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Background: Rheumatoid arthritis (RA) is a very complicated autoimmune disease with apparent synovial hyperplasia and cartilage and bone destruction. Aims: In the present study, we aimed to determine whether the pathogenesis of RA correlates with food allergy and which allergen(s) are relevant. Materials and Methods: We used type-II collagen (CII) to induce arthritis (collagen-induced arthritis, CIA) model in Wistar rats, and the development of arthritis was evaluated accordingly by scoring system. Proinflammatory cytokine levels in plasma were measured by enzyme-linked immunosorbent assay (ELISA), and concentrations of circulating immune complexes (CICs) were analyzed by C1q solid phase method. Furthermore, food-specific immunoglobulin G (IgG) and immunoglobulin E (IgE) levels were determined in the CIA model. Results: In the CIA model, we found that levels of tumor necrosis factor-alpha (TNF-a), interleukin (IL)-1, IL-6, and IL-17, as well as CICs, were elevated significantly. Moreover, concentrations of milk- or egg-specific IgG and IgE were enhanced strikingly in CIA rats. Conclusion: The results suggest that pathogenesis of RA correlates closely to increased egg- or milk-specific antibodies. [ABSTRACT FROM AUTHOR]

Rhesus (Rh) proteins share a conserved 12-transmembrane topology and specify a family of putative CO2 channels found in diverse species from microbes to human, but their functional essentiality and physiological importance in metazoans is unknown. To address this key issue and analyze Rh-engaged physiologic processes, we sought to explore model organisms with fewer Rh genes yet are tractable to genetic manipulations. In this article, we describe the identification in nematodes of two Rh homologues that are highly conserved and similar to human Rh glycoproteins, and we focus on their characterization in Caenorhabditis elegans. RNA analysis revealed that CeRh1 is abundantly expressed in all developmental stages, with highest levels in adults, whereas CeRh2 shows a differential and much lower expression pattern. In transient expression in human cells, both CeRh1 and CeRh2-GFP fusion proteins were routed to the plasma membrane. Transgenic analysis with GFP or LacZ-fusion reporters showed that CeRh1 is mainly expressed in hypodermal tissue, although it is also in other cell types. Mutagenesis analysis using deletion constructs mapped a minimal promoter region driving CeRh1 gene expression. Although CeRh2 was dispensable. RNA interference with CeRh1 caused a lethal phenotype mainly affecting late stages of C. elegans embryonic development, which could be rescued by the CbRh1 homologue from the worm Caenorhabditis briggsae. Taken together. our data provide direct evidence for the essentiality of the CeRh1 gene in C. elegans, establishing a useful animal model for investigating CO2 channel function by cross-species complementation. [ABSTRACT FROM AUTHOR]

In the present study, we characterized a sterile cpi-2a(ok1256) deletion mutant in Caenorhabditis elegans and showed that CPI-2a has an essential regulatory role during oogenesis and fertilization. We have also shown that the CPI2a inhibitor and both Ce-CPL-1 and Ce-CPZ-1 enzymes are present in the myo-epithelial sheath surrounding germ cells, oocytes, and embryos as well as in the yolk granules within normal oocytes. Staining of mutant worms with anti-yolk protein antibodies has indicted that the proteins are not present in the mature oocytes. Moreover, green fluorescent protein expression was absence or reduced in cpi-2a/yp170:gfp mutant oocytes, although it was expressed in one of the successfully developed embryos. Based on these results, we hypothesize that the sterility in cpi-2a(ok1256) mutant worms is potentially caused by two possible mechanisms: 1) defects in the uptake and/or processing of yolk proteins by the growing oocytes and 2) indirect induction of defects in cell-cell signaling that is critical for promoting germ line development, oocyte maturation, ovulation, and fertilization. A defect in any of these processes would have detrimental effects on the development of normal embryos and consequently normal production of progenies as we observed in cpi-2a mutant worms. This is the first study that demonstrates the expression of cysteine proteases and their endogenous inhibitor in the gonadal sheath cells surrounding germ cells and oocytes, which indirectly have established their potential involvement in proteolytic processing of molecules within the gonadal sheath cells, such as components of the extracellular matrix or the cytoskeletal proteins, which are essential for proper cell-cell signaling activities of the gonadal sheath cells during normal maturation and ovulation processes. [ABSTRACT FROM AUTHOR]