Raised serum levels of cachectin/tumor necrosis factor alpha in renal allograft rejection.

A sensitive radioimmunoassay was used for monitoring serum levels of endogenous cachectin/tumor necrosis factor alpha (TNF) in 10 renal transplant recipients. Acute allograft rejections were associated with marked elevations of circulating TNF. The peak levels of TNF (median 140 pg/ml) were in the same concentration range as previously reported in parasitic infections. The results show that the release of TNF into circulation is an early event in renal allograft rejection and that raised levels of TNF in man can also be induced by noninfectious stimuli.

Pioglitazone has anti-inflammatory effects in patients with Type 2 diabetes.

BACKGROUND: Type 2 diabetes is characterized by increased acute phase serum proteins. They are also risk factors for cardiovascular disease. We wanted to study how improvement of glycemic control with pioglitazone or glibenclamide affects their serum concentrations. MATERIALS AND METHODS: A total of 59 patients with Type 2 diabetes (age 57.3+/-1.2 yr, glycosylated hemoglobin (HbA1c) 8.3+/-0.7%, body mass index (BMI) 31.4+/-0.8 kg/m2) participated in the study. They were previously treated either with diet alone or in combination with one oral antihyperglycemic medicine. After a 1-week lead-in period on diet only, the patients were randomized to pioglitazone or glibenclamide. Blood samples for alpha-1-acid glycoprotein (A1GP), Creactive protein (CR P) and serum amyloid A (SAA) were taken before the treatments and during the therapy after 20 and 52 weeks. RESULTS: Baseline A1GP correlated with CR P (r=0.70, p<0.001) and fasting glucose (r=0.32, p<0.02). Baseline CR P correlated with HbA1c (r=0.26, p<0.05) and insulin (r=0.37, p<0.01). The anti-hyperglycemic effect was comparable with HbA1c levels decreasing both in the pioglitazone (from 8.18+/-0.09% to 7.63+/-0.17%, p<0.01) and glibenclamide (from 8.35+/-0.12% to 7.77+/-0.16%, p<0.01) groups. Pioglitazone treatment was associated with a reduction in A1GP at 20 weeks (p<0.001) and at 52 weeks (p<0.05) as compared to baseline. The significance remained also after comparison to glibenclamide therapy (p<0.001 and p<0.05, 20 and 52 weeks respectively). CR P was also more reduced in the pioglitazone group at 20 weeks of treatment (p<0.05). CONCLUSIONS: Inflammatory factors and markers of hyperglycemia are associated in patients with Type 2 diabetes. Pioglitazone treatment results in reduced A1GP concentration suggesting an anti-inflammatory effect.

Improved glycaemia in type 1 diabetes results in decreased levels of soluble adhesion molecules with no change in serum adiponectin or most acute phase proteins.

