Niveles de Interferón Tipo I en pacientes con Lupus Eritematoso Sistémico / Type I interferon levels in patients with systemic lupus erythematosus

Introducción: El interferón (IFN) tipo I es una citoquina que juega un rol fundamental en la patogenia del Lupus Eritematoso Sistémico (LES). Diferentes niveles de esta citoquina podrían explicar la heterogeneidad de esta patología y ser útil para evaluar la actividad de la misma. Objetivos: Determinar los niveles de IFN tipo I sérico en pacientes con LES y evaluar su utilidad como biomarcador de actividad. Material y Métodos: 16 pacientes con LES (ACR 1997) y 16 controles. Métodos: Actividad de la enfermedad (SLEDAI-2K), daño orgánico (SLICC), IFN tipo I (HEK-Blue-IFNα/β), anticuerpos anti-DNAdc (Inmunofluorescencia Indirecta), anticuerpos anti-ENA (ELISA), C3-C4 (Inmunoturbidimetría). Estadística: InfoStat/Instat/MedCalc. Valores de p<0,05 fueron considerados estadísticamente significativos. Resultados: Se observó un aumento de la concentración de IFN en el grupo LES con respecto al control (p<0,05). Los pacientes con valores de IFN superiores al punto de corte, se asociaron con la presencia de anticuerpos anti-DNAdc (OR:13,33; p<0,05). Pacientes con hipocomplementemia y aquellos con puntaje de SLEDAI-2K mayor a 8 presentaron mayores niveles de IFN comparados con pacientes con complemento normal y menor puntaje de índice, respectivamente (p<0,05). Conclusiones: Estos resultados sugieren la importancia que podría tener la determinación de IFN tipo I para el monitoreo de la actividad del LES.

Introduction: Type I interferon (IFN) is a cytokine that plays a fundamental role in the pathogenesis of Systemic Lupus Erythematosus (SLE). Different levels of this cytokine could explain the heterogeneity of this pathology and be useful to evaluate its activity. Objectives: To determine the serum type I IFN levels in patients with SLE and evaluate its usefulness as a biomarker of activity. Material and Method: 16 patients with SLE (ACR 1997) and 16 controls. Methods: Disease activity (SLEDAI-2K), organ damage (SLICC), type I IFN (HEK-Blue-IFNα/β), anti-dsDNA antibodies (Indirect Immunofluorescence), anti-ENA antibodies (ELISA), C3-C4 (Immunoturbidimetry). Statistics: InfoStat/Instat/MedCalc. P values <0.05 were statistically significant. Results: An increase in IFN concentration was observed in the SLE group respect to the control (p <0.05). Patients with IFN values above the cut-off point were associated with the presence of anti-dsDNA antibodies (OR: 13.33; p<0.05). Hypocomplementemic patients and those with a SLEDAI-2K score greater than 8 had higher IFN levels compared to patients with normal complement and a lower index score, respectively (p<0.05). Conclusions: These results suggest the importance that the determination of IFN type I could have for the monitoring of SLE activity.

Properties of (Ga1-x In x )2O3 over the whole x range.

Using density-functional ab initio theoretical techniques, we study (Ga1-x In x )2O3 in both its equilibrium structures (monoclinic [Formula: see text] and bixbyite) and over the whole range of composition. We establish that the alloy exhibits a large and temperature-independent miscibility gap. On the low-x side, the favored phase is isostructural with [Formula: see text]-Ga2O3; on the high-x side, it is isostructural with bixbyite In2O3. The miscibility gap opens between approximately 15% and 55% In content for the bixbyite alloy grown epitaxially on In2O3, and 15% and 85% In content for the free-standing bixbyite alloy. The gap, volume and band offsets to the parent compound also exhibit anomalies as function of x. Specifically, the offsets in epitaxial conditions are predominantly type-B staggered, but have opposite signs in the two end-of-range phases.

Heat shock proteins (HSPs) based anti-cancer vaccines.

