title: Beta-1 integrin expression by human nasal chondrocytes in microcarrier spinner culture.
abstract: Beta-1 integrin plays a major role in cell attachment and is believed to be involved in mediating the interactions of chondrocytes with their environment. We previously reported that articular chondrocytes propagated in microcarrier spinner culture proliferated and reexpressed their chondrocytic protein. The goal of the present study was to investigate the expression of beta-1 integrin by chondrocytes growing on the surface of microcarriers. Nasal chondrocytes (4 x 10(3)/cm(2)) were seeded on microcarriers and incubated at 37 degrees C, 5% CO(2), 60 rpm. Expression of chondrocyte markers and beta-1 integrin was determined using reverse transcriptase-polymerase chain reaction and immunocytochemical analyses. De novo synthesis of sulfate-containing proteoglycans was studied using 35SO(4) incorporation techniques. Like articular chondrocytes propagated in microcarrier spinner culture, nasal chondrocytes expressed high levels of collagen type II mRNA, whereas collagen type I mRNA levels were low. Aggrecan mRNA was detectable and levels of de novo 35SO(4) incorporation were high. Chondrocytes immunostained intensely for collagen type II and keratan sulfate but did not stain for collagen type I. beta-1 integrin mRNA levels were high, and the protein was immunolocalized to regions of cell-to-cell or cell-to-microcarrier contact. The fact the chondrocytes expressed high levels of beta-1 integrin raises the possibility that this integrin molecule has a role in the maintenance of the chondrocytic phenotype.
authors.affiliation: Johns Hopkins University, Department of Orthopaedic Surgery, Division of Arthritis Surgery, Good Samaritan Hospital, Professional Office Building, G-1, 5601 Loch Raven Boulevard, Baltimore, Maryland 21239, USA.
authors.forename: B Y
authors.initials: BY
authors.lastname: Bouchet
authors.forename: M
authors.initials: M
authors.lastname: Colón
authors.forename: A
authors.initials: A
authors.lastname: Polotsky
authors.forename: A H
authors.initials: AH
authors.lastname: Shikani
authors.forename: D S
authors.initials: DS
authors.lastname: Hungerford
authors.forename: C G
authors.initials: CG
authors.lastname: Frondoza
mesh_terms: D053674:Aggrecans; D015415:Biomarkers; D018929:Cell Culture Techniques / Q000295:instrumentation* / Q000379:methods; D019902:Chondrocytes / Q000378:metabolism*; D003094:Collagen / Q000096:biosynthesis / Q000235:genetics; D016326:Extracellular Matrix Proteins; D020869:Gene Expression Profiling; D006801:Humans; D007124:Immunoenzyme Techniques; D019012:Integrin beta1 / Q000096:biosynthesis* / Q000235:genetics; D007632:Keratan Sulfate / Q000096:biosynthesis / Q000235:genetics; D037181:Lectins, C-Type; D008297:Male; D008863:Microspheres; D008875:Middle Aged; D009300:Nasal Septum / Q000166:cytology*; D020033:Protein Isoforms / Q000096:biosynthesis / Q000235:genetics; D011509:Proteoglycans / Q000096:biosynthesis / Q000235:genetics; D012333:RNA, Messenger / Q000096:biosynthesis; D020133:Reverse Transcriptase Polymerase Chain Reaction
chemical_list: D053674:Aggrecans; D015415:Biomarkers; D016326:Extracellular Matrix Proteins; D019012:Integrin beta1; D037181:Lectins, C-Type; D020033:Protein Isoforms; D011509:Proteoglycans; D012333:RNA, Messenger; D003094:Collagen; D007632:Keratan Sulfate