AIMS: To investigate how reduction of hyperglycaemia affects acute phase serum proteins in poorly controlled type 1 diabetic patients. METHODS: 24 patients (age 31.7 +/- 2.0 years, HbA1c 9.3 +/- 0.2%, BMI 24.2 +/- 0.7 kg/m2, diabetes duration 15.3 +/- 1.7 years) participated in the study. The treatment was optimised for 16 weeks. Blood samples were taken at baseline and at the end of the study. 16 healthy age- and BMI-matched subjects were chosen for a control group. RESULTS: At baseline, the patients had higher C-reactive protein (CRP) (1.09, median [range 0.24-18.82] mg/l vs. 0.66 [0.18-2.46] mg/l, p < 0.02), mean adiponectin (16.06 +/- 1.31 vs. 8.85 +/- 0.93 mg/l, p < 0.001), ceruloplasmin (306 +/- 16.1 vs. 205.4 +/- 5.5 mg/l, p < 0.001), fibrinogen (3.41 +/- 0.26 vs. 2.38 +/- 0.07 g/l, p < 0.001), soluble intercellular adhesion molecule-1 (sICAM-1) (255.4 +/- 10.3 vs. 194 +/- 10.6 microg/l, p < 0.001), soluble vascular adhesion molecule-1 (sVCAM-1) (533.4 +/- 21.8 vs. 422.9 +/- 20.7 microg/l, p < 0.01) and interleukin-6 (2.89 +/- 0.49 vs. 1.35 +/- 0.30 ng/l, p < 0.01) concentrations than the controls. During intensified treatment, HbA1c decreased (to 8.5 +/- 0.2%, p < 0.001). This resulted in reduced sE-selectin (from 44.6 +/- 2.6 to 38.8 +/- 2.6 microg/l, p < 0.01), alpha-1-acid-glycoprotein (A1GP) (from 622.9 +/- 47.9 to 525.7 +/- 27.9 mg/l, p < 0.01), sICAM-1 (from 255.4 +/- 10.3 to 240.8 +/- 9.1 microg/l, p < 0.05) and IL-6 (from 2.9 +/- 0.5 to 2.1 +/- 0.4 ng/l, p < 0.01). Serum amyloid A (SAA) and CRP did not change 12.00 (0.7-222.0) vs. 12.00 (1.6-277.0) mg/l for SAA and 1.09 (0.24-18.82) vs. 1.09 (0.18-23.08) mg/l for CRP, baseline vs. treatment, respectively. CONCLUSIONS: Poorly controlled type 1 diabetic patients have increased values of adiponectin, CRP, ceruloplasmin, fibrinogen, sICAM-1, sVCAM-1 and IL-6. Reduction of hyperglycaemia results in decreased sE-selectin, A1GP, sICAM-1 and IL6, while other inflammatory factors including CRP, SAA and adiponectin are not affected.

Magnetic resonance imaging findings in Finnish Spitz dogs with focal epilepsy.

Eleven Finnish Spitz dogs with focal seizures and 3 healthy controls were evaluated. General clinical and neurological examinations, blood examination, urinalysis, cerebrospinal fluid examination, electroencephalography (EEG), and magnetic resonance imaging (MRI) of the brain were performed on all dogs. On EEG examination, focal epileptic activity was found in 7 of 11 dogs (64%), and generalized epileptic activity was observed in 4 of 11 dogs (36%). MRI (performed with 1.5 T equipment) detected changes in 1 epileptic dog. Mild contrast enhancement after gadolinium injection was identified in this dog's right parietal cortex. However, no such changes were observed in repeated magnetic resonance images. Special emphasis was given to seizure history to determine any correlations between seizure intervals and MRI findings. Our results indicate that Finnish Spitz dogs with focal seizures suffer from focal idiopathic epilepsy and have nondetectable findings on MRI or pathology. MRI showed poor sensitivity in detecting epileptogenic areas in our patients with focal seizures. Reversible MRI changes in 1 dog could have been caused by seizures.

Tumor necrosis factor in children with malignancies.

We measured serum tumor necrosis factor alpha (TNF) concentrations by a double-antibody radioimmunoassay method, with a detection level of 10 ng/liter, in 32 children with malignancies. Seventeen had acute lymphoblastic leukemia, 4 had acute nonlymphocytic leukemia, and 11 had solid tumors. At the diagnosis of malignant disease, 30 of the 32 patients had elevated serum TNF levels ranging up to 450 ng/liter. After complete remission status was achieved, 2-6 months from the diagnosis, the TNF levels were within the range of 130 healthy children who served as the reference group. Most of them had TNF levels below the detection limit. We consider the upper limit of normal to be 40 ng/liter. We conclude that elevated serum TNF concentration may be of potential significance in the diagnosis and follow-up of children with malignant diseases.

Urinary excretion of plasma proteins in diabetic subjects. Increased excretion of kappa light chains in diabetic patients with and without proliferative retinopathy.

The urinary excretion of beta2-microglobulin, albumin, kappa light chains, transferrin, and IgG as well as their concentration ratios were assessed in 27 nondiabetic patients with proteinuria and in 72 IDDM patients, 41 with proliferative retinopathy (PR) and 31 without retinopathy, matched for age, duration of diabetes, and treatment. The mean excretions of albumin, transferrin, and IgG were similar in patients with nondiabetic proteinuria and in IDDM patients with PR and were significantly higher than in IDDM patients without retinopathy. Despite similar albumin excretion, the amount of excreted kappa light chains was significantly higher in IDDM patients than in patients with nondiabetic proteinuria, resulting in an elevated kappa chain/albumin ratio. Furthermore, diabetic subjects without microalbuminuria showed increased kappa chain/albumin ratio, indicating that increased urinary excretion of kappa chains may be an early sign of diabetic nephropathy. Determination of kappa light chain excretion may have clinical implications in the differentiation between proteinuria of diabetic and nondiabetic origin. The ratio kappa chain/albumin was independent of the excretion of beta2-microglobulin in patients with PR, suggesting that the reduced ability to reabsorb immunoglobulin light chains may occur earlier than that of beta2-microglobulin in the development of tubular dysfunction in insulin-dependent diabetes mellitus.

