Cardiac myocyte cell surface: Identification and expression of differentiation antigens during chick heart development☆

[摘要] Cardiacmyocytesfromvariousstagesofchickdevelopmentwereexaminedforspecificcell-surfaceantigensnotfoundonskeletalmuscletodetermineifspecificationofthisstriatedmuscle'scell-surfaceantigenicityaccompaniesdifferentiationofcardiactissue.Rabbitantiseraraisedagainst10-daychickembryoniccardiaccellswereassayedforspecificanti-cell-surfaceantibodieswiththecomplement-dependent51Crreleaseandindirectimmunofluorescenceassays.Identificationofspecificsurfaceantigenswaspossiblefollowingremovