Self-reactive T cells induce and perpetuate chronic relapsing arthritis.

Background: CD4 T cells play a central role during the early stages of rheumatoid arthritis (RA), but to which extent they are required for the perpetuation of the disease is still not fully understood. The aim of the current study was to obtain conclusive evidence that T cells drive chronic relapsing arthritis.

Methods: We used the rat pristane-induced arthritis model, which accurately portrays the chronic relapsing-remitting disease course of RA, to examine the contribution of T cells to chronic arthritis.

Brain stem audiometry may supply markers for diagnostic and therapeutic control in psychiatry.

The purpose of the present study is to try an alternative way of analyzing the ABR (Auditory Brainstem Response). The stimuli were complex sounds (c-ABR) as used in earlier studies. It was further aimed at corroborating earlier findings that this method can discriminate several neuropsychiatric states.

Thalamocortical abnormalities in auditory brainstem response patterns distinguish DSM-IV bipolar disorder type I from schizophrenia.

Background: Bipolar disorder type I (BP-I) belongs to a spectrum of affective disorders that are expressed in many different ways and therefore can be difficult to distinguish from other conditions, especially unipolar depression, schizoaffective disorder, schizophrenia (SZ), but also anxiety and personality disorders. Since early diagnosis and treatment have shown to improve the long-term prognosis, complementary specific biomarkers are of great value. The auditory brainstem response (ABR) has previously been applied successfully to identify specific abnormal ABR patterns in SZ and Asperger syndrome.

Boosters of a therapeutic HIV-1 vaccine induce divergent T cell responses related to regulatory mechanisms.

Therapeutic human immunodeficiency virus (HIV) vaccines aim to reduce disease progression by inducing HIV-specific T cells. Vacc-4x are peptides derived from conserved domains within HIV-1 p24 Gag. Previously, Vacc-4x induced T cell responses in 90% of patients which were associated with reduced viral loads.

Intradermal vaccination of HIV-infected patients with short HIV Gag p24-like peptides induces CD4 + and CD8 + T cell responses lasting more than seven years.

Background: Vacc-4x contains 4 HIV p24-like short peptides. In a previous phase II trial this immunized 90% of 38 patients on antiretroviral treatment (ART) after intradermal delivery in conjunction with local granulocyte-macrophage colony-stimulating factor (GM-CSF) as adjuvant. In this study, 22 responders were retested for cellular memory at a median 7.

Cartilage oligomeric matrix protein induction of chronic arthritis in mice.

Objective: To develop a new mouse model for arthritis using cartilage oligomeric matrix protein (COMP) and to study the role of major histocompatibility complex (MHC) and Ncf1 genes in COMP-induced arthritis (COMPIA).

Methods: Native (pentameric) and denatured (monomeric) COMP purified from a rat chondrosarcoma was injected into mice with Freund's adjuvant to induce arthritis. C3H.

A new arthritis therapy with oxidative burst inducers.

Background: Despite recent successes with biological agents as therapy for autoimmune inflammatory diseases such as rheumatoid arthritis (RA), many patients fail to respond adequately to these treatments, making a continued search for new therapies extremely important. Recently, the prevailing hypothesis that reactive oxygen species (ROS) promote inflammation was challenged when polymorphisms in Ncf1, that decrease oxidative burst, were shown to increase disease severity in mouse and rat arthritis models. Based on these findings we developed a new therapy for arthritis using oxidative burst-inducing substances.

T cell surface redox levels determine T cell reactivity and arthritis susceptibility.

Rats and mice with a lower capacity to produce reactive oxygen species (ROS) because of allelic polymorphisms in the Ncf1 gene (which encodes neutrophil cytosolic factor 1) are more susceptible to develop severe arthritis. These data suggest that ROS are involved in regulating the immune response. We now show that the lower capacity to produce ROS is associated with an increased number of reduced thiol groups (-SH) on T cell membrane surfaces.

Characterization of beta-hexosaminidase secretion in rabbit lacrimal gland.

