Cytotoxic potential of stimulated human lymphocytes.

Viable and immunologically competent lymphocytes from unsensitized donors damage allogeneic tissue culture cells in the presence of phytohemagglutinin (PHA). This cytotoxicity is specific since syngeneic tissue culture cells are not at all or only slightly damaged under similar experimental conditions. In this investigation, the relation between the stimulation of human lymphocytes and their cytotoxicity was studied. Chang cells (human liver) served as target cells in all experiments. Cell damage was quantitated by measuring the release of isotope from target cells labeled with chromate-(51)Cr. The cytotoxicity of the lymphocytes was dependent on the concentration of PHA in the incubation medium. Cell damage was maximal at concentrations of 4-8 microl PHA/ml. Higher concentrations were inhibitory although aggregation was increased and no injury of the lymphocytes was noted. Stimulation of DNA and RNA synthesis in PHA-treated lymphocytes each followed dose response curves which were similar to that of cytotoxicity. In order to establish whether stimulation without mixed aggregation of lymphocytes and target cells would suffice for cytotoxicity, a series of nonagglutinating stimulants were investigated. Lymphocytes pretreated with a crude filtrate of Staphylococcus aureus for periods of 0.5-72 hr damaged Chang cells even in the absence of PHA. Lymphocytes from a tuberculin-positive donor were strongly cytotoxic after prestimulation with PPD while those from a negative donor were inactive. Moreover, strong cytotoxic effects were also obtained with lymphocytes which had been stimulated by preincubation with allogeneic lymphocytes in mixed culture. When two stimulants were applied at the same time, additive cytotoxic effects were seen. Addition of PHA to the lymphocyte/Chang cell mixtures potentiated the cytotoxicity of prestimulated lymphocytes. The cytotoxic potential of the lymphocytes was in all cases correlated to the degree of stimulation recorded as transformation into blast cells, and was independent both of the degree of aggregation and of the stimulating factor. These findings are compatible with the assumption that injury of the Chang cells reflected an immunologically nonspecific activity of lymphocytes enhanced by stimulation. The possible importance of this activity for a number of tissue-damaging immune reactions in vivo is pointed out.

Surface markers on human T and B lymphocytes. I. A large population of lymphocytes forming nonimmune rosettes with sheep red blood cells.

By using the two criteria (a) high density of immunoglobulin determinants on the cell surface and (b) presence of receptors for C'3 on the cell surface for defining bone marrow-derived lymphocytes, it is indirectly shown that all or at least a major population of human thymus-derived lymphocytes under certain conditions will form nonimmune rosettes with sheep red blood cells (SRBC). Almost all thymocytes tested from two different donors formed rosettes. The SRBC rosettes are not formed by virtue of immunoglobulin receptors and form only around living cells. Positive bivalent ions are required for rosette formation since EDTA will block rosette formation. Sodium iodoacetate will also block rosette formation demonstrating the dependence on an intact glycolytic pathway. Rosette formation is temperature dependent and will not appear at 37 degrees C. Trypsin treatment of lymphocytes will abolish their SRBC-binding ability which cannot be restored by treating them with fresh donor serum or fetal calf serum, but which will reappear after culturing the lymphocytes. It is suggested that these rosettes are formed by a rapidly released or metabolized receptor substance on the living cell surface which behaves as a trypsin-sensitive structure produced by the cells themselves.

Anxiety and depression symptoms in women with polycystic ovary syndrome compared with controls matched for body mass index.

