capillaries (anti-PTC) were also noted. IgG-anti-TBM anti-bodies and antibodies reactive with arterioles were subsequently demonstrated by direct immunofluorescence techniques in the rejected allograft. Analysis of serum samples obtained at the time of allograft rejection showed no IF or IP reactivity with the kidney targets. Subsequent analysis of anti-TBM production by the patient's peripheral blood mononuclear cells (PBMs) showed IgM-anti-TBM only. These studies suggest that the IgG-anti-TBM and IgG-anti-PTC antibodies reactive with the allograft resulted from in situ antibody production by ABLs; the role of anti-TBM antibodies in mediating the AR is unclear, but their presence suggests recurrence of the original disease in the allograft. Anti-PTC antibodies could be important in mediation of the vascular AR.

Adolescent↗
PubMed1986

Postpartum renal failure in a patient with membranoproliferative glomerulonephritis type II.

The previously reported detrimental effects of pregnancy on the course of membranoproliferative glomerulonephritis type II (MPGN type II) are limited and are usually considered to be mild. Based on these reports, a 19-year-old female with the diagnosis of MPGN type II who had stable renal function (creatinine 0.9 mg/dl) and a mild nephrotic syndrome with hypertension for 5 years of close follow-up was advised to complete her pregnancy. After a full-term pregnancy, complicated only by moderate nephrotic syndrome, a healthy female infant was born. Two weeks after delivery, the patient presented with acute renal failure and malignant hypertension, without evidence of hemolysis of hepatic failure. Immunologic parameters, including, C3, C4, antinuclear antibodies, circulating immune complexes as well as antibodies to glomerular basement membrane antigen and tubular basement membrane antigen were negative. Peritoneal dialysis was initiated and a renal biopsy was performed which showed MPGN type II with 50% crescents. Despite pulse therapy with methylprednisolone, renal function did not improve, resulting in the need for chronic dialysis. Although no specific nephritogenic mechanism was shown, the course of this patient should be considered when counseling female patients with MPGN type II, regarding the possibility of pregnancy exacerbating their disease, or resulting in rapidly progressive renal failure.

Acute Kidney Injury↗
PubMed1985

Quantitation of circulating immune complexes in human serum by the Raji cell and F(ab')2 anti-C3 micro enzyme immunoassays.

Two micro enzyme immunoassays (microEIA) for circulating immune complexes (CICs) are described. The Raji cell microEIA was similar in sensitivity, reproducibility and specificity to the Raji radioimmunoassay. The F(ab')2 anti-C3 microEIA was comparable to the 2 Raji cell assays. The 2 microEIAs for CICs were used to analyze sera from patients with systemic lupus erythematosus (SLE), the acquired immune deficiency syndrome (AIDS) and from hemophiliacs with AIDS-like symptoms. The microEIAs were very sensitive in detecting CICs in pathologic sera. In contrast, only 3% of normals (n = 30) were positive in the Raji microEIA while none were positive in the F(ab')2 anti-C3 microEIA. The initial high positivity of some normals (9/30) in the F(ab')2 microEIA was due to bovine serum albumin (BSA)-anti-BSA immune complex formation in vitro and was corrected when human albumin was used in buffer preparation instead of BSA. The reagents required for the microEIAs are more stable and less expensive than those required for the RIAs and the need for facilities to deal with 125-labeling and disposal is avoided.

Acquired Immunodeficiency Syndrome↗