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Myasthenia gravis (MG) is an autoimmune disease characterized by muscle weakness and pathogenetic autoantibodies directed against the nicotinic acetylcholine receptor (seropositive myasthenia gravis; SPMG). Nearly 15% to 20% of MG patients do not have these antibodies (seronegative myasthenia gravis; SNMG), but several evidence indicate that these patients have circulating pathogenic autoantibodies directed against other muscle antigens. Using the TE671 rhabdomyosarcoma cell line as an antigen source, we analyzed sera from 63 SNMG and 26 SPMG patients and 26 healthy blood donors by FACS analysis. We found that 40 of 63 SNMG patients and only 1 of 26 SPMG patients had IgG binding to the TE671 cell line. None of the sera bound to the unrelated MRC5 cell line. To identify the antigen, we analyzed sera immunoreactivity in more detail by immunoprecipitation of biotinylated membrane proteins from TE671 cells. When the immunoprecipitated proteins were separated by SDS-PAGE electrophoresis and then transferred to nitrocellulose membranes, we found that SNMG IgG identify a band corresponding to a protein with a molecular weight of 110 kDa (P110), which is not recognized by seropositive MG sera. This anti-P110 immunoreactivity is significantly associated with a distinct clinical picture characterized by a prominent involvement of ocular and bulbar muscles, with frequent respiratory problems (p < 0.005), and is recognized by a specific antimuscle specific kinase (MuSK) antiserum. In a recent article, the presence of anti-MuSK antibodies was described in SNMG. Our results confirm the presence of these antibodies in SNMG and suggest that anti-P110/MuSK autoantibodies identify a subtype of SNMG in which the different pathogenesis induces the distinct clinical picture.

Prolactin (PRL) and glucocorticoids are hormones involved in the regulation of the immune system. Rheumatoid arthritis (RA) is an inflammatory condition that presents a diurnal rhythm of disease activity. PRL/cortisol ratio, and IL-1beta and TNF-alpha levels were determined in patients with RA and in control subjects at 0600, 1000, 1400, 1800, 2200, and 0200 hours. In patients with RA we observed higher PRL/cortisol ratio at 0200 hours, whereas IL-1beta and TNF-alpha reached their highest serum levels at 0200 and 0600 hours. In patients with RA we observed an imbalance in favor of proinflammatory hormones as opposed to levels of antiinflammatory hormones during nocturnal hours together with increased levels of IL-1beta and TNF-alpha of the diurnal rhythm of disease activity.

Objective: To compare secretory immunity in cecal and ileal orthotopic neobladders, and to detect its permanence over time., Patients and Methods: IgA was studied in the urine of 33 patients with ileocecourethrostomy (ICUS) and 13 patients with ileal reservoir (IR). The mean follow-up was 55 months. Results were compared in terms of the type of operation, a healthy control group, and the time since surgery., Results: Urinary IgA levels were significantly higher in ICUS and IR patients than in normal controls. No significant differences in IgA concentrations were detected in patients with different reservoirs and with regard to time., Conclusion: Both the reservoirs maintain the function of producing IgA. In particular no differences were detected over time and urine could be a permanent antigenic stimulus. IgA could be considered an adjunctive factor for upper urinary tract protection. For this reason we prefer to use a simple, indirect antireflux mechanism, thus avoiding direct manipulation of the uretero-intestinal anastomosis., (Copyright 2001 S. Karger AG, Basel)

Transforming growth factor-beta (TGF-beta) is involved in several autoimmune neurological diseases. It is still unclear whether its local action can be pro-inflammatory or anti-inflammatory in the muscle tissue, because of the few reports on this subject. We have previously shown that human myoblasts secrete interleukin-6 (IL-6) when stimulated with inflammatory cytokine such as interleukin-1beta (IL-1beta) or tumor necrosis factor alpha. In the present report, we show that TGF-beta1 can induce IL-6 production; moreover, costimulation or short term pre-incubation with TGF-beta1 increases IL-1beta effect, while a longer incubation inhibits its action.