BACKGROUND: Anxiety and depression are more prevalent in women with polycystic ovary syndrome (PCOS) than in those without this disorder. Possible confounding effects of overweight and obesity are suggested. The aim was to compare symptoms of anxiety and depression in women with PCOS and controls matched for age, body weight and body mass index (BMI). METHODS: Women with PCOS (n = 30) and controls (n = 30) were recruited from the community. Persons with ongoing psychotropic medication were excluded. All potential participants underwent gynecological examination to confirm case-control status. Participants completed the self-reported versions of the Brief Scale for Anxiety (BSA-S) and Montgomery Asberg Depression Rating Scale (MADRS-S). RESULTS: Women with PCOS had a higher BSA-S score compared with controls (median, range: 10.5, 1-24 versus 5.0, 0-28, P < 0.001). They scored higher on the following four individual symptoms: reduced sleep (2.0, 0-5 versus 0, 0-2, P < 0.001), worry (1.5, 0-4 versus 0, 0-6, P = 0.004), phobias (1, 0-4 versus 0, 0-3, P < 0.001), and pain (1, 0-3 versus 0, 0-2, P < 0.001). No statistical difference was demonstrated regarding MADRS-S scores (10.0, 0-27 versus 5.5, 0-24, P = 0.053). Only one of the nine MADRS-S symptoms, reduced sleep, which is also included in the BSA-S, differed between cases and controls. CONCLUSIONS: Several anxiety symptoms distinguished women with PCOS from a control group matched on BMI. A better understanding of the symptoms is needed to identify and alleviate anxiety symptoms in this vulnerable group.

Cytotoxic action of stimulated lymphocytes on allogenic and autologous erythrocytes.

Fowl erythrocytes are lysed when exposed to an excess of fowl blood lymphocytes in the presence of phytohemagglutinin. No significant cell damage is seen in the absence of phytohemagglutinin, or when the lymphocytes are replaced by malignant lymphoid cells, thymus cells, or nonlymphoid cells. The lymphocytes remain viable during the reaction. Differences in histocompatibility between lymphocytes and erythrocytes are not required. Autologous lymphocytes are cytotoxic to the same extent as allogenic lymphocytes over a wide range of experimental conditions.

Differences in blood T and NK cell populations between chronic lymphocytic leukemia of B cell type (B-CLL) and monoclonal B-lymphocytosis of undetermined significance (B-MLUS).

T and NK cell blood subpopulations were determined in 33 patients with B-CLL and in 14 patients with B-MLUS by two-color immunofluorescence. CLL patients had significantly higher total numbers of Leu-7+ and CD8+ cells and lower numbers of CD16+/Leu-7- cells as well as a higher Leu-7/CD16 ratio and a lower CD4/CD8 ratio than MLUS patients and control donors. Moreover, MLUS patients exhibited a significantly lower Leu-7/CD16 ratio as well as a higher frequency of CD16+/Leu-7- cells than healthy donors. These results suggest that B-CLL patients have higher numbers of circulating immature NK cells compared to B-MLUS, while B-MLUS patients have a larger proportion of NK cells with a high lytic capability as compared to both CLL and normal controls. The imbalance between CD4+ and CD8+ cells was prominent in CLL with a low CD4/CD8 ratio, but within the upper normal range in MLUS. Differences in immunoregulatory cell subpopulations between B-CLL and B-MLUS might therefore contribute to the different clinical behavior of these two disorders.

S-phase lymphocytes in chronic lymphocytic leukemia (CLL) in relation to immunoglobulin isotypes on the leukemic clone and to disease activity.

The fraction of blood S-phase (S+) lymphocytes from 41 patients with chronic lymphocytic leukemia of B cell type was determined by flow cytometry. The patients were grouped according to the smig isotype pattern of the leukemic cells. Patients with IgM as the predominant smig had higher numbers of S+ lymphocytes than patients with a leukemic clone co-expressing IgM and IgD (p less than 0.001). High relative as well as total numbers of S+ lymphocytes were associated with short therapy-free and overall survival. T cell proliferation was low although significantly higher in active than in indolent disease.

Cognition and autonomic function in schizophrenia: inferior cognitive test performance in electrodermal and niacin skin flush non-responders.