No evidence of amyloidosis in type I diabetics treated with continuous subcutaneous insulin infusion.

A recent study has demonstrated secondary amyloidosis in dogs treated with continuous intravenous insulin infusion. Since elevated levels of serum amyloid A protein (SAA) and diminished amyloid fibril degrading activity (AFDA) are associated with amyloidosis, we measured SAA and AFDA in ten type I diabetics treated with continuous subcutaneous insulin infusion and in five conventionally treated patients. Only one pump- and one conventionally treated patient had detectable but low SAA levels, comparable with these seen in healthy controls. In patients with secondary amyloidosis the mean SAA level was 24-fold higher than in controls (P less than 0.001). Similarly, in both diabetic groups, AFDA was normal whereas it was reduced by 41% in patients with amyloidosis (P less than 0.001). Furthermore, no local amyloidosis was seen at the infusion site in any of the patients studied. Thus, our data fail to provide any evidence of secondary amyloidosis in patients treated for 3-40 mo with continuous subcutaneous insulin infusion.

Risk factors and markers associated with proliferative retinopathy in patients with insulin-dependent diabetes.

To define risk factors and markers associated with proliferative retinopathy (PR), we compared 44 insulin-dependent diabetic patients with PR with 45 matched patients without advanced retinopathy (NR). Glycemic control assessed by HbA1 measurements from 5 yr preceding diagnosis of PR was significantly worse than in NR patients. The NR patients had more frequently been treated with multiple daily insulin injections than the PR patients. About half of the PR patients had Albustix-positive proteinuria, and these patients were further characterized by an abnormal lipid profile in plasma and increased frequency of cardiovascular disease. In contrast, PR patients without proteinuria did not differ from NR patients in these variables. Sensorimotor and autonomic neuropathy were twice as frequent in the PR than in the NR group. There was no correlation between anti-insulin antibody titer, immune complexes, and the presence of PR, but T-lymphocyte response to different stimuli was slightly reduced in the PR patients. The anti-insulin-antibody titer correlated with duration of diabetes in the NR but not the PR group. The frequency of HLA-DRw8 was slightly higher in the PR group than in the NR group (16 vs. 0%, NS), but we could not confirm the previously suggested association between HLA-DR4 and PR. Serum C4 levels were low in the diabetics but did not differ between PR patients without proteinuria and NR patients. In conclusion, poor glycemic control was clearly associated with PR in this study, and attempts to prevent this hazardous complication should include means to improve insulin therapy. We did not find support for the view that susceptibility to PR is associated with any known HLA antigen(s).(ABSTRACT TRUNCATED AT 250 WORDS)

Urinary transforming growth factor-beta1 and alpha1-microglobulin in children and adolescents with type 1 diabetes.

