SampleGelInformation:

Overview:

Osteonectinisanacidic,noncollagenousglycoprotein(Mr=29,000)originallyisolatedfromfetalandadultbovinebonematrix(1-5).InvitrobovineboneosteonectinbindstypeIcollagen,calcium(Kd=3x10-7M)andhydroxyapatite(Kd=8x10-8M)andhasbeenshowntobeapotentinhibitorofhydroxyapatiteseededcrystalgrowth(6).Inthiscontextithasbeensuggestedthatosteonectinmayplayanimportantroleintheregulationofbonemetabolismbybindinghydroxyapatitetocollagen.Recently,proteinshomologoustoosteonectinhavebeenidentifiedinanumberofcelltypes,mostofwhichareassociatedwithextracellularmatrixproduction(7).Theaminoacidsequence(fromCDNAsequences)ofoneoftheseproteins,humanplacentalSPARCisidenticaltohumanboneosteonectin.

Osteonectinhasalsobeenidentifiedasanalphagranulecomponentofhumanplateletsandissecretedduringactivation.Asmallportionofthesecretedosteonectinisexpressedontheplateletcellsurfaceinanactivationdependentmanner(8).Purifiedplateletosteonectinisasinglechainmoleculewhichexhibitsaslightlylargerapparentmolecularweightthanthatofosteonectinderivedfrombone(8).TheNH2-terminalsequencesofplateletandbone-derivedosteonectinareidentical,butthetwoproteinsdifferwithregardtotheextentotglycosylation(8-10).

HumanplateletosteonectinisisolatedfromthrombinactivatedplateletsasdescribedbyKelm,etal.(8).BovineboneosteonectinisisolatedfromdemineralizedbonebythemethodofRombergetal.(2).Bothproteinsaresuppliedin0.02MTris,0.15MNaCl,pH7.4,andshouldbestoredat-80oC.PurityisjudgedbySDS-PAGEanalysis.

Properties:

Haemtech生物制药服务（HBS）是一家领先的，符合cGMP要求的QC测试实验室，专门为生产重组和血浆衍生蛋白疗法的生物制药制造商提供分析服务，重点是那些会影响止血系统的药物。HBS使客户能够满足法规和质量测试要求，从而将其候选药物从开发转向商业化。

对生物制药的需求正在增长，并且该行业正在迅速采用外包策略，以作为满足不断升级的监管要求的一种方式。凭借在止血方面的丰富经验，HBS能够很好地协助开发影响凝血系统的药物产品。