Mucification of the cumulus layer around the oocyte is an obligatory process for female fertility. Tumor necrosis factor-induced protein-6 (TNFIP6 or TSG6) has been shown to be specifically expressed during this process. We have generated TNFIP6-deficient mice and tested the ability of their cumulus cells to undergo mucification. Cumulus cell-oocyte complexes fail to expand in TNFIP6-deficient female mice because of the inability of the cumulus cells to assemble their hyaluronan-rich extracellular matrix. The impaired cumulus matrix formation is due to the lack of covalent complexes between hyaluronan and the heavy chains of the inter-α-trypsin inhibitor family. As a consequence, TNFIP6-deficient females are sterile. Cultured TNFIP6-deficient cumulus cell-oocyte complexes also fail to expand when stimulated with dibutyryl cyclic AMP or epidermal growth factor. Recombinant TNFIP6 is able to catalyze the covalent transfer of heavy chains to hyaluronan in a cell-free system, restore the expansion of Tnfip6-null cumulus cell-oocyte complexes in vitro, and rescue the fertility in Tnfip6-null females. These results provide clear evidence that TNFIP6 is a key catalyst in the formation of the cumulus extracellular matrix and indispensable for female fertility.

Objective. To apply and analyze the mechanisms of action of dimethyldioctadecylammonium bromide (DDA), a powerful adjuvant that does not have the side effects of the conventionally used Freund's adjuvants, in proteoglycan-induced arthritis (PGIA) and collageninduced arthritis (CIA).Methods. PGIA and CIA were generated using standard immunization protocols with cartilage proteoglycan aggrecan (PG) or human type II collagen (CII) emulsified with Freund's complete adjuvant (CFA), and compared with PGIA and CIA generated using immunization protocols in which the same antigens were used in combination with the adjuvant DDA. Immune responses to immunizing and self PGs and CII, and the incidence, severity, and onset of arthritis were monitored throughout the experiments. In addition, a new, inexpensive, and powerful method of inducing arthritis using crude cartilage extracts is described.Results. A significantly reduced onset period and a more severe arthritis were achieved in BALB/c mice immunized with cartilage PGs in DDA. PGs from bovine, ovine, and porcine cartilage, which otherwise have no effect or have only a subarthritogenic effect, and crude extracts of human osteoarthritic cartilage induced a 100% incidence with a very high arthritis score in BALB/c mice. The overall immune responses to either CII or PG were similar in antigen/CFA-immunized and antigen/DDA-immunized animals, but the Th1/Th2 balance shifted significantly toward a Th1 bias in DDAinjected animals with either PGIA or CIA.Conclusion. DDA, which was first used in autoimmune models, is a potent nonirritant adjuvant, which eliminates all undesired side effects of the Freund's adjuvants. DDA exerts a strong stimulatory effect via the activation of nonspecific (innate) immunity and forces the immune regulation toward Th1 dominance. These lines of evidence also suggest the possibility that seemingly innocuous compounds may exert an adjuvant effect in humans and may create the pathophysiologic basis of autoimmunity in susceptible individuals via the activation/stimulation of innate immunity.Several lines of evidence indicate that the effector mechanism that initially attacks the small joints in rheumatoid arthritis (RA) is T cell driven. As a result, an aggressive synovial pannus develops that destroys articular cartilage and bone, leading to massive ankylosis and deformities of the peripheral joints. The disease has a progressive character, with involvement of more and more joints over time. While the primary target organ is the synovial joint, there is no clear evidence that any macromolecule of cartilaginous tissues, bone, or synovium would be a preferential autoantigen. Nevertheless, the most relevant animal models of RA appear to be those induced by cartilage matrix components, such as type II collagen (CII) or proteoglycan aggrecan (PG).Systemic immunization of genetically susceptible rodents with cartilage-specific CII (1,2) or of BALB/c or

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Cardiovascular disease is a leading cause of mortality in rheumatoid arthritis (RA). Endothelial dysfunction often precedes manifest atherosclerosis. Both traditional, Framingham risk factors and inflammation-associated factors are involved in RA-associated atherosclerosis. Among imaging techniques, the early determination of common carotid intima-media thickness (ccIMT), flow-mediated vasodilation (FMD), and nitroglycerine-mediated vasodilation (NMD) may be useful to determine atherosclerosis and endothelial dysfunction. We and others found increased ccIMT and impaired FMD in RA patients. Among immunological and metabolic laboratory markers, anticyclic citrullinated peptide (anti-CCP) antibodies, IgM rheumatoid factor, circulating immune complexes, pro-inflammatory cytokines including tumor necrosis factor-alpha (TNF-alpha) and interleukin-6 (IL-6), Th0/Th1 T cells, homocysteine, dyslipidemia, decreased folate and vitamin B12 production, and impaired paraoxonase activity may all be involved in the development of vascular disease in RA. The early diagnosis of endothelial dysfunction and atherosclerosis, active immunosuppressive treatment, the use of drugs that control atherosclerosis, changes in sedentary lifestyle, and the close follow-up of RA patients may help to minimize cardiovascular risk in these individuals.