Background and Objective: The feasibility of gene marking or gene therapy protocols making use of purified CD34+ cells greatly depends on the efficiency of their stable transduction. The great potential of umbilical cord blood as a source of CD34+ cells combined with the availability of advanced cell purification procedures prompted us to evaluate whether incubation with growth factors might influence the type of cells effectively transduced by retroviral vectors., Design and Methods: Isolated, at least 95% pure, CD34+ cells were infected with the LXSN murine retrovirus carrying the neomycin-resistance gene. Different schedules of CD34+ cell infection were performed with or without incubation for different times in the presence of Interleukin-3 (IL-3), Interleukin-6 (IL-6) and stem cell factor (SCF). Efficiency of transduction was evaluated by clonogenic assays, semiquantitative PCR and RT-PCR analyses performed either immediately or after 7 day expansion of CD34+ cells in liquid culture in the presence of erythropoietin (EPO), IL-3 and granulocyte-macrophage colony-stimulating factor (GM-CSF)., Results: The results obtained indicated that the amount of transduced cells increased with the lenght of incubation with growth factors, either before or during infections. However, different types of cells were transduced depending on the duration of stimulation and infection. Thus, following one week culture of CD34+ cells in the presence of EPO, IL-3 and GM-CSF the clonogenic potential was affected dyshomogeneously. Precisely, with a single 3-hour infection performed after 12 hours of stimulation with growth factors, the clonogenic potential of the transduced cells greatly increased after one week in culture. In contrast, with a 48 hour infection, the transduced cells completely lost their clonogenic potential after one week in culture., Interpretation and Conclusions: These results demonstrate that a reasonably high transduction efficiency of purified CD34+ cells can be achieved with short schedules of incubation/infection in the absence of stroma or extracellular matrix.

The occurrence and clinical value of anticardiolipin antibodies (aCL) were studied in 33 patients with giant cell arteritis (GCA) and in seven patients with polymyalgia rheumatica (PMR), at onset and during follow-up. aCL were present in 19/40 (47.5%) GCA/PMR cases, most of them of the IgG isotype, whereas all controls (21 subjects) were aCL negative. The presence of aCL was not associated with inflammatory parameters or clinical signs of arteritis; however, they disappeared in a significant percentage (56%) of patients during steroid therapy. No correlation was found between ischaemic events and aCL, suggesting that they are not important for the development of vascular complications in GCA/PMR patients. Moreover, a retrospective evaluation of our data showed a correlation between aCL positivity and anaemia, whose significance remains to be elucidated.

In order to evaluate the autoantibody pattern of subjects affected by rheumatoid arthritis (RA) with clinical features of keratoconjunctivitis, we studied 32 out- and in-patients (26 women, 6 men, average age 52 years, average disease duration 5.5 years) at the Division of Rheumatology, Catholic University of Rome. We found keratoconjunctivitis sicca and xerostomia in 22 (68.75%) patients with RA. Rheumatoid factor was present in 17 (53.1%) patients, antinuclear antibodies (ANA) were observed in 15 (48.4%) patients, and anti-rheumatoid arthritis nuclear antigens (RANA) in 22 (68.7%) patients; anti-SSA antibodies were confirmed in 3 (9.4%) patients and anti-SSB antibodies in 2 (6.2%) patients. None of the patients evidenced anti-U1RNP. Although keratoconjunctivitis sicca and xerostomia correlated significantly with the presence of rheumatoid factor, we found no relationship between these two conditions and ANA or anti-RANA antibodies. The high frequency of keratoconjunctivitis sicca and xerostomia in our RA patients is the expression of extra-articular involvement in this disease and is correlated with the presence of rheumatoid factor. ANA and anti-RANA antibodies may represent aspecific polyclonal activation in RA.

In order to evaluate the presence of antiphospholipid antibodies (aPL) in patients with systemic lupus erythematosus (SLE), we measured IgG and IgM anticardiolipin antibodies (aCL) in a group of out- and in-patients of the Rheumatology Division at the Catholic University of Rome. Lupus anticoagulant and VDRL were also measured in 30 patients. One hundred thirteen women and 7 men (mean age 38.5 years, mean disease duration 4.27 years) were studied. The control group consisted of 60 age and sex matched healthy subjects. aCL IgG and IgM were positive in 48 (40%) and 49 (40.8%) patients respectively. aCL IgG correlated positively with the activated partial thromboplastin time. aCL IgM correlated positively with immunoglobulins of the G and M classes and with circulating immune complexes, and negatively with the C4 fraction. aCL antibodies did not correlate with spontaneous abortion or neurologic and psychiatric disturbances, although in women with a history of abortion, aCL IgG concentration was correlated with the number of spontaneous abortions. The presence of aPL does not seem to indicate a subgroup of SLE patients. The occurrence of abortion and/or neurologic and psychiatric disturbances in SLE seems to point to a complex pathogenesis with aPL as one of the causative agents.

Nicotinamide (NCT) has been shown to be effective in preventing the onset of type 1 diabetes mellitus (IDDM) in mice with non-obese diabetic (NOD) and beta cell damage, mediated by the diabetogenic agents including streptozotocin. NCT therapy in man has been shown to have a beneficial effect on the remission phase of IDDM, and its use is safe. In this open pilot trial we therefore studied the effect of oral NCT administration on insulin secretion rate and islet-cell antibody (ICA) titres in IDDM high risk subjects. NCT (25 mg/10 kg bw) was administered in 6/13 high risk patients identified by a family screening programme. Those subjects tested after eight months without treatment showed a decreasing secretion in comparison to onset baseline (56,1 +/- 37.8 versus 35,5 +/- 12.2), whereas the treated subjects showed an increasing insulin secretion after treatment (26 +/- 10 versus 50.2 +/- 26.6), in spite of ICA persistence. Statistical analysis shows an increased insulin secretion in the treated group versus the untreated group (chi 2 = 3.899, P = 0.048). No side-effects were observed. We conclude that NCT may repair beta-cell function in high risk subjects too if damage is not too severe; furthermore, the effect seems not to be mediated by an immune mechanism.