The importance of HSPs themselves in antigen presentation and cross-presentation remains controversial. Most studies agree that as part of their molecular chaperone function, HSPs can bind and present tumor associated antigens to professional antigen presenting cells through MHC class I and class II molecules, leading to the activation of anti-tumor CD8+ and CD4+ T cells. The regulation of the innate and adaptive immune responses by HSPs is still a matter of intense research. HSPs are seen as important anticancer vaccine adjuvants. They are used through different delivery systems: HSPs/antibodies, peptide/protein-HSP complexes, tumor antigen/HSP gene fusion, viral peptides/HSP complexes or gene fusion, viral proteins/bacterial HSP fusion. In preclinical models different administration routes, subcutaneous, intradermal, intramuscular or even peroral (under special conditions) can be used, and the animal toxicities are non-significant. The HSP-based vaccines can induce specific and non-specific cellular immune responses all of which are important to induce tumor rejection. In addition, the antibodies generated after vaccination are emerging as important protagonist in the antitumoral response. This response is significantly enhanced when the suppressive tumor microenvironment and the immune suppressing effector cells are blocked. Several clinical studies have been carried out and are ongoing, immunizing cancer patients with autologous tumor derived HSP-peptide complexes (HSPPCs). The most promising results have been observed in patients with melanoma and renal clear cell cancer without advanced disease. There are clinical trials with HSP-based anticancer vaccines other than with HSPPCs (including patients with non-Hodgkin lymphoma, high-grade transitional cell carcinoma of the bladder, high-grade cervical dysplasia, etc).

Chemokine response induced by Chlamydia trachomatis in prostate derived CD45+ and CD45- cells.

The role of innate cells and their receptors within the male genital tract remains poorly understood. Much less is known about the relative contribution of different genital tract cells such as epithelial/stromal cells and resident leucocytes. In this study, we examined innate immune responses to Chlamydia trachomatis by prostate epithelial/stromal cells and prostate resident leucocytes. Murine prostate primary cultures were performed and leucocyte and epithelial/stromal cells were sorted based on surface protein expression of CD45 by magnetism-activated cell sorting or fluorescence-activated cell sorting. Prostate derived CD45- and CD45+ cells were infected with C. trachomatis and chemokine secretion assayed by ELISA. Similar experiments were performed using prostate CD45+ and CD45- cells from myeloid differentiation factor 88 (Myd88(-/-)) mice or toll-like receptor (Tlr2(-/-)) and Tlr4(mutant) double-deficient mice. Moreover, a TLR-signalling pathway array was used to screen changes in different genes involved in TLR-signalling pathways by real-time PCR. Prostate derived CD45- and CD45+ cells responded to chlamydial infection with the production of different chemokines. Both populations expressed genes involved in TLR signalling and required to respond to pathogen-associated molecular patterns and to C. trachomatis infection. Both populations required the adaptor molecule MYD88 to elicit chemokine response against C. trachomatis. TLR2-TLR4 was essential for chemokine production by CD45+ prostate derived cells, but in their absence, CD45- cells still produced significant levels of chemokines. We demonstrate that C. trachomatis is differentially recognised by prostate derived CD45+ and CD45- cells and suggest that diverse strategies are taking place in the local microenvironment of the host in response to the infection.

Autoimmune prostatitis: state of the art.

The prostate is one of the main male sex accessory glands and the target of many pathological conditions affecting men of all ages. Pathological conditions of the prostate gland range from infections, chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS) of a still unknown aetiology to benign hyperplasia and cancer. CP/CPPS is one of the most prevalent diseases in the urologic clinic and affects men younger than 50 years old. A significant advance in the understanding of CP/CPPS was made when an autoimmune response against prostate antigens was revealed in a considerable number of patients. During the last 30 years, extensive work has been done regarding the development and characterization of different rodent models of experimental autoimmune prostatitis (EAP). It has been demonstrated that tolerance to prostate antigens can be disrupted in some strains of rats and mice and cellular and humoral responses to prostate antigens are elicited. A Th1 pattern has been described and the cellular response seems to be the major pathogenic mechanism involved. Immune cells infiltrate the gland and induce prostate lesions. The genetic background and hormonal imbalance are factors that could contribute to the onset of the disease in susceptible young males. Moreover, spontaneous autoimmune prostatitis could also occur with advanced age in susceptible strains. In this review, we summarize the current knowledge regarding rodent models of EAP and the immunological alterations present in CP/CPPS patients. We also discuss the reliability of these experimental approaches as genuine tools for the study of human disease.

