Evidence for immune activation against oxidized lipoproteins in inactive phases of juvenile chronic arthritis.

OBJECTIVE: Oxidative stress contributes to joint inflammation and damage in rheumatoid arthritis. In a mobile inflamed joint, exercise induced multiple cycles of hypoxia-reperfusion injury may lead to the creation of a redox environment in which oxido-reductase systems, by NADPH mechanisms, produce highly reactive chemical species (i.e., oxygen free radicals). We investigated 2 endproducts of lipid peroxidation, malonildialdehyde (MDA) and diene conjugates (DC), and the formation of antibodies against oxidized low density lipoproteins (Ab oxLDL) in juvenile chronic arthritis (JCA), and assessed the role of oxidative phenomena in different phases and subsets of this disease. METHODS: To assess the role of oxidative stress in JCA, we measured the endproducts of lipid peroxidation, MDA and DC, by the increase of absorbance at 586 nm and 234 nm, respectively, and the levels of Ab oxLDL by ELISA in the sera of 58 patients with JCA and 21 healthy controls. Due to crossreactivity between Ab oxLDL and anticardiolipin antibodies (aCL), the sera were also tested by a standard ELISA for IgG-aCL. The patients were divided into 3 subsets: 29 with pauciarticular (pauci), 15 with polyarticular (poly), and 14 with systemic (sys) onset disease, and then were subdivided, according to different variables appropriate to each subset, reflecting active and inactive disease, into 30 active (14 pauci, 8 poly, 8 sys) and 28 inactive (15 pauci, 7 poly, 6 sys). RESULTS: Levels of Ab oxLDL were significantly increased in the whole group of patients (566.6 +/- 263.0 vs 206.6 +/- 136.3 mU/ml; p < 0.001) and in each of the type of onset (pauci 660.8 +/- 272.1, p < 0.001; poly 341.3 +/- 134.7, p < 0.01; sys 497.8 +/- 114.8, p < 0.001) compared to controls. Ab oxLDL were higher in the inactive than in the active group (743.5 +/- 231.9 and 404.4 +/- 169.9; p < 0.001). MDA and DC levels were not increased significantly in patients' sera. No patient was positive for IgG-aCL. CONCLUSION: These findings suggest that MDA and DC cannot be considered major markers of oxidative stress in JCA and that the Ab oxLDL may represent a delayed sign of oxidative stress previously induced by the inflammatory process in patients with JCA.

Detection of human apolipoprotein E genotypes by DNA electrochemical biosensor coupled with PCR.

BACKGROUND: Apolipoprotein E (apoE) is an important constituent of several plasma lipoproteins, mainly VLDL, HDL, and chylomicrons. It is involved in the redistribution of lipids in the liver and is implicated in growth and repair of injured neurons in the nervous system. apoE has also been associated with the risk of developing cardiovascular diseases and in familial type III hyperlipoproteinemia. METHODS: We developed a new procedure for detecting genetic polymorphisms of apoE in human blood samples. The procedure is based on coupling of DNA electrochemical sensors with PCR-amplified DNA extracted from human blood. The DNA electrochemical sensor incorporated single-stranded oligonucleotides immobilized on graphite screen-printed electrodes (SPEs) by adsorption at controlled potential. The hybridization reaction on the electrode surface was monitored by chronopotentiometric stripping analysis (PSA), using daunomycin as indicator. RESULTS: With use of two different probes, it was possible to investigate both DNA positions in which the apoE polymorphism takes place and thus to distinguish different genotypes. Real samples containing only complementary sequences gave a good increase in the area of the daunomycin peak ( approximately 600 ms) compared with the peak observed with the buffer. Samples containing 50% complementary sequences gave a much lower increase, and samples containing only mismatch sequences gave a decrease in the daunomycin area. The procedure was validated by comparison with a method based on polyacrylamide gel electrophoresis. CONCLUSION: The coupling of DNA electrochemical sensors with PCR allowed quick discrimination between the different genotypes of apoE.

Coupling of a DNA piezoelectric biosensor and polymerase chain reaction to detect apolipoprotein E polymorphisms.

