SampleGelInformation:

Overview:

β-thromboglobulin(b-TG),isalowmolecularweight,heparin-binding,platelet-derivedprotein(1).Itissimilartoplateletfactor-4(PF-4)inthatitislocalizedwithintheplateletalpha-granuleatlevelsreportedtorangefrom8.1-24.2µgper109platelets(2,3).Therelativeconcentrationofβ-TGinplateletsexceedsthatofplasmaby260,000-fold(4)makingβ-TGaconvenientMarkerofplateletactivation.Structurally,β-TGisanalogoustoPF-4inthat,initsnativestate,β-TGisatetramer(1)consistingoffouridentical8800molecularweightpeptidechains(5).IncontrasttoPF-4,β-TGexhibitsaloweraffinityforheparinandalsoexistsasalargermolecularweightspeciesknownas"lowaffinityPF-4"(LAPF-4)(2).β-TGisderivedfromtheproteolyticremovaloffourNH2-terminalaminoacidresiduesfromaLAPF-4(6,7).Immunologicalscreeningofpartiallyfractionatedsupernatantfromactivatedplateletsrevealedahighlybasicformofβ-TGdistinctfromLAPF-4(7).Thisbasicβ-TGspecies,termedplateletbasicprotein(PBP),wassubsequentlyisolated(8)andlaterconcludedfromimmunological,peptidesequencing,andproteolyticprocessingstudiestobeahighermolecularweightprecursorformofbothLAPF-4andβ-TG(9,10).

Thephysiologicalfunctionofβ-TGisnotknown.Whileearlystudiessuggestedthattheprecursorformsofβ-TGweremitogenicformousefibroblasts(8,11),itwaslaterconcludedthatthisactivitywasduetogrowthfactorcontamination(10).β-TGhasalsobeenreportedtoinhibitprostacyclin-I2productionbyendothelialcells(12),however,therelevanceofthiseffecthasbeencalledintoquestion(13,14).Thechemotacticactivityofplateletalpha-granuleproteinsforhumanfibroblastshasbeenattributedtobothPF-4andβ-TG(15).

Humanβ-TGispreparedfromthesupernatantofactivatedplateletsbyheparin-agaroseaffinitychromatographyandgelfiltration(1,2).Thepurifiedproteinissuppliedin25mMHepes,150mMNaClpH7.4andshouldbestoredat-80°C.PurityisassessedbySDS-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。