OBJECTIVE: Transforming growth factor (TGF)-beta1 is an important mediator in the pathogenesis of diabetic nephropathy. Urinary TGF-beta1 reflects TGF-beta1 production in the kidney, and alpha1-microglobulin tubular dysfunction. These 2 markers were studied in the early phases of type 1 diabetes. RESEARCH DESIGN AND METHODS: There were 113 type 1 diabetic children and adolescents (mean +/- SD: age 14.1 +/- 2.9 years, and diabetes duration 7.4 +/- 2.9 years, HbA1c 9.3 +/- 1.5%) and 39 healthy subjects (age 13.8 +/- 2.8 years) who participated in the study. Of the diabetic patients, 105 were normoalbuminuric (2-3 consecutive overnight urinary albumin excretion rates [AERs] <20 microg/min) and 8 had microalbuminuria (at least 2 AERs 20-200 microg/min). Overnight urinary TGF-beta1 and alpha1-microglobulin levels were measured and the results expressed as the ratio to urinary creatinine concentration. RESULTS: Data are medians (range). Diabetic patients had higher urinary TGF-beta1 levels than those of control subjects: 0.9 ng/mg (0.05-122.3) vs. 0.3 ng/mg (0.05-2.2) creatinine, respectively (P = 0.003). Urinary TGF-beta1 levels correlated with urinary glucose (r = 0.2, P = 0.03) and alpha1-microglobulin (r = 0.2, P = 0.02) levels, but not with HbA1c, AER, age, or duration of diabetes. In 43 patients with urinary TGF-beta1 above the control levels, urinary TGF-beta1 levels correlated with urinary glucose (r = 0.6, P < 0.001) and alpha1-microglobulin (r = 0.6, P < 0.001) levels. Diabetic patients had higher urinary alpha1-microglobulin levels than those of control subjects: 4.8 microg/mg (0.6-48.8) vs. 2.7 microg/mg (0.8-11.6) creatinine, respectively (P < 0.001). Alpha1-microglobulin levels correlated with AER (r = 0.2, P = 0.02), HbA1c (r = 0.3, P = 0.001), urinary glucose (r = 0.5, P < 0.001), and urinary TGF-beta1 levels. CONCLUSIONS: An early rise in urinary TGF-beta1 levels was observed in young type 1 diabetic patients. Urinary TGF-beta1 is associated with 2 interrelated tubular markers, alpha1-microglobulin and urinary glucose.

Recurrent fever associated with progesterone action and persistently elevated serum levels of immunoreactive tumor necrosis factor-alpha and interleukin-6.

We describe two women who suffer from recurrent fever up to 40 C in association with progesterone action and who have continuously elevated serum levels of immunoreactive tumor necrosis factor-alpha (TNF alpha) and interleukin-6 (IL-6). In patient 1, recurrent fever began at age 17 yr and has now continued for 11 yr. The patient has had three early pregnancy terminations because of continuous fever and, thereafter, three early pregnancy losses associated with fever. In patient 2, fever first appeared at age 18 yr, and the attacks have now continued for 3 yr. The association between fever and progesterone action is supported by the following facts. 1) The episodes of fever appear in the midluteal phase of the menstrual cycle concomitantly with the highest concentration of serum progesterone. 2) Fever is further exaggerated in early pregnancy. 3) Synthetic progestins induce fever regardless of the day of the menstrual cycle. 4) The progesterone antagonist RU 486 and an agonist of GnRH, nafarelin, are capable of preventing the fever, with no effect on serum cytokine levels. Although the underlying mechanism of elevated TNF alpha and IL-6 levels in our patients remains unknown, the data suggest that these cytokines cooperate with progesterone in exerting a pyrogenic response in the hypothalamic thermoregulatory center.

Enzyme immunoassay of antibodies to epithelial glycoprotein: increased level of antibodies in coeliac disease.

From the papules of a patient with massive cutaneous hyalinosis, we earlier isolated a mannose-rich glycoprotein that, by immunohistochemical methods, was also shown to be present in epithelial cells of small intestine and normal skin. A solid-phase enzyme immunoassay of IgG and IgM antibodies to this epithelial glycoprotein is described, in which polystyrene tubes are coated with the purified antigen. The antibodies are allowed to bind, and are detected with alkaline phosphatase-conjugated anti-human IgG and IgM. IgG, IgA and IgM antibodies were determined in the sera of patients with pemphigus, pemphigoid, dermatitis herpetiformis, several autoimmune diseases, in a patient with massive cutaneous hyalinosis, in coeliac disease, and in control subjects. Very high values were found in the patient with massive cutaneous hyalinosis, and significantly elevated values in coeliac disease. In the other patient groups values were equal to or only slightly higher than in controls.

Elevated levels of circulating cachectin/tumor necrosis factor in patients with acquired immunodeficiency syndrome.