In this paper we report the coupling of the Polymerase Chain Reaction (PCR) with a piezoelectric biosensor to detect a point mutation in a human gene. Biotinylated 23-mer probes were immobilised on the streptavidin coated gold surface of a quartz crystal; streptavidin was covalently bound to the thiol/dextran modified gold surface. The hybridisation of the immobilised probes with a short sequence (23 mer) complementary, non-complementary and mismatched DNA was investigated: the device was able to distinguish the different synthetic oligonucleotides. Many cycles of measurements can be performed on the same crystal surface regenerating the single strand of DNA with 1 mM of HCl. The same hybridisation reaction was then performed using real samples of human DNA extracted from blood and amplified by PCR, following a standard procedure for genetic detection of the polymorphism of the apolipoprotein E (apoE) gene. The procedure was able to distinguish the sequences present in the different samples, which differ only in one base: in this way it was possible distinguish between different groups of genotypes with apoE typing. Experiments with 'blank' samples confirmed the absence of adsorption or non-specific effects on the quartz crystal treated with the reported procedure.

Oxidative stress in Systemic Sclerosis.

In 63 patients affected by Systemic Sclerosis (SSc) (limited subset: 40; diffuse subset: 23; early: 30; advanced: 33) the peroxidation product diene-conjugates (DC) and antibodies against oxidised low density lipoproteins (Ab oxLDL) were tested in serum by a spectrophotometer (absorbance 234 mn) and by a standard ELISA respectively. The data were compared with those obtained by 21 healthy subjects. DC was significantly higher in patients (73.3 +/- 37.2 microM/l; p < 0.0001) than in controls (48.4 +/- 16.7) as well as in the limited (80 +/- 48.8; p < 0.05) than in the diffuse subset (64.5 +/- 36.4); and in early (84.1 +/- 31.4; p < 0.05) than in advanced stage of the disease (67.9 +/- 42.5). The levels of Ab oxLDL were significantly higher in SSc patients (309.5 +/- 367.2 mU/ml; p < 0.0001) in all its subsets (limited: 351.9 +/- 351.1, p < 0.0001; diffuse: 207.7 +/- 316.1, p < 0.05; early: 428.9 +/- 417.1, p < 0.001; advanced: 302.7 +/- 89.9, p < 0.0001) than in controls (89.3 +/- 29.1). These antibodies levels were higher in limited subset than in diffuse (p < 0.05) and in early SSc than in advanced SSc (p < 0.05). The highest values of parameters of oxidative stress are found in the early stages, when the episodes of reperfusion after ischemic episodes (Raynaud's phenomenon) are very frequent. Moreover, the damage is higher in the early stages of SSc, with intact microvessels, than in late stages, when microvessels are very reduced in number, destroyed by the worsening of the disease. These data show that the respiratory burst deduced by the lipoperoxidation is higher in SSc than in controls, and may be an important pathogenetic factors involved in tissue changes in SSc.

Lipoprotein (a) induces angiogenesis on the chick embryo chorioallantoic membrane.

BACKGROUND: Both lipoprotein (a) [Lp(a)] and angiogenesis have been shown to be associated with initiation and progression of atherosclerotic plaque. Lp(a) and two neutralizing anti-Lp(a) antibodies were investigated for their capacity to affect the vasoproliferative processes of the chick embryo chorioallantoic membrane (CAM), a useful model for such an investigation. METHODS: Gelatin sponges loaded with Lp(a) alone or together with anti-Lp(a) antibodies, or with vehicle alone, phosphate-buffered saline (PBS), were implanted in vivo onto the CAM at incubation day 8. Four days later, sponges and the adjacent CAM tissues were assessed for the extent of angiogenesis in terms of microvessel counts. RESULTS: Lp(a)-loaded sponges gave significantly higher counts than those loaded with the LP(a)-anti-Lp(a) antibodies complex, which overlapped those treated with PBS. The angiogenic response was similar to that obtained with basic fibroblast growth factor, a well known angiogenic molecule. CONCLUSION: These data suggest that Lp(a) is capable of inducing angiogenesis in vivo, which might account for its ability to enhance and support atherosclerosis.

[Detection of the human papillomavirus in hyperplastic and cancerous prostatic tissue with PCR]. / Ricerca di papillomavirus umani nel tessuto prostatico iperplastico e canceroso mediante PCR.

