Experimental colitis in IL-10-deficient mice ameliorates in the absence of PTPN22.

Interleukin (IL)-10 plays a key role in controlling intestinal inflammation. IL-10-deficient mice and patients with mutations in IL-10 or its receptor, IL-10R, show increased susceptibility to inflammatory bowel diseases (IBD). Protein tyrosine phosphatase, non-receptor type 22 (PTPN22) controls immune cell activation and the equilibrium between regulatory and effector T cells, playing an important role in controlling immune homoeostasis of the gut. Here, we examined the role of PTPN22 in intestinal inflammation of IL-10-deficient (IL-10-/- ) mice. We crossed IL-10-/- mice with PTPN22-/- mice to generate PTPN22-/- IL-10-/- double knock-out mice and induced colitis with dextran sodium sulphate (DSS). In line with previous reports, DSS-induced acute and chronic colitis was exacerbated in IL-10-/- mice compared to wild-type (WT) controls. However, PTPN22-/- IL-10-/- double knock-out mice developed milder disease compared to IL-10-/- mice. IL-17-promoting innate cytokines and T helper type 17 (Th17) cells were markedly increased in PTPN22-/- IL-10-/- mice, but did not provide a protctive function. CXCL1/KC was also increased in PTPN22-/- IL-10-/- mice, but therapeutic injection of CXCL1/KC in IL-10-/- mice did not ameliorate colitis. These results show that PTPN22 promotes intestinal inflammation in IL-10-deficient mice, suggesting that therapeutic targeting of PTPN22 might be beneficial in patients with IBD and mutations in IL-10 and IL-10R.

Juvenile dermatomyositis: A report of three cases.

Juvenile dermatomyositis (JDM), an autoimmune idiopathic myositis, is characterized by rash and proximal muscle weakness. Immunohistopathology typically shows perivascular inflammatory infiltrate with predominance of CD4+ T lymphocytes, perifascicular atrophy, and upregulation of major histocompatibility complex class I. JDM has been attributed to a humoral-driven muscle microangiopathy probably implicating the type I interferon pathway. Tubulo-reticular inclusions present in endothelial cell of muscle are biomarkers of interferon exposure, and so may be an indirect data of this myopathy especially in the absence of rash and inflammatory infiltrate. We report on three patients in which electron microscopy solves the differential diagnosis among infantile myositis showing peculiar inclusions.

Ultrastructural changes in dysferlinopathy support defective membrane repair mechanism.

BACKGROUND: The dysferlin gene has recently been shown to be involved in limb girdle muscular dystrophy type 2B and its allelic disease, Miyoshi myopathy, both of which are characterised by an active muscle degeneration and regeneration process. Dysferlin is known to play an essential role in skeletal muscle fibre repair, but the process underlying the pathogenetic mechanism of dysferlinopathy is not completely understood. AIMS: To define both specific alterations of muscle fibres and a possible sequential mechanism of myopathy development. METHODS: A histological, immunohistochemical, and ultrastructural analysis of 10 muscle biopsies from patients with molecularly diagnosed dysferlinopathy. RESULTS: An inflammatory response was seen in most of the muscle biopsies. The immunohistochemical pattern demonstrated active regeneration and inflammation. Non-necrotic fibres showed alterations at different submicroscopic levels, namely: the sarcolemma and basal lamina, subsarcolemmal region, and sarcoplasmic compartment. In the subsarcolemmal region there were prominent aggregations of small vesicles, probably derived from the Golgi apparatus, which consisted of empty, swollen cisternae. In the sarcolemma there were many gaps and microvilli-like projections, whereas the basal lamina was multilayered. CONCLUSIONS: The histopathological, immunohistochemical, and ultrastructural data show that dysferlinopathy is characterised by a very active inflammatory/degenerative process, possibly associated with an inefficient repair and regenerative system. The presence of many crowded vesicles just beneath the sarcolemma provides submicroscopical proof of a defective resealing mechanism, which fails to repair the sarcolemma.

