Search results for "Type II collagen"

Human nasoseptal chondrocytes maintain their differentiated phenotype on PLLA scaffolds produced by thermally induced phase separation and supplement…

2018

Damage of hyaline cartilage such as nasoseptal cartilage requires proper reconstruction, which remains challenging due to its low intrinsic repair capacity. Implantation of autologous chondrocytes in combination with a biomimetic biomaterial represents a promising strategy to support cartilage repair. Despite so far mostly tested for bone tissue engineering, bioactive glass (BG) could exert stimulatory effects on chondrogenesis. The aim of this work was to produce and characterize composite porous poly(L-lactide) (PLLA)/1393BG scaffolds via thermally induced phase separation (TIPS) technique and assess their effects on chondrogenesis of nasoseptal chondrocytes. The PLLA scaffolds without or…

Evidence for auto-reactivity against the collectins, SP-A and MBL, in rheumatoid arthritis synovial fluids: Lack of cross-reactivity with C1q or type…

1997

Alginate-Agarose Hydrogels Improve the In Vitro Differentiation of Human Dental Pulp Stem Cells in Chondrocytes. A Histological Study

2021

[EN] Matrix-assisted autologous chondrocyte implantation (MACI) has shown promising results for cartilage repair, combining cultured chondrocytes and hydrogels, including alginate. The ability of chondrocytes for MACI is limited by different factors including donor site morbidity, dedifferentiation, limited lifespan or poor proliferation in vitro. Mesenchymal stem cells could represent an alternative for cartilage regeneration. In this study, we propose a MACI scaffold consisting of a mixed alginate-agarose hydrogel in combination with human dental pulp stem cells (hDPSCs), suitable for cartilage regeneration. Scaffolds were characterized according to their rheological properties, and their…

Highly porous novel chondro-instructive bioactive glass scaffolds tailored for cartilage tissue engineering

2021

Abstract Cartilage injuries remain challenging since the regenerative capacity of cartilage is extremely low. The aim was to design a novel type of bioactive glass (BG) scaffold with suitable topology that allows the formation of cartilage-specific extracellular matrix (ECM) after colonization with chondrogenic cells for cartilage repair. Highly porous scaffolds with interconnecting pores consisting of 100 % BG were manufactured using a melting, milling, sintering and leaching technique. Scaffolds were colonized with porcine articular chondrocytes (pAC) and undifferentiated human mesenchymal stromal cells (hMSC) for up to 35 days. Scaffolds displayed high cytocompatibility with no major pH …

Enzymatic alteration of C1q, the collagen-like subcomponent of the first component of complement, leads to cross-reactivity with type II collagen

1988

AbstractNative serum C1q, the collagenous-like subcomponent of the first component of complement, is not recognized by polyclonal anti-collagen type II antibodies. However, when purified C1q was subjected to limited proteolysis by collagenase it showed antigenic cross-reactivity with collagen type II. The same cross-reactivity was observed with hemolytically active C1q in synovial fluids of patients with rheumatoid arthritis (RA), whereas C1q from synovial fluids of patients with osteoarthritis (OA), villo-nodular synovitis and ankylosing spondylitis was not recognized by this antibody. However, incubation of synovial fluid C1q of OA patients with synovial fluid leucocytes from RA patients …

In-vitro Proteoglykansynthese in redifferenzierten Chondrozyten

1989

Human chondrocytes growing in monolayer cultures de-differentiate and produce type I collagen. They re-differentiate and resume their in-vivo characteristics (including the production of type II collagen) when cultured in an agarose-gel. To characterize the modulated cells in more detail, biochemical studies were performed in chondrocytes suspended in agarose for 1 to 3 weeks.

In vitro 30 nm silver nanoparticles promote chondrogenesis of human mesenchymal stem cells

2015

Silver nanoparticles (Ag NPs) are one of the most widely used products in nano-medicine due to their broad-spectrum antimicrobial activity. In tissue engineering, Ag NPs are often incorporated as antibacterial agents in scaffolds, which are subsequently loaded with human bone marrow-derived mesenchymal stem cells (hMSCs). In this study, we investigated the effect of Ag NPs on chondrogenesis of hMSCs. The synthesized Ag NPs were spherical in shape, with a mean diameter of ∼30 nm. After 24 h exposure, Ag NPs were taken up into hMSCs and mainly distributed in the cytoplasm, the nucleus and different sized vesicles. We examined the chondrogenesis through several methods, including glycosaminogl…

Distinct Recognition of Collagen Subtypes by α1β1 and α2β1Integrins

2000

Two integrin-type collagen receptors, α1β1 and α2β1, are structurally very similar. However, cells can concomitantly express the both receptors and they might have independent functions. Here, Chinese hamster ovary (CHO) cells, which lack endogenous collagen receptors, were transfected with either α1 or α2 integrin cDNA. Cells were allowed to adhere to various collagen types and their integrin function was tested by observing the progression of cell spreading. The cells expressing α1β1 integrin could spread on collagen types I, III, IV, and V but not on type II, while α2β1 integrin could mediate cell spreading on collagen types I-V. Type XIII is a transmembrane collagen and its interaction …

Altered (oxidized) C1q induces a rheumatoid arthritis-like destructive and chronic inflammation in joint structures in arthritis-susceptible rats.

1997

Previous studies have identified an altered C1q molecule in synovial fluids from the joints of rheumatoid arthritis patients. We therefore immunized arthritis-susceptible Lewis 1A.AVN rats with either native C1q (C1q nat), altered (oxidized) C1q (C1q ox), or type II collagen (CII, induces arthritis in these animals), in order to induce arthritis. Unlike C1q nat, both CII and C1q ox were able to induce swelling and erythema of joints consistent with an arthritis-like inflammatory reaction. Histopathological evaluation of individual joint sections revealed synovitis, bursitis and tendovaginitis, massive joint destruction, and severe pannus formation. In a time-course study, no differences in …

Poly(γ-Glutamic Acid) as an Exogenous Promoter of Chondrogenic Differentiation of Human Mesenchymal Stem/Stromal Cells

2015

Cartilage damage and/or aging effects can cause constant pain, which limits the patient's quality of life. Although different strategies have been proposed to enhance the limited regenerative capacity of cartilage tissue, the full production of native and functional cartilaginous extracellular matrix (ECM) has not yet been achieved. Poly(γ-glutamic acid) (γ-PGA), a naturally occurring polyamino acid, biodegradable into glutamate residues, has been explored for tissue regeneration. In this work, γ-PGA's ability to support the production of cartilaginous ECM by human bone marrow mesenchymal stem/stromal cells (MSCs) and nasal chondrocytes (NCs) was investigated. MSC and NC pellets were cultur…