PURPOSE: In order to evaluate the relationship between cachectin/tumor necrosis factor (TNF) and cachexia in the acquired immunodeficiency syndrome (AIDS), we studied the serum levels of endogenous cachectin/TNF in subjects with human immunodeficiency virus (HIV) infection. PATIENTS AND METHODS: Fifty-three serum samples were obtained from 39 HIV-seropositive patients. The condition of each patient was clinically classified as either asymptomatic, lymphadenopathy syndrome (LAS), AIDS-related complex (ARC), or AIDS. Control sera were obtained from 29 healthy male blood donors. A double antibody radioimmunoassay was used to measure the serum levels of cachectin/TNF. RESULTS: Cachectin/TNF levels were within the reference range of the control values in all (eight of eight) asymptomatic HIV-infected subjects and in 11 of 13 of the patients with LAS. In contrast, all patients with AIDS (nine of nine) and five of nine of the patients with ARC had raised levels of cachectin/TNF. Fluctuation of the levels of cachectin/TNF occurred during follow-up, but initially raised levels remained elevated. CONCLUSION: Since cachectin/TNF suppresses lipoprotein lipase in adipocytes in vitro, and causes weight loss under experimental conditions, the findings of raised levels of cachectin/TNF in patients with AIDS may have relevance to the pathogenesis of cachexia.

Serum immunoreactive interleukin 1 in renal transplant recipients. Association of raised levels with graft rejection episodes.

A solid-phase radioimmunoassay was used for monitoring serum interleukin 1 levels in 12 renal transplant recipients. From 10-fold to 20-fold elevations of interleukin 1 occurred in association with 10 of 12 graft rejection episodes. The interleukin 1 elevation preceded the clinical rejection diagnosis by an average of one day in transplant recipients with initially functioning grafts, and by two days in recipients with delayed onset of graft function. The results show that the release of interleukin 1 into the circulation is an early event in renal allograft rejection and demonstrate the potential utility of interleukin 1 antigenic assays in the early diagnosis of rejection.

Changes of urinary alpha1-microglobulin in the assessment of prognosis in renal transplant recipients.

BACKGROUND: After transplantation, even if the graft starts functioning immediately, there are morphological and functional changes in tubular structures. In addition, acute allograft rejection causes damage in the tubular epithelium, tubular basement membrane, and intertubular connective tissue. It also affects the functional capacity of proximal tubular cells resulting in impaired reabsorption and thus increased urinary excretion of low molecular weight proteins. METHODS: We present a double-antibody radioimmunoassay for determination of the concentration of alpha1-microglobulin (alpha1 M) in urine. It was used to measure urinary excretion of alpha1 M approximately once a week during the first 1-6 posttransplant weeks in 136 consecutive patients: 30 patients developing acute rejection (75 24-hr urine samples) and 106 patients with stable graft function (223 24-hr urine samples). The results are expressed as alpha1 M/creatinine ratios. RESULTS: Approximately 8 days after transplantation the mean (+/-SD) urinary alpha1 M/creatinine ratio of all patients was 17.0+/-14.8 mg/mmol, being about the same both in patients with uncomplicated posttransplantation course (16.3+/-14.0 mg/mmol) and in those who later developed rejection (19.3+/-15.1 mg/mmol), but about 60-fold higher than in healthy controls (0.27+/-0.15 mg/mmol). At that time, when all patients were included there was a correlation (r=0.3465, P<0.001) between alpha1 M/creatinine ratio and duration of cold ischemia. Thereafter, during the second week alpha1 M/creatinine ratio decreased in 89% of patients with stable graft function, but only in 14% of patients who later developed rejection (P<0.001). On the contrary, a significant increase (P<0.01) of alpha1 M/creatinine ratio was observed 4 to 1 day before rejection in all 15 patients, who had urines collected at that time. At the end of the follow-up period, alpha1 M/creatinine ratio in patients with rejection was 3-fold compared with the nonrejecting patients, and 100-fold compared with the healthy controls. CONCLUSION: These results show that cadaveric transplantation results in impaired low molecular weight protein reabsorption, the degree of dysfunction relating to the duration of cold ischemia, and suggest that during the posttransplant weeks decreasing alpha1 M/creatinine ratio in consecutively collected urine samples indicates improved tubular function and in most cases rules out development of acute rejection.

Does increased urinary interleukin-1 receptor antagonist/interleukin-1beta ratio indicate good prognosis in renal transplant recipients?