Human cytomegalovirus structural components: intracellular and intraviral localization of p28 and p65-69 by immunoelectron microscopy.

Using specific monoclonal antibodies, we have localized two structural proteins (p65-69 and p28) of human cytomegalovirus in infected cells and in virions and/or virus-related particles by immunoelectron microscopy using protein A-gold. Protein p65-69 is present in some roundish structures in the nuclei, often in contact with the viroplasm, and in the cytoplasm, exclusively within the dense body matrix. Protein p28 is present only in the outline of cytoplasmic capsids, and reaches the highest density in the large aggregates of virions and dense bodies which are particularly numerous during the late phases of the viral replication cycle.

Anti-TCR-V beta 6 breaks tolerance in female AKR, Mlsa mice inducing foetal lethality.

Immunisation with anti-TCR-V beta 6 of female AKR mice prior to and during syngeneic pregnancy resulted in neonatal lethality and eventually in abortion or foetal resorption. The sera of the hyperimmunised mothers were shown to have anti-H-2k and anti-Mlsa autoantibodies and were cytotoxic to H-2k targets in vitro and also blocked Mlsa-induced mixed lymphocyte reactions. These observations are discussed herein.

Anti-Mlsa-like effect of CBA/J anti DBA2 antibody in in vitro MLRs between Mls incompatible combinations.

Antisera from CBA/J (H-2k,Mlsa) mice hyperimmunised with DBA2 (H-2d,Mlsa) and/or AKR (H-2k,Mlsa) splenocytes, can block in vitro MLRs against Mlsa determinants. These two antisera are furthermore specifically cytotoxic against targets expressing H-2 components but not against Mlsa-bearing targets. In these experimental models the anti-Mlsa-like effects of CBA/J anti-DBA2 and CBA/J anti AKR antibodies seem to be associated with an autoreactive immune response in CBA/J mice elicited by DBA2 and AKR splenocytes, respectively. In this report we propose that anti-Mlsa antibodies can also be generated in a situation in which Mlsa is presented as 'altered self' in conjunction with allo-determinants.

The inheritance of a Macaca fascicularis red cell antigen detected by CAMPATH-1 antibody.

CAMPATH-1 monoclonal antibody is reactive with human lymphocytes and monocytes and it has been shown to bind to antigens on the red cells of a number of primate species, including Macaca fascicularis. Our study within a closed colony of breeding M. fascicularis monkeys has confirmed this finding, and shown that the antibody identified a single red cell antigen inherited in Mendelian fashion as a dominant character. We have, further, confirmed that the antigen is present on blood lymphocytes, even in animals whose red cells are negative. This CAMPATH-1 antigen can therefore serve as a useful red cell marker in experiments involving bone marrow transplantation or blood transfusion.

Pharmacological preconditioning of ischemic heart disease by low-dose dipyridamole.

Fourteen patients affected with coronary artery disease underwent two consecutive dipyridamole echocardiographic stress tests, in basal conditions and after repeated low doses of intravenous dipyridamole, following the observation that pulse increases in adenosine plasma levels due to repeated intravenous administration of dipyridamole mimic the mechanism of ischemic preconditioning. Echocardiographic, electrocardiographic, haemodynamic parameters, and adenosine plasma levels were measured. After the second test, six patients were completely negative, and in those eight still positive the onset of dyssynergy was delayed.

Sneddon syndrome, arylsulfatase A pseudodeficiency and impairment of cerebral white matter.

We describe a 11 year-old-boy with Sneddon syndrome, confirmed by skin biopsy, and MR evidence of diffuse cerebral hyperintensity of white matter; he also suffered from pre-perinatal hypoxic-ischemic distress. Arylsulfatase A activity was found reduced because of arylsulfatase A pseudodeficiency. We suggest that the association of pre-perinatal distress, Sneddon syndrome and arylsulfatase A pseudodeficiency is responsible for the diffuse impairment of cerebral white matter, never reported in Sneddon syndrome and similar to described cases of delayed posthypoxic demyelination and arylsulfatase A pseudodeficiency.