Autoimmune thyroid disorders have been shown to occur in patients with connective tissue diseases. Hypothyroidism and thyrotoxicosis have been recognized in systemic lupus erythematosus (SLE). Moreover, a high prevalence of antithyroid antibodies has been found in patients with SLE. We studied thyroid function in a group of SLE female patients without a history or clinical diagnosis of thyroid disease and then correlated the prevalence of abnormal function test results with the laboratory indexes of active disease and with the presence of antithyroid antibodies. The SLE patients had significantly lower T4 levels than the controls. Basal TSH and TSH concentrations after TRH stimulation were significantly higher in patients with active SLE in comparison to both patients with inactive SLE and to controls. 45.5% of patients with active SLE presented antithyroid antibodies. Antithyroglobulin and antimicrosomal antibodies were not found in patients with inactive SLE nor in controls. Our results confirm the existence of a mild hypothyroidism in SLE that is clinically silent. The altered thyroid function appears to be dependent on the activity of the systemic autoimmune process.

Insulin dependent diabetes mellitus is an autoimmune disease with HLA-related genetic susceptibility. There is a latent phase before overt disease. During this phase islet cell antibodies (ICA) as a marker of humoral autoimmunity are detected and i.v. glucose tolerance test (IVGTT) is decreased. The aim of our work was to correlate IVGTT, HLA typing and ICA testing in all siblings of IDDM patients in order to identify high risk subjects (HRS). IVGTT showed significantly lower insulin levels in siblings vs controls (P less than 0.0001). This phenomenon could be caused by HLA unrelated genetic predisposition to low insulin secretion. Insulin level values of ICA+ siblings were lower than those of ICA- siblings, even if the difference was not significant.

We have studied 27 insulin-dependent diabetic patients since diagnosis for a period of six months; at diabetes onset and later on, ICA were found in 17 of them, whereas they were undetectable in 10 patients: age was remarkably homogeneous in the two groups. At diabetes onset, no significant differences were found in insulin requirement between ICA positive and ICA negative patients; however, six months after diagnosis, we observed that insulin requirement to keep metabolic control was significantly higher in ICA positive than in ICA negative subjects (0.515 +/- 0.2 U/Kg versus 0.22 +/- 0.15 U/Kg, p less than 0.001). Only one remission has been detected in ICA positive group (insulin requirement less than 0.25 U/Kg), while four ICA negative patients had complete remission and three had partial remission. ICA positive patients showed fasting C-peptide values higher than ICA negative (0.5 +/- 0.28 ng/ml versus 1.4 +/- 0.5 ng/m.; p less than 0.001, at rest; 1.1 +/- 0.6 ng/ml; versus 2.6 +/- 1.0 ng/ml, 6 minutes after stimulus; p less than 0.05). Our study suggests that presence and persistence of ICA may be considered an early and predictive marker for a worse beta cell function restoration resulting in a higher insulin requirement.

The authors report a case of an eight-years old child, who presented with transient Fanconi syndrome, mild renal failure and hypoplastic bone marrow. No recognized etiology of the Fanconi syndrome was demonstrated in the patient. Laboratory data and clinical course are consistent with the hypothesis of a tubulo-interstitial lesion caused, directly or through an abnormal immune response, by an unknown etiologic agent.

The authors investigated the incidence of thalassemia traits and hemoglobinopathies in western Liguria, where up to 70% of people comes from other italian regions, particularly from the South. The authors screened 442 primary school pupils in Albenga and Andora (Savona). Laboratory investigations permitted to detect 19 thalassemia trait carrier subjects (4.30% of the total examined): 12 of them were diagnosed heterozygous for beta-thalassemia, 6 for alpha-thalassemia, and 1 for Hb S. Authors would underline that more than half of the screening positive subjects resulted carrier of beta-thalassemia or Hb S trait, both potentially able to give origin to severe diseases: homozygous beta-thalassemia, sickle cell anemia, and beta-thalassemia/Hb S double heterozygosity.

The clinical and immunological characteristics of myasthenia gravis (MG) patients without detectable anti-Acetylcholine Receptor (anti-AChR) antibody were studied. Sixty anti-AChR negative MG patients were compared with 287 anti-AChR positive cases. Significant differences were found with respect to the sex incidence, the disease severity and the thymic pathology, while the age at the onset of the disease, the presence of other auto-antibodies and the efficacy of medical treatments were similar in the two groups of patients. Anti-AChR-negative MG could have pathogenetic mechanisms different from the antibody-positive disease.