Human papillomavirus (HPV) infections are frequently associated with benign, pre-malignant and malignant lesions of the female genital region and male anogenital tract. Recently several studies have been performed to evaluate the presence of HPV in the adenomatous and carcinomatous prostatic tissue for the epidemiological implications due to the sexual transmission, and for the possible etiologic role in the development of prostatic carcinoma, first cause of death from neoplasia in men over 60 years in the developed countries. The role of HPV is still controversial since some authors evidenced the virus in prostatic tissue others did not detect its presence. We investigate the presence of HPV in 60 prostatic benign hyperplasias and in 5 prostatic carcinomas in surgically resected prostates by PCR technique using consensus and type specific primers. The analyzed specimens were negative for HPV DNA, although appropriate amplimers were present for beta-globin and positive controls. We therefore conclude that HPV infections are not commonly found in the human prostate.

Substance P in the serum of patients with rheumatoid arthritis.

Serum substance P was assayed in rheumatoid arthritis patients and healthy controls to evaluate whether neurogenic inflammation with substance P release is significant in rheumatoid arthritis. A very sensitive competitive immunoenzymetric assay was used. Mean serum substance P level was significantly higher in rheumatoid arthritis patients than in controls and was not correlated with disease duration, morning stiffness duration, Thompson's articular index, Larsen's radiographic score, or the following laboratory indices of inflammation: erythrocyte sedimentation rate, C-reactive protein, and alpha 1-acid glycoprotein. Neurogenic inflammation with substance P release may contribute significantly to the pathogenesis of rheumatoid arthritis. The absence of correlations between serum substance P and clinical or laboratory indices of inflammation may reflect complex interactions between neurogenic inflammation and other pathogenic mechanisms, which may influence clinical features and laboratory tests in rheumatoid arthritis patients.

Acanthocytosis, retinitis pigmentosa, pallidal degeneration. Report of two cases without serum lipid abnormalities.

We describe two unrelated patients with Hallervorden-Spatz, disease characterized by prominent facio-bucco-lingual dyskinesia. Acanthocytosis and retinitis pigmentosa were additional findings. Brain MRI showed the typical 'tiger's eye' image of the globus pallidus. This phenotype closely resembled the so-called HARP syndrome (hypoprebetalipoproteinemia, acanthocytosis, retinitis pigmentosa and pallidal degeneration), but extensive serum lipid study failed to demonstrate any lipoprotein abnormality. Our results raise the question whether HARP syndrome is an autonomous entity or a particular phenotype of Hallervorden-Spatz disease.

Intracellular diacylglycerol: a mitogenic second messenger proposable as marker of transformation in squamous cell carcinoma of the lung.

In this study, we examined 50 patients with documented lung cancer projecting in the bronchial lumen unilaterally. Bronchial lavage from the affected and unaffected sides provided neoplastic and normal cells in which we studied an intracellular mitogenic second messenger, diacylglycerol, associated with transformation. The levels of diacylglycerol in cells from the affected side were compared with that from the healthy side, thus providing an internal control for each patient. Our data show that the levels of diacylglycerol in lavage fluid relative to affected bronchus are elevated in 56% of all the patients examined. This elevation reaches 77% in patients with squamous cell carcinoma, a value of sensitivity higher than 'traditional' markers for cancer of the lung. Thus, these findings may have significant implications for the use of diacylglycerol measurement as a novel biomarker for early detection of lung cancer, and for monitoring recurrences after treatment.

Adjuvant effect of low-dose interleukin-2 on antibody response to influenza virus vaccination in healthy elderly subjects.

It is well known that immune efficiency is frequently deteriorated in elderly people. The age-diminished antibody response to T-cell dependent antigens, such as influenza virus antigens, may explain the low protection offered by influenza vaccination in the elderly population. To investigate the possibility of increasing the antibody response to influenza virus vaccinations, we have conducted a nursing home-based study on the efficacy of IL-2. Seventy-five institutionalized elderly subjects (82 +/- 8 years) were enrolled in the study in the course of winter season 1991-1992. Thirty-nine subjects were treated with three subcutaneous daily injections of interleukin-2 (IL-2, 1 x 10(6) I.U./day) before vaccination and their antibody response was compared to that of 36 aged people receiving the vaccine only. An increased antibody response against influenza virus was present in vaccine plus IL-2 treated subjects (P < 0.001) but not in subjects treated with vaccine only. The number of protected subjects 45 days after vaccination was increased only in the IL-2-treated group (P = 0.045). The low-dose of IL-2 administered and the short-term treatment allowed a good tolerance to the IL-2 injection. In conclusion, the low-dose IL-2 treatment represents an effective means of inducing antibody response to influenza virus antigens in elderly subjects without appreciable toxicity.