Light and electron microscopy investigation of glycoconjugates of rat hippocampus by lectin-gold technique.

The distribution of glycoconjugates in rat hippocampus was investigated by light and electron microscopy using gold-labelled lectins with different sugar specificities: ConA, WGA, PNA and LTA. A morphological correlation with cytochemical data was performed, and revealed the presence of intensely-stained (dark), unstained (light) and weakly-stained (intermediate) neurons both in Ammon's horn and in the dentate gyrus. The glycoconjugates are located in the nucleus, the perikaryal cytoplasm and the cytoskeleton of axons and dendrites: they are probably involved in the mechanisms of transport towards the synaptic membrane. The presence or absence of glycoconjugates corresponds to the particular ultrastructural aspect of the cell. This suggests the existence of different functional states of the neurons, probably correlated with the synthesis of neurotransmitter precursors or receptors.

Ultrastructural aspects of ageing rat hippocampus and effects of L-acetyl-carnitine treatment.

The ageing rat hippocampus undergoes ultrastructural changes, including the loss of axosomatic synapses of the granule cells. These synapses are supposed to take part in a feed-back regulation of granule cell activity, as they are inhibitory terminals of interneurons which receive afferences from the granules themselves via the giant synapses formed by the collaterals of the mossy fibres. In the present study the authors performed a quantitative analysis of axosomatic and giant synapses at the ultrastructural level in aged rats as compared with young animals. In aged rats a decrease both in axosomatic synapses and in giant synapsis vesicles was found, giving further support to the postulated feed-back mechanism. Both young and old rats were treated with L-acetyl-carnitine, a drug which favours the synthesis of acetylcholine, the main neurotransmitter deficient in old age. In aged rats the drug restored a normal number of both axosomatic synapses and giant bouton vesicles. The authors hypothesize that the drug, by a cholinergic-type mechanism, restores the excitatory afferences to the granule whose axon would thus form normal giant boutons with the interneuron, reestablishing the feed-back regulation. In young rats the drug induced a decrease only of the axosomatic synapses, suggesting that an "over-excitation" might impair the information to the local-circuit neurons, thus interrupting feed-back control.

Ultrastructural aspects of aging rat hippocampus after long-term administration of acetyl-L-carnitine.

In aged rats a decrease in axosomatic synapses of granule cells as well as a decrease in the number of synaptic vesicles of giant synapses was found. These phenomena were supposed to be correlated on the basis of a feed-back circuit existing at the level of the dentate gyrus. In fact the axosomatic synapses of the granules are inhibitory gamma-aminobutyric acid-ergic terminals of interneurons. Interneurons receive excitatory afferences from granules via the giant synapses of the mossy fibre collaterals. This results in a feed-back regulation of granule cell activity. The long-term administration of acetyl-L-carnitine to aged rats restores a synaptic pattern comparable to that of young rats. This effect on synaptic plasticity is transient.

Effects of alprostadil on blood rheology and nucleoside metabolism in patients affected with lower limb chronic ischaemia.

The acute (0.57 microg/kg i.v. in 2 hours) and long-term (0.57 microg/kg i.v. in 2 hours for 5 days over 4 weeks) effects of the PGE1 analogue alprostadil were studied in patients affected with intermittent claudication. Whole Blood Viscosity (WBV), Whole Blood Filterability (WBF), haematocrit (Htc) and fibrinogen plasma concentration, were studied together with P50, 2,3-diphosphoglycerate, and adenosine plasma levels. Moreover, in the long-term study, pain-free (PFWD) and maximal walking distance (MWD) were measured. Single alprostadil infusion induced an improvement in WBV, WBF, and oxygen transport, and an increase in adenosine plasma levels. Long-term alprostadil administration produced a decrease in WBV only, without significant changes in WBF, Htc, fibrinogen, P50, 2,3-diphosphoglycerate, also inducing a significant prolongation of PFWD and MWD. The possibility is suggested that pulse rises in adenosine plasma levels play a role in the effects of chronic alprostadil administration, maybe in a way similar to that observed in the phenomenon of ischaemic preconditioning,

[Congenital transient mechanobullous dermatosis (Bart's syndrome). A clinical case and review of the literature]. / Congenital transient mechanobullous dermatosis (sindrome di Bart). Un caso clinico e review della letteratura.