Identification of rat prostatic steroid binding protein (PSBP) as an immunosuppressive factor.

Prostatic steroid binding protein (PSBP) is the major protein produced ( approximately 20% of the total cytosolic protein) and secreted into the seminal fluid by the rat ventral prostate but its physiological function has not been elucidated yet. Since PSBP is secreted into the seminal fluid (which is itself a potent immunosuppressor) and has strong homology with uteroglobin (which possess an important anti-inflammatory function) our aim was to determine what effect, if any, PSBP would have on the immune system. With that purpose in mind we performed mononuclear cell cultures in the presence or absence of purified PSBP and analysed the effect of this protein on different functional parameters. PSBP inhibits the mitogen-induced proliferation of normal rat spleen mononuclear cells (MNC) specifically and in a dose-dependent manner. It reduces the production of IL-2 and the expression of its receptor (analysed by flow cytometry) which are important events for lymphocyte proliferation. Also, PSBP was able to inhibit OVA-specific proliferation of lymph node cells from previously primed animals. The immunosuppressive effect of PSBP is not due to an inherent toxic effect to the cells, since the cell viability was kept intact at the different times of culture studied. We also analysed the effect of rat PSBP on mitogen-induced proliferation of mouse spleen and human blood MNC. The proliferation was strongly abolished in a dose-dependent and non-species specific fashion. Moreover, PSBP strongly inhibits the human mixed lymphocyte reaction. Taken together, the present data support evidence for a new type of function for PSBP. We report that PSBP is a potent immunosuppressor factor and we describe its effect on the immune function in vitro. Here, we discuss the possible implications of these findings in the protection of sperm from immunologic damage in the feminine reproductive tract.

Peritoneal antigen-presenting cells pulsed in vivo with myelin basic protein induce the suppression of experimental autoimmune encephalomyelitis (EAE) in Wistar rats.

Suppression of Experimental Autoimmune Encephalomyelitis (EAE) can be achieved by i.p. administration of soluble myelin basic protein (MBP) in adult Wistar rats before the immunization. In the present work, we analyze the role of peritoneal antigen-presenting cells (APC) in the induction of tolerance to EAE. Peritoneal cells (PC) pulsed in vivo with MBP were obtained from rats that had been intraperitoneally injected 2 h previously with soluble MBP (MBP-PC) and then inoculated in recipient rats before the induction of EAE. Our findings show that the i.p. treatment of the animals with MBP-PC before the immunization was able to diminish the incidence and severity of the disease, reduce the histological alterations, abrogate the proliferative response against MBP and change the pattern of the humoral response to MBP. Moreover, when spleen mononuclear cells (MNC) from tolerant animals were cultured together with spleen MNC from sick animals, a dose-dependent inhibition of the proliferative response was observed, arguing for the presence of a regulatory cell population in the tolerant animals. It is also demonstrated that the MBP-PC are activated and their capability of inducing suppression of EAE is highly associated with the enhanced expression of MHC class II IA molecule. Our results show that peritoneal cells pulsed in vivo with MBP are able to induce tolerance and suggest that the up-regulation of MHC class II on MBP-PC is a necessary event for tolerance induction in our model.

Prostatein (or rat prostatic steroid binding protein) is a major autoantigen in experimental autoimmune prostatitis.

