Increased soluble interleukin-2 receptor levels in the sera of type 1 diabetic patients

Recently, the presence of a soluble form of IL-2 receptor (IL-2RS) in human sera and in supernatants of PHA-stimulated lymphocytes has been demonstrated. It has been suggested that autoimmune diseases could be characterized by a defect in production of IL-2RS, unlike immunoproliferative disorders which are characterized by overproduction. Our aim was to investigate serum IL-2RS levels in 35 newly diagnosed Type 1 diabetic patients, in 25 age-matched healthy blood donors and in five patients with Hodgkin's disease. We found that newly diagnosed diabetic patients have higher IL-2RS levels (424.8 +/- 203 U/ml) than normal controls (252.4 +/- 38.4 U/ml) (p less than 0.005). In 22 out of 35 patients (62.8%) the IL-2RS values were above the higher 95% tolerance limit of controls. Furthermore, the persistence of high IL-2RS levels was observed in 18/35 diabetic patients six months after diagnosis (470 +/- 195.6 U/ml). The increased levels were not correlated with glycaemic and HbA1c levels and patients' age. Our findings suggest a potentially significant role for the released IL-2R in the regulation of IL-2 dependent lymphocyte functions in Type 1 diabetes. The study of IL-2RS in Type 1 diabetes may provide a new tool for the knowledge of cytokine involvement in the disease.

Prevalence of residual B-cell function related to age at onset and genetic profile in newly diagnosed type I diabetics

Patients with type I (insulin-dependent) diabetes mellitus maintain B-cell function for a varying period of time after onset. This is commonly held to account for post-initial remission. To estimate residual B-cell function we measured plasma and 24-h urinary C-peptide in 68 type I diabetic patients (age range 4-35 years, within 10-180 days of the onset of symptoms, typed for HLA-A, -B, -C and DR loci. A positive correlation (r = 0.26; p less than 0.05) was found between urinary C-peptide levels and the age of the patient. The analysis of variance of urinary C-peptide values on the basis of the presence or absence of DR3 and DR4 antigens revealed that the DR3-positive patients had reduced excretion (15.2 +/- 9.2 SD micrograms/24h) with respect to the others (22.7 +/- 15.5 SD micrograms/24h) (F = 6.35; p less than 0.05). No interaction effect was found in DR3/4 positive patients. Hence, late onset patients appear to have higher residual C-peptide secretion. In the light of these findings, the assessment of B-cell function and genetic profile may be useful in predicting which patients are likely to have remission periods and identifying the metabolic consequences of even minimal endogenous insulin secretion.

Visual evoked potentials in insulin-dependent diabetics

The latency of pattern-reversal VEPs was studied in type I insulin-dependent diabetics without retinal and extraocular involvement. One hundred eyes of 50 diabetics (mean age 19.8 +/- 7.2 years) formed the study group; the duration of the disease ranged between 1 month and 15 years. The latencies of VEPs were progressively delayed in relation to the duration of the disease, becoming more and more evident and stabilizing after about 6 years from the onset of diabetes. The VEP alterations probably indicate alteration of membrane balance or demyelinization.

Immunoregulatory T-lymphocyte subset deficiency in newly diagnosed type 1 (insulin-dependent) diabetes mellitus

Humoral and cell-mediated disorders in Type 1 (insulin-dependent) diabetes suggest that an imbalance of immunoregulatory T-cell subsets exists. In 23 newly diagnosed (onset less than 3 months) and 21 long-standing Type 1 diabetic patients, T lymphocyte subsets were analyzed using monoclonal antibodies (OKT3, OKT4, OKT8, OKM1). The newly diagnosed patients showed a reduction with a significant difference from healthy controls in total T cells (OKT3+: 58.1 +/- 8.5% versus 70.7 +/- 8.0%), helper/inducer cells (OKT4+: 33.8 +/- 7.0% versus 47.1 +/- 8.3%), suppressor/cytotoxic cells (OKT8+: 18.5 +/- 7.3% versus 32 +/- 6.8%) and monocytes (OKM1+: 11.5 +/- 3.8% versus 19.9 +/- 5.2%) (p less than 0.001). The long-standing diabetic patients also revealed a low number of immunoregulatory T cells compared with control subjects, although to a lesser extent (p less than 0.01-0.05). The helper/suppressor ratio (OKT4+/OKT8+) was higher in newly diagnosed patients than in control subjects (2.2 +/- 1.3 versus 1.5 +/- 0.3; p less than 0.02). When compared with 95% tolerance limits in the control subjects, the reduction of OKT8+ cells in the newly diagnosed diabetic patients appeared more marked: the mean (18.5%) coincided with the lower limit of normal subjects (18.3%). Ten of the newly diagnosed Type 1 diabetic patients had a value below the normal lower limit. Out data point to the occurrence of different immunoregulatory abnormalities in newly diagnosed Type 1 diabetic patients, especially in OKT8+ and OKT4+ cells. The imbalance in T lymphocyte subsets is further proof of the role of cellular autoimmunity in the pathogenesis of the early phases of Type 1 diabetes.

Circulating immune complexes containing IgG, IgA and IgM in patients with myocardial infarction: detection with C1qSP and anti C3SP

Immunological reactions have been recognized in cardiac disease and immune complexes (ICs) have been suggested to be of pathogenetic significance in the occurrence of post-myocardial infarction syndromes. ICs of IgA, IgG, IgM class have been detected in myocardial infarction utilizing a C1qSP and an anti C3 assay. A poor concordance was found between the two methods. Early pericarditis was found to be associated with the presence of ICs, suggesting that ICs may play a role in developing pericarditis or that they may be considered a marker of pericarditis by an immunological mechanism.

Leukocyte migration test (LMT) in patients with thyroid disease: the response to human thyroid subcellular fractions

The response of circulating leukocytes to thyroid subcellular fractions was investigated in 19 patients with Graves' disease, 15 patients with Hashimoto's thyroiditis, 7 patients with toxic adenoma, 19 patients with nontoxic goiter and in 10 healthy students as control subjects. For this purpose, the leukocyte migration test of Soborg and Bendixen was performed against human crude thyroid extract (CTE), cell plasma membranes, nuclei, ribosomes, mitochondria and microsomes. Our results show positive LMT against: 1) CTE in patients with Graves' disease (61 +/- 13, p less than 0.001) and Hashimoto's thyroiditis (65 +/- 11, p less than 0.001) compared to controls (90 +/- 11); 2) cell plasma membranes in patients with Graves' disease (41 +/- 14, p less than 0.001) and Hashimoto's thyroiditis (64 +/- 21, p less than 0.05) compared to controls (88 +/- 19); 3) nuclei in patients with Graves' disease (53 +/- 25, p less than 0.001) and Hashimoto's thyroiditis (53 +/- 23, p less than 0.001) compared to controls (83 +/- 11). Our findings of circulating leukocytes sensitized to cell plasma membranes and nuclear fraction in patients with Graves' disease and Hashimoto's thyroiditis provide the additional information that these patients have a specific defect in immune-surveillance.

[Blood level of thyroid hormones in surgical thyroid diseases. Pre-,intra- and post-operative T3 and T4 levels]

A pre-, intra- and post-operative determination of thyroid hormone in values in the peripheral and thyroid vein reflux blood of patients with thyroid disorders requiring surgery showed that the so-called intraoperative squeezing of the gland either does not place or is of little importance when delicate surgical movements are commenced. A low incidence of intraoperative arrhythmia was also noted. Prevention of the latter is not indicated, since it is often dependent on surgical movements and/or unorthodox anaesthesiological management.