BACKGROUND: Interleukin-1 (IL-1) is produced by activated monocytes/macrophages; highly increased amounts of IL-1 have been found in renal tissue in acute rejection of renal grafts. The endogenous inhibitor of IL-1, interleukin-1 receptor antagonist (IL-1ra), is produced in many cells in response to the same stimulus as IL-1. There is some evidence that the balance between IL-1 and IL-1ra is important in the regulation of inflammatory responses. In many inflammatory diseases in both humans and animals, a high concentration of endogenous IL-1ra or administration of exogenous IL-1ra has been shown to relate to shorter recovery time or to reduced mortality. METHODS: We measured the urinary excretion of IL-1ra and IL-1beta during the first 3-6 posttransplant weeks in 23 patients with acute rejection (69 24-hr urine samples) and in 17 patients with stable graft function (51 24-hr urine samples) and expressed the results as cytokine/creatinine ratios. RESULTS: Within the follow-up time, patients with rejection had higher urinary IL-1beta/creatinine (ng/mmol) ratios (median 5.0 vs. 2.7; P<0.005), lower IL-1ra/creatinine (ng/mmol) ratios (median 18.1 vs. 34.2; P<0.1), and consequently lower IL-1ra/IL-1beta ratios (median 3.6 vs. 20.3, P<0.005), compared with patients without rejection. In rejecting patients, IL-1ra/creatinine was constantly low and decreased even further during acute rejection, whereas IL-1beta/creatinine ratios increased from a median prerejection value of 3.5 (range not measurable to 9.0) to a median value of 8.1 (P<0.0005) (range 1.6 to 18.3) during rejection. CONCLUSION: These results suggest that patients who produce high amounts of IL-1ra in relation to IL-1beta are less prone to acute allograft rejection than patients with low IL-1ra/IL-1beta ratios.

Soluble intercellular adhesion molecule-1 (sICAM-1) after kidney transplantation: the origin and role of urinary sICAM-1?

BACKGROUND: Intercellular adhesion molecule-1 (ICAM-1) binds to leukocyte adhesion receptors LFA-1 and MAC-1, and mediates leukocyte adhesion to target structures. During acute rejection there is increased expression of ICAM-1 in vascular and tubulointestial cells, and consequently accumulation of inflammatory leukocytes. Soluble ICAM-1 (sICAM-1) is released from ICAM-1 expressing cells and excreted into the surrounding fluid. Increased serum sICAM-1 levels are found in patients with acute rejections of various allografts, and high urinary levels in steroid resistant acute kidney allograft rejection. METHODS: Urinary excretion of sICAM-1 was measured by EIA in 136 kidney allograft recipients during the first 1-6 post transplant weeks: 30 patients developed acute rejection, and 106 patients had stable graft function. The molecular weight, binding to hyaluronan, and the origin of urinary sICAM-1 were studied. RESULTS: We show that urinary sICAM-1 circulates as a monomer with a molecular weight between 50 and 100 kD. It binds to immobilized, but not to circulating hyaluronan. About one week after transplantation the mean sICAM-1/creatinine ratio (306 ng/mmol) in transplanted patients was higher than in the healthy controls (167 ng/mmol, P<0.01), and remained basically unchanged during the follow-up in patients with stable graft function, whereas it increased in patients developing rejection, being about 2.5-fold above the initial level a few days before rejection (P<0.01). Urinary sICAM-1 did not correlate with the urinary albumin, whereas in patients developing rejection it correlated with urinary IL-2R (r=0.5146, P<0.001), a marker of lymphocyte activation. In the urinary sediment of rejecting patients ICAM-1 was demonstrated in the tubular epithelial cells, and in the macrophages. CONCLUSIONS: Increased urinary excretion of sICAM-1 was demonstrated in kidney transplanted patients a few days before acute rejection. It seems to originate from activated macrophages and/or from the tubular epithelial cells. The fact that urinary sICAM-1 is not bound to hyaluronan or to leukocytes suggests that it is not able to compete with membrane-bound ICAM-1 for these bindings, but may do so for the binding of activated macrophages.

Serum transferrin receptor and erythropoiesis in children with newly diagnosed acute lymphoblastic leukemia.