Experimental autoimmune prostatitis (EAP) is a disease that could be considered an experimental model of human non-bacterial prostatitis. In this experimental model, male rats are intradermally immunized with a saline extract of male sex accessory glands (RAG) in an adequate adjuvant. The prostatitis observed in the immunized animals develops as a consequence of the immune response against RAG antigens, and the histological lesion is strikingly similar to the pattern of prostatic inflammation observed in the human disease. In this study, we purified one of the prostatic autoantigens recognized by the autoantibodies in our model. Amino acid sequence analysis identified the purified protein as prostatein or rat prostatic steroid binding protein, a member of the uteroglobin superfamily. Prostatein was recognized not only by the humoral autoimmune response, but also by the cellular autoimmune response. Certainly, the DTH response and lymph node cell proliferative assays against prostatein in immunized animals yielded positive results. Prostatein is not only the target of the autoimmune response in animals immunized with the whole extract, but also an inducing antigen of the disease. Purified prostatein, when incorporated to an adequate adjuvant, elicited cellular and humoral autoimmune response and lesion in the prostate gland. The identification of one of the target antigens in autoimmune prostatitis has provided a further refinement and characterization of our model, which could serve for a better understanding of the aetiology, pathogenesis and pathophysiology of non-bacterial prostatitis.

Suppression of experimental autoimmune encephalomyelitis (EAE) by intraperitoneal administration of soluble myelin antigens in Wistar rats.

Intraperitoneal (i.p.) treatment of Wistar rats with bovine myelin (BM) or myelin basic protein (MBP) previously to immunization with BM-CFA showed a diminished incidence and severity of experimental autoimmune encephalomyelitis (EAE) (2/13 and 0/7, respectively) when compared with rats immunized with BM-CFA (11/17) or i.p. treated with ovalbumin (2/4). Concomitantly, animals treated with BM or MBP exhibited a marked reduction of proliferative response to MBP which was highly positive when spleen mononuclear cells from nontreated and ovalbumin treated animals were assayed. Rats that were treated with MBP before immunization produce IgA, IgM, total IgG and subclasses of IgG, IgG2a, IgG2b, IgG2c specific for MBP in similar levels than those observed in nontreated immunized animals. However, a higher incidence and level of IgG1 was observed in MBP treated rats, meanwhile rats i.p. treated with total BM showed a highly reduced humoral response. The herein presented results show that i.p. treatment with low amounts of soluble forms of myelin antigens markedly reduced the clinical symptoms of the disease, the histological alterations, the cellular proliferative response to MBP, and produced changes in the autoimmune humoral response.

Protective immunity induced by a Yersinia enterocolitica serovar 0:8 cellular extract.

The purpose of this study was to investigate the protective power of a cellular extract (CE) from Y. enterocolitica 0:8 grown in condition of expression of chromosomal antigens. Mice were immunized by s.c. route and challenged with: 0 LD50 (1 x 10(4) CFU/ml). Immunoblotting showed that CE-specific serum reacted with several CE antigens. Prominent bands, of molecular weights 60 and 35.5, were present in cytoplasmic and membrane fraction, respectively. The lipopolysaccharide (LPS) was detected in CE. These findings suggest that chromosomally-encoded antigens present in CE may induce protection against Y. enterocolitica infection. Both humoral and cellular immune response contribute to protection in mice.

Experimental autoimmune encephalomyelitis: antigen-induced inhibition of biochemical and immunohistological alterations.

A comprehensive biochemical, immunological, and histological study was undertaken during suppression of experimental autoimmune encephalomyelitis (EAE) induced by antigen-specific inhibition of the immune response. Pretreatment of Wistar rats by intraperitoneal administration of low doses of saline-soluble bovine myelin or myelin basic protein (MBP) but not with ovalbumin suppresses the appearance of the clinical symptoms of EAE induced by sensitization with bovine myelin in complete Freund's adjuvant. Analysis of the central nervous system (CNS) of animals pretreated with MBP or whole myelin shows inhibition of the diminution of MBP and 2',3'-cyclic nucleotide 3'-phosphohydrolase (CNPase) activity observed in the EAE animals or in rats pretreated with ovalbumin. With respect to the CNS lipid content, these suppressive treatments abolish the increase in esterified cholesterol and partially revert the diminution in the content of cerebrosides and total cholesterol characteristic of the acute stage of the disease. Concomitantly, meningeal and parenchymal infiltration with mononuclear cells and deposits of immunoglobulins in the infiltrated regions as well as in spinal cord motor neurons were reduced. Analysis of the humoral response to myelin antigens shows that all EAE as well as treated animals developed antibodies to MBP and other myelin proteins. However, a higher incidence and level of these antibodies was observed in nontreated EAE animals and MBP- and ovalbumin-treated rats, while rats treated with total bovine myelin showed a highly reduced humoral response. The present results indicate that intraperitoneal treatment with soluble forms of myelin antigens, concomitant with the suppression of the clinical symptoms of the disease, markedly reduces the biochemical and histological alterations occurring in EAE animals and produces changes in the autoimmune humoral response.