BACKGROUND: Patients with schizophrenia suffer from a broad range of cognitive disturbances. The impact in terms of functional outcome is significant. There are also several reports of disturbed autonomic regulation in the disease. The present study examined cognitive function as well as psychophysiological parameters in patients with schizophrenia and healthy controls. METHODS: Twenty-five patients and 14 controls were investigated with electrodermal activity (EDA), an oral niacin skin flush test and a comprehensive neurocognitive test program including the Wechsler battery (WAIS-R), Fingertapping Test, Trail Making Test, Verbal Fluency, Benton Visual Retention Test, Wisconsin Card Sorting Test and Rey Auditory Verbal Learning Test. RESULTS: The patients generally had inferior test results compared to controls. Further analysis revealed that the EDA non-responding patient group explained this variation with significant lower test results than controls. On executive tests, EDA non-responders also performed significantly worse than EDA responding patients. The small group of niacin non-responding patients exhibited an even lower overall test performance. Delayed niacin flush also correlated inversely with psychomotor function and IQ in the patients. CONCLUSION: The findings support the hypothesis of a neurodevelopment disturbance affecting both autonomic function and higher cortical function in schizophrenia.

Estrogen replacement therapy decreases hyperandrogenicity and improves glucose homeostasis and plasma lipids in postmenopausal women with noninsulin-dependent diabetes mellitus.

Hyperandrogenicity in women is closely associated with insulin resistance and a risk factor for cardiovascular disease and noninsulin-dependent diabetes mellitus (NIDDM). Therefore, 25 postmenopausal women with NIDDM and sex hormone-binding globulin values less than 60 nmol/L, as an indicator of a moderate hyperandrogenicity, were treated with 2 mg 17-beta-estradiol orally for 3 months in a double-blind, cross-over, placebo-controlled trial. During the last 16 days of active treatment, 1 mg norethisterone acetate was added for 10 days for endometrial protection. Blood glucose, glycosylated hemoglobin, insulin, c-peptide, lipoprotein profile, sex steroid hormones, GH, and insulin-like growth factor I (IGF-I) were measured, and insulin sensitivity was determined by the euglycemic hyperinsulinemic clamp method. All metabolic measurements were taken at baseline and after 68 days of active or placebo treatment. Estradiol treatment, compared with the placebo period, was followed by a marked increase of sex hormone-binding globulin and a decrease of free testosterone. Blood glucose, glycosylated hemoglobin, c-peptide, total cholesterol, low-density lipoprotein cholesterol, and IGF-I decreased significantly (P < 0.01-P < 0.001), whereas high-density lipoprotein cholesterol rose (P < 0.001). In conclusion, estrogen replacement therapy in postmenopausal women with NIDDM ameliorated hyperandrogenicity, and this was accompanied by marked improvements in glucose homeostasis and lipoprotein profile.

Hypertension in obesity and the leptin receptor gene locus.

Recent animal studies indicate that leptin is involved in the regulation of blood pressure through the leptin receptor. Therefore, 51-yr-old men (N = 284) were selected; and anthropometric, endocrine, metabolic, and hemodynamic variables were examined in relation to polymorphisms of the leptin receptor gene (LEPR), by restriction fragment length polymorphism technique. Three polymorphisms were examined: Lys109Arg in exon 4, Gln223Arg in exon 6, and Lys656Asn in exon 14. In comparison with Lys109 homozygotes, Arg109 homozygotes (9%) showed lower body mass index (BMI) and abdominal sagittal diameter, as well as lower systolic (10.0 mm Hg) and diastolic (7.8 mm Hg) blood pressure. Additionally, Arg223 homozygotes (26.8%) showed lower blood pressure (7.6/5.7 mm Hg) than Gln223 homozygotes. These lower blood pressure levels were independent of other variables. No differences were found with the Lys656Asn polymorphism. Measurements of body fat mass correlated with leptin concentration in Lys109 homozygotes and in Lys109 heterozygotes but not in Arg109 homozygotes. Blood pressure correlated with leptin only in men carrying the wild-type allele Lys109. With both elevated BMI and leptin, Lys109 homozygotes had higher blood pressure than the Arg109 homozygous men (12.4/6.9 mm Hg). Men with blood pressure > or = 140/90 mm Hg had, in comparison with normotensive men, increased BMI and leptin levels, and Lys109 homozygotes were significantly more prevalent. These results suggest that leptin is associated with blood pressure regulation in men through the leptin receptor. When BMI and leptin are elevated, increased blood pressure is found only with the most prevalent LEPR genotype at codons 109 and 223, whereas variants of this receptor seem to protect from hypertension. This might explain why not all obese men are hypertensive.

Polymorphisms of the androgen receptor gene and the estrogen receptor beta gene are associated with androgen levels in women.

To elucidate the possible role of genetic variation in androgen receptor (AR), estrogen receptor alpha (ER alpha), and ER beta on serum androgen levels in premenopausal women, the CAG repeat polymorphism of the AR gene, the TA repeat polymorphism of the ER alpha gene, and the CA repeat polymorphism of the ER beta gene were studied in a population-based cohort of 270 women. Total testosterone, free testosterone, dehydroepiandrosterone sulfate, androstenedione, 17-hydroxyprogesterone, 3 alpha-androstanediol glucuronide, 17 beta-estradiol, LH, FSH, and sex steroid hormone-binding globulin (SHBG) were measured in serum samples obtained in the follicular phase of the menstrual cycle. Women with relatively few CAG repeats in the AR gene, resulting in higher transcriptional activity of the receptor, displayed higher levels of serum androgens, but lower levels of LH, than women with longer CAG repeat sequences. The CA repeat of the ER beta gene also was associated with androgen and SHBG levels; women with relatively short repeat regions hence displayed higher hormone levels and lower SHBG levels than those with many CA repeats. In contrast, the TA repeat of the ER alpha gene was not associated with the levels of any of the hormones measured. Our results suggest that the serum levels of androgens in premenopausal women may be influenced by variants of the AR gene and the ER beta gene, respectively.

Guar gum improves insulin sensitivity, blood lipids, blood pressure, and fibrinolysis in healthy men.

A double-blind, placebo-controlled, cross-over study was carried out in 25 healthy, nonobese middle-aged men to test the effect of guar gum on glucose and lipid metabolism, blood pressure, and fibrinolysis. Ten grams guar or placebo granulate was given three times a day for 6 wk with a 2-wk run-in before and a wash-out period after. Decreases in fasting blood glucose (P < 0.001), cholesterol (P < 0.001), triglycerides (P < 0.05), plasminogen activator inhibitor-1 activity (P < 0.01), systolic blood pressure (P < 0.01), and diastolic blood pressure (P < 0.001) were seen during guar treatment when compared with placebo. Insulin sensitivity, measured with the euglycemic-clamp technique, increased (P < 0.01), adipose tissue-glucose uptake measured in vitro increased (P < 0.001), and 24-h urinary excretion of sodium and potassium increased (P < 0.001) during guar treatment. Fasting plasma insulin, renin, aldosterone, and fibrinogen concentrations as well as skeletal-muscle electrolytes, urinary catecholamines, and body weight remained unaltered. These findings support a role for guar in the treatment of the metabolic syndrome in which insulin resistance seems to play a pivotal role.

Increased muscle dynamic endurance associated with weight reduction on a very-low-calorie diet.

To assess muscle function after a period of negative energy balance, 32 obese women were placed on a 544-kcal/d, high-protein diet for 4 wk. Weight loss was associated with a decrease in the waist-to-hip-circumference ratio (WHR) and significantly higher emptying of abdominal than gluteal fat cells. The low-calorie regimen was associated with a significant increase in isokinetic muscle endurance, a decrease in glycogen concentration, and an increase in glycogen synthase (GS) activity and its fractional velocity (FV). The GS activity and its FV were negatively correlated with the WHR before treatment whereas their subsequent increase was correlated with the decrease in WHR. Dietary treatment produced a decrease in the isokinetic muscle strength, which was correlated with the reduction in lean body mass. The improvement in dynamic endurance observed after energy restriction parallels not only the increase in GS activity in muscle but also the decrease in glycogen stores and glucose oxidation, and most probably depends on the increased utilization of fatty acids.