Thirty-five children with acute lymphoblastic leukemia were monitored weekly during the first 12 weeks of chemotherapy. The transferrin receptor (TfR) concentration was 2.8 +/- 0.2 mg/l (mean +/- S.E.M.) at diagnosis, decreased up to 3 weeks, and then increased reaching a maximal level at 8 weeks. The mean values for reticulocyte counts followed a similar pattern. In contrast, serum erythropoietin and ferritin levels were generally high. Those patients whose erythropoiesis was more accelerated had higher serum TfR concentrations. We conclude that among these patients the TfR level reflected the rate of erythropoiesis and was independent of the level of erythropoietin.

Regulation of parathyroid hormone gene expression and peptide secretion in human parathyroid cells.

In cell cultures prepared from human parathyroid adenomas, parathyroid hormone (PTH) mRNA expression decreased slowly. During short-term incubations (less than 24 h), a low calcium concentration (0.5 mmol/l) and protein kinase C activator TPA (12-O-tetradecanoyl phorbol 13-acetate) (160 nmol/l) increased PTH secretion (60%; p < 0.05), while a high extracellular calcium concentration (2.5 mmol/l) reduced PTH secretion (60%; p < 0.05). The TPA could block the inhibitory effect of a high calcium level on PTH peptide secretion. All these agents had no effect on PTH mRNA accumulation in short-term experiments. In long-term cultures (more than 24 h), a low calcium level increased and a high calcium level reduced both PTH mRNA (85 and 34%; p < 0.05) and peptide secretion (140 and 80%; p < 0.05), respectively. The TPA reduced PTH mRNA accumulation down to 30% (p < 0.05) and PTH secretion down to 14% (p < 0.05) in a time- and dose-dependent fashion. The TPA also reversed the stimulatory effect of hypocalcemia on PTH mRNA accumulation and peptide secretion. Protein kinase C inhibitors staurosporine (100 nmol/l) and H-7 (1-(5-isoquinolinesulfonyl)-2-methylpiperazine dihydrochloride) (50 mumol/l) had similar effects to TPA on PTH gene expression and peptide secretion in long-term cultures. The results support the hypothesis that extracellular calcium regulates PTH mRNA accumulation and PTH secretion via protein kinase C.

Serum amyloid A levels in acute graft-versus-host disease in bone marrow transplant recipients.

We studied serum amyloid A levels of 31 bone marrow transplant recipients with and without acute graft-versus-host disease. Before transplantation the mean SAA concentration was 5.1 +/- 0.8 mg/l (mean +/- SEM). It remained low in patients with no signs of aGVHD but increased significantly during aGVHD to 54.0 +/- 8.2 mg/l (p less than 0.001 compared to pre-BMT value). Severe infections also induced high SAA levels.

Massive cutaneous hyalinosis. Identification of the hyalin material as monoclonal kappa light chains, adhesive 90 kD glycoprotein, and type I collagen.

The hyalin material in massive cutaneous hyalinosis, a disease characterized by extensive tumorous periodic acid-Schiff-(PAS) positive extracellular cutaneous deposits, has been elucidated by biochemical and immunologic methods. Three major components were found: kappa light chains, a mannose-rich glycoprotein, and type I collagen. Trace amounts of fibrinogen, fibronectin, laminin, IgG, pregnancy-specific glycoprotein, albumin, and keratan sulfate, but not keratin, were also present. The kappa light chains were monoclonal, cryoprecipiting, and more basic than the kappa chains from two myeloma patients. The glycoprotein, which could not be identified as any known glycoprotein, had an apparent molecular weight of 90,000 D. Amino acid analysis showed that glutamic acid, aspartic acid, leucine, and threonine were abundant, whereas hydroxyproline, hydroxylysine, and sulfhydryl amino acids were absent. The carbohydrate content of the protein was approximately 20%. The major monosaccharides were mannose and N-acetylglucosamine. Galactose, N-acetylneuraminic acid and fucose also were present. The third major component of the hyalin material was identified as type I collagen. A humoral immune response to the storage material was found: the patient's serum contained IgM and IgG class antibodies against the mannosylglycoprotein (90 kD glycoprotein) and against type I collagen.