Analysis for transaminases in serum with an amperometric glutamate electrode.

We determined transaminases in human blood serum with an amperometric glutamate biosensor. The probe was a hydrogen peroxide sensor assembled with appropriate selective membranes to enhance the probe specificity and lifetime. Calibration curves of glutamate were linear in the range 1-1000 mumol/L, with a response time of < 1 min. This probe was subsequently applied to the measurement of activities of aspartate and alanine aminotransferases in human sera. Analytical recovery studies demonstrated the suitability of the glutamate sensor by measuring 91-99% of added glutamate, 92-106% of added aspartate aminotransferase, and 101-105% of added alanine aminotransferase. Transaminase activity measured in 80 sera correlated well with results obtained with a spectrophotometric procedure.

[Lymphocyte subpopulations in multiple sclerosis (MS). A contribution]. / Le sottopopolazioni linfocitarie nella sclerosi multipla (SM). Un contributo.

The characterization of peripheral blood T-cell subpopulations in 29 multiple sclerosis (MS) patients is studied. A direct immunofluorescence assay was performed using monoclonal antibodies (OK series) directed to lymphocytes surface antigens. In transverse study, the patients suffering from progressive MS showed T4+ lymphocytes and T4+/T8+ ratio significantly high (p less than 0.05) compared to controls; furthermore T8+ lymphocyte values were low. T3+ lymphocytes were low (p less than 0.05) during the relapse in the MS remitting relapsing patients. A six month follow-up of the patients showed, during relapse, a reduction and, immediately after, a recovery of T3+ and T4+ lymphocyte values; T8+ lymphocytes didn't show remarkable fluctuations.

Long-term study on T lymphocyte subsets in newly diagnosed type 1 diabetes mellitus.

T lymphocyte subsets in peripheral blood from 16 newly diagnosed type 1 diabetic children were studied prospectively at four time intervals: as soon as possible after diagnosis and 1, 4 and 12 months later. T lymphocyte subsets were analysed using monoclonal antibodies and counted by cytofluorimetry. The percentage of T lymphocytes (OKT3+ cells) did not change at the four study times. The percentage of helper/inducer T cells (OKT4+ cells) was high at the diagnosis (43.1 +/- 2.1%), but decreased after 1 and 4 months with no difference in the control values. The percentage of suppressor/cytotoxic T lymphocytes (OKT8+ cells) was low at the diagnosis, but increased after 1 and 4 months. The OKT4/OKT8 ratio was 2.31 +/- 0.22 at the diagnosis study, decreasing to 1.83 after 1 month, compared with 16 sex- and age-matched control children. The high percentage of helper/inducer T lymphocytes and low number of suppressor/cytotoxic T cells at onset of diabetes favour immune reactions that lead to beta-cell damage.

Antibodies anti-HTLV III and lymphocyte subsets of high risk subjects.

208 assay for the research into anti-HTLV III antibodies and lymphocytes subsets were carried out on the same number of patients at risk. 11 homosexual man, 143 intravenous drug users (i.d.u.) and 3 children of drug addicts from hospitals in the Marche and Abruzzo and 51 haemophiliacs from hospital in Florence were examined. 3 determination of anti-HTLV III antibodies were taken from each subject using 3 different commercial Kits. The results concur with and confirm similar epidemiological studies that have been done. The haemophiliac group had the highest positive percentage (39.2%), then came i.d.u. (11.9%) and the homosexuals (10.0%). Furthermore, of the 38 positive totals, there were 22 with only one kit, 18 with two, and 15 with all three. The evaluation of the lymphocyte subsets did not strictly correlate with the presence of the antiretrovirus antibodies.