Treatment of myasthenia gravis with anti-CD4 antibody: improvement correlates to decreased T-cell autoreactivity.

We treated a patient with severe myasthenia gravis with a chimeric (murine/human) anti-CD4 monoclonal antibody (cM-T412) for 7 days and followed the therapeutic effect by standardized muscle function tests, single-fiber electromyography, and immunologic examinations of disease-specific B- and T-cell functions. Clinical and electrophysiologic improvement began within 4 days, lasted for 3 months, and was maximal between days 16 and 58. The CD4+ lymphocytes decreased to a minimum of 80 cells per microliters of peripheral blood, recovered slowly during the first year of follow-up, and did not correlate with changes in disease severity. T-cell stimulation by human acetylcholine receptor was abolished by the treatment but became detectable at the time of worsening of symptoms. The concentration of acetylcholine receptor antibodies in serum was not decreased by the treatment. The results suggest that anti-CD4 antibody administration could be effective in the treatment of severe myasthenia gravis and indicate that acetylcholine receptor-specific T lymphocytes might contribute to the disturbed neuromuscular transmission in the disease.

Effect of a modified guar gum preparation on glucose and lipid levels in diabetics and healthy volunteers.

Six healthy volunteers and 17 diabetics (6 insulin-dependent and 11 diet- and tablet-treated) were treated with a special processed, palatable guar gum (10 g b.i.d. immediately before meals) for periods of one or three weeks or, in some cases, up to 13 weeks. A standardized test meal was given to study the effect of the fiber on postprandial glucose levels. Ten g guar was stirred in water and taken immediately before the test meal. The postprandial blood glucose levels were similar in the healthy volunteers but significantly lower in the diabetics following treatment with guar for one and three weeks, respectively. Furthermore, the fasting blood glucose levels were significantly lower in the diabetics after three, but not one, weeks of treatment. The lower postprandial glucose levels were coupled with attenuated and delayed insulin levels in accordance with an effect of guar gum on the rate of carbohydrate absorption. The cholesterol levels were on average reduced with 14% in the diabetics following three weeks' treatment with guar. The higher the initial cholesterol level, the greater the reduction in cholesterol; 26% reduction was achieved in four patients with initial levels above 7 mM. The alpha-lipoprotein cholesterol levels were not significantly changed, thus an increase in the alpha-lipoprotein cholesterol/total serum cholesterol ratio was obtained. Neither plasma triglycerides nor body weights altered during treatment. The reported side-effects were as expected and were usually mild and transient (e.g. increased flatulence). The data show that guar gum also reduces postprandial glucose levels on a long-term basis and may improve the diabetic control. Additionally, treatment with this fiber leads to a concentration-dependent decrease in cholesterol levels.

Comparison of antioxidant activity in lipoprotein fractions from insulin-dependent diabetics and healthy controls.

The insulin-dependent diabetic patient is at greatly increased risk of premature atherosclerosis. Oxidative damage to lipoproteins has been implicated as an important factor in the atherogenic process. Diabetic patients are exposed to excessive oxidative stress because of non-enzymatic glycation of proteins and a variety of defects in antioxidant systems. We have previously described an enhanced chemiluminescent method for measuring protective 'chain-breaking' antioxidant activity in plasma lipoprotein fractions. In this study we compare the lipid content and antioxidant activity of plasma lipoproteins in 22 young insulin-dependent diabetics without vascular complications and 20 age- and sex-matched controls. Mean levels of haemoglobin A 1c in the diabetic group were 8.8 +/- 0.2%. There were no significant differences in serum total cholesterol, apolipoprotein A, apolipoprotein B or lipoprotein(a) levels between the study groups. Serum total triglyceride levels (1.32 +/- 0.11 versus 1.01 +/- 0.08 mmol/l; P < 0.05) and LDL-associated triglyceride (0.28 +/- 0.04 versus 0.15 +/- 0.02 mmol/l; P < 0.05) were significantly elevated in the diabetic group. Total plasma antioxidant activity was significantly reduced in the diabetic group (272.0 +/- 15.4 versus 338.3 +/- 20.7 micromol/l; P < 0.05). Antioxidant activity measured in five lipoprotein fractions isolated by density gradient ultracentrifugation (VLDL1. VLDL2, LDL1, LDL2 and HDL) showed no significant differences between groups when corrected for protein, total lipid or cholesterol content. When corrected for triglyceride content significantly lower antioxidant values were found in the diabetic HDL fraction only. The results of this study imply that the susceptibility of the insulin-dependent diabetic to the development of premature atherosclerosis cannot be attributed to reduced antioxidant activity in circulating plasma lipoproteins.