Bart's syndrome or congenital transient mechano-bullous dermatosis is one of the lesser known presentations of epidermolysis bullosa. It is characterized by congenital skin defects and by a tendency for blistering of the skin and sometimes of mucous membranes and sometimes associated with nail deformities, all of which remitted within in a few years. A neonate is described and compared with similar patterns from the literature.

Thymosin-alpha 1 (Zadaxin) enhances the immunogenicity of an adjuvated pandemic H1N1v influenza vaccine (Focetria) in hemodialyzed patients: a pilot study.

BACKGROUND: Although influenza vaccination is widely recommended for immunosuppressed people, the same immune dysfunction that can increase the risk of contracting influenza might also compromise vaccine effectiveness, especially during pandemics. Clinical data have highlighted the role of adjuvants in improving vaccine efficacy. As uremic patients are especially vulnerable to infections, it is recommended that they should be vaccinated yearly against influenza. This paper presents the results of a pilot clinical trial, conducted in hemodialyzed patients with an adjuvated pandemic H1N1v influenza vaccine alone and combined with Thymosin-alpha 1. METHODS: Subjects were subdivided into 3 treatment groups receiving: the adjuvated pandemic influenza vaccine (Focetria) only (first treatment group), and the Vaccine+Thymosin alpha 1 (Zadaxin) at a dose of 3.2 and 6.4 mg (second and third treatment groups respectively). The immunoresponse was assessed on days 0, 21, 42, 84 and 168 after vaccine administration by means of Hemagglutination Inhibition (HI), Microneutralization (MN) and Single Radial Hemolysis (SRH) assays. The CHMP regards HI as the gold standard test to evaluate the immune response to influenza vaccines before influenza vaccines are licensed. The CHMP criteria are slightly different in adults (18-60-year-old subjects) and the elderly (>60 years old). Indeed, 40% of seroconversion, 70% of subjects seroprotected 21 days after vaccination, and a 2.5-fold increase in GMR (Geometric Mean Ratio) are required in adults, while in the elderly, the corresponding threshold values are: 30%, 60% and a 2-fold increase. All these criteria must be met for the licensing of a pandemic influenza vaccine. Safety evaluation was performed by means of Adverse Event (AE) recording, laboratory assays (hematology and chemistry), electrocardiogram, and assessment of vital signs. RESULTS: Three populations were considered: Intention-To-Treat (ITT) (94 patients), Per Protocol (PP) (82 patients), and Safety population (99 patients). With regard to the Geometric Mean Titer (GMT) and the Geometric Mean Ratio (GMR) of HI on Day 21 in the ITT population, both "Vaccine+Thymosin alpha 1" groups presented better results than the "Vaccine only" group. A large proportion of ITT patients in the two Vaccine+Thymosin alpha 1 groups achieved seroconversion by Day 21. On Day 42, the decrease in the GMT of HI was greater in the Vaccine+Thymosin alpha 1 groups than in the vaccine only group. Similar results were obtained in the PP population. The CHMP criteria were fully met in the groups treated with Vaccine+Thymosin alpha 1. No AE was found to be related to Thymosin alpha 1 nor to the Focetria vaccine. CONCLUSIONS: Although further studies in larger hemodialyzed populations are necessary, it can be concluded that Thymosin alpha 1 enhanced the immunogenicity of the pandemic influenza vaccine used. Moreover, it proved safe and well tolerated, and did not affect hematology or blood-chemistry values.