Autoantibodies against rat prostate antigens. Association of specific IGG2b and IGG2c with the DTH response.

Although autoimmune response against most tissues in the body has been extensively described, very little is known about autoimmune response against prostate antigens either in humans or animals. In this work we studied the autoimmune response elicited against rat prostate (RP) in Wistar rats immunized with a chemically modified extract of syngeneic male sex accessory glands (MRAG). We observed that one immunization was enough for the induction of positive delayed-type hypersensitivity test (DTH), which was higher on day 15 than on day 30. It was also enough to induce IgG autoantibodies to RP although a second injection was necessary to obtain a more frequent occurrence and a greater reactivity. The autoantibodies against RP were directed mainly to the cytosolic fraction and reacted at least with two molecules of 43 and 20 KD. Sera obtained on days 30 and 45 showed presence of specific IgG, IgA and IgM. Specific IgG2b and IgG2c were found on both days. On day 30 none of the sera presented IgG2a anti-RP, while on day 45 only 38% of the sera were considered positive for this isotype. No IgG1 anti-RP was detected in any serum of either bleeding. Direct immunofluorescence staining showed intense immunofluorescence in prostate epithelium, mainly in the apical zone of the gland, in animals that had received two immunizations with MRAG-CFA. No positive staining was seen in prostates obtained on day 30 after just one immunization, in sections of normal prostates or in sections of other rat organs. Our data indicate that the main isotypes involved in this autoimmune phenomenon are IgG2b and IgG2c. A strong association between the cellular autoimmune response measured by the DTH response and the IgG2b and IgG2c isotype was found at early stages of the disease. Since the DTH response and the IgG2b isotype have been previously associated with Th1-like activity in rats, our results suggest that Th1-like cells could be playing an active role in early stages of this disease.

Effects of thymus supernatants on the phenotype of different subsets of peritoneum antigen-presenting cells.

Peritoneal cells (PC) obtained 2 h subsequent to intraperitoneal (i.p.) injection of low doses (200 micrograms) of a purified fraction of rat male accessory glands (FI-RAG) are phenotypically and functionally different from those obtained 24 h after i.p. injection. In fast, PC obtained 2 h after FI-RAG injection are mainly IE+ and are involved in inducing specific suppression to RAG. In contrast, PC obtained 24 h after FI-RAG injection are mainly IA+ and capable of inducing specific response to RAG. For their induction, IA+ PC require cells within or recently derived from bone marrow. In order to analyze the mechanisms involved in IA+ bone marrow-dependent cell generation in the peritoneum, we studied the distribution of FI-RAG following i.p. injection. It was established that FI-RAG is found mainly in the thymus 2 h after injection and remains there for at least 24 h. Subsequently, we analyzed, in 4 groups of rats, the influence of thymic culture supernatants on the phenotype of cells appearing in the peritoneal cavity 2 h after FI-RAG injection. An increase in IA+ PC was observed 2 h after i.p. injection of FI-RAG in animals that had received either supernatants from normal thymic cells cultured with FI-RAG or those from thymic cells taken from animals injected with FI-RAG 2 h prior to being killed. Supernatants of thymic cells from animals injected with FI-RAG 24 h prior to being killed or from normal thymic cells do not increase the percentage of IA+ PC.(ABSTRACT TRUNCATED AT 250 WORDS)