The present study was aimed at validating the use of the lysosomal enzyme beta-hexosaminidase as a marker of secretory function in cultured rabbit lacrimal gland acinar cells. The secretory response and morphological characteristics of isolated acinar cells cultured in a serum-free medium supplemented with an extracellular matrix extract were monitored over time as part of optimization of our culturing protocol. Secreted beta-hexosaminidase activity was analyzed and compared with that of another lysosomal enzyme, cathepsin B, as well as protein secreted into the media, w or w/o the presence of secretagogues or protein kinase C activators and inhibitors.

Pristane, a non-antigenic adjuvant, induces MHC class II-restricted, arthritogenic T cells in the rat.

Pristane-induced arthritis (PIA) in rats, a model for rheumatoid arthritis (RA), is a T cell-dependent disease. However, pristane itself is a lipid and unable to form a stable complex with a MHC class II molecule. Therefore, the specificity and function of the T cells in PIA are as unclear as in rheumatoid arthritis.

Enhanced autoimmunity, arthritis, and encephalomyelitis in mice with a reduced oxidative burst due to a mutation in the Ncf1 gene.

The Ncf1 gene was recently identified as a strong regulator of severe arthritis in rat. This finding was surprising, because the disease-promoting allele mediated a lower level of reactive oxygen species in NADPH oxidase-expressing cells. We have now investigated a splice mutation of the Ncf1 gene in B10.

Differential gene expression in pristane-induced arthritis susceptible DA versus resistant E3 rats.

Arthritis susceptibility genes were sought by analysis of differential gene expression between pristane-induced arthritis (PIA)-susceptible DA rats and PIA-resistant E3 rats. Inguinal lymph nodes of naïve animals and animals 8 days after pristane injection were analyzed for differential gene expression. mRNA expression was investigated by microarray and real-time PCR, and protein expression was analyzed by flow cytometry or ELISA.

Two-loci interaction confirms arthritis-regulating quantitative trait locus on rat chromosome 6.

A form of genetic interaction, or epistasis, occurs when one gene interferes with the phenotypic effect of another nonallelic gene. In pristane-induced arthritis (PIA) in rats we have previously identified Pia3, on chromosome 6, to be a locus that regulates onset of disease. In a single congenic strain containing Pia3 on the arthritis-susceptible DA background, DA.

A comparative genetic analysis between collagen-induced arthritis and pristane-induced arthritis.

Objective: To compare the genetic regulation of collagen-induced arthritis (CIA) with that of pristane-induced arthritis (PIA) in rats.

Methods: A genome-wide linkage analysis of an (E3 x DA)DA backcross of rats with CIA (n = 364 male rats; the same strain combinations as previously used to determine the genetic control of PIA) was performed. The strongest loci in both CIA and PIA (i.

Identification and isolation of dominant susceptibility loci for pristane-induced arthritis.

Rheumatoid arthritis is a chronic inflammatory autoimmune disorder, controlled by multiple genes as well as environmental factors. With animal models, like the pristane-induced arthritis (PIA) in rats, it is possible to reduce the environmental effects and the genetic heterogeneity to identify chromosomal regions harboring genes responsible for the arthritis development. The PIA model has proved to be useful for identifying gene regions controlling different phases of the disease based on intercrosses between the resistant E3 and the susceptible DA rat.

Positional identification of Ncf1 as a gene that regulates arthritis severity in rats.

The identification of genes underlying quantitative-trait loci (QTL) for complex diseases, such as rheumatoid arthritis, is a challenging and difficult task for the human genome project. Through positional cloning of the Pia4 QTL in rats, we found that a naturally occurring polymorphism of Ncf1 (encoding neutrophil cytosolic factor 1, a component of the NADPH oxidase complex) regulates arthritis severity. The disease-related allele of Ncf1 has reduced oxidative burst response and promotes activation of arthritogenic T cells.

Both common and unique susceptibility genes in different rat strains with pristane-induced arthritis.

Pristane-induced arthritis (PIA) in rats is an animal model for rheumatoid arthritis (RA). We have previously identified seven quantitative trait loci (QTLs), which regulate arthritis development using a cross between the susceptible DA strain and the resistant E3 strain of rats (Pia2-8). In the present study the inbred rat strain LEW.