C4 null alleles and myocardial infarction.

The classical risk factors, hypercholesterolemia, smoking, hypertension and diabetes, explain only a part of the epidemiological features of atherosclerotic coronary heart disease. Investigations in the past few years have shown involvement of immunological mechanisms in atherosclerosis. Circulating immune complexes accelerate atherosclerosis both in experimental animal models and in humans. The fourth component of complement (C4) plays an important role in the solubilisation and elimination of immune complexes. C4 consists of two allotypes, C4A and C4B. An earlier report showed an association between C4B null alleles (C4B*Q0) and myocardial infarction and to infarction related mortality. In the present investigation, C4A*Q0 and C4B*Q0 were studied in two population samples. The first (Group I) was a cross sectional study of 100 consecutive males with myocardial infarction before the age of 45 years and 164 population based healthy controls, age and sex matched. The second (Group II) was a nested case control study in which a cohort of 50 year-old males were followed for 20 years for development of myocardial infarction between 50-60 and 60-70 years, and the results compared with those who did not develop MI. We observed no association of homozygous and/or heterozygous C4A*Q0 or C4B*Q0 with myocardial infarction occurring in the age groups < 45, 50-60 and 60-70 years or with the infarction related mortality (P > 0.05). The prevalence/frequency of C4A*Q0 and C4B*Q0 was not related to the age at which MI occurred. The prevalence of C4A*Q0 was not affected by age. We thus conclude that partial deficiency of C4 does not appear to be a major risk factor for myocardial infarction.

Tocopherol and local X-ray irradiation of two transplantable rat tumours.

The influence of tocopherol in an intramuscular dose of 5 mg/100 g body wt. on the effect of local X-ray irradiation of 2 intramuscularly transplanted tumours in the rat was studied. A significantly enhanced effect of irradiation by tocopherol was found, in contrast to the tumour radioprotecting effect with large doses of tocopherol earlier described in literature.

Higher T-cell imbalance and growth factor receptor expression in B-cell chronic lymphocytic leukemia (B-CLL) as compared to monoclonal B-cell lymphocytosis of undetermined significance (B-MLUS).

The surface marker phenotype of lymphocytes derived from 12 patients with B-CLL was compared to that of lymphocytes from 10 patients with an other monoclonal but clinical benign form of B-cell proliferative disorder termed monoclonal B-cell lymphocytosis of undetermined significance (B-MLUS). A panel of well characterized monoclonal antibodies was used for the surface marker determinations. The mean total number of B cells (CD20) was 8.5 x 10(9)/1 in B-MLUS as compared to 44 x 10(9)/1 in B-CLL (p less than 0.001). B-CLL had a greater imbalance in T-cell subpopulations than B-MLUS and healthy controls. Total numbers of CD3+, CD8+ cells as well as cells expressing the NK-related antigens (CD16, Leu-7) and IL-2 receptor (CD25) bearing lymphocytes were statistically significant higher in B-CLL than in B-MLUS. Analyses of B-cell enriched populations showed that B-CLL represented B cells of an early maturation stage, whereas B cells from B-MLUS were more mature as judged by the loss of the CD21 surface marker. A larger fraction of B cells in B-CLL compared to B-MLUS exhibited a higher activation stage as revealed by the expression of the CD21, CD25 and CD35 structures as well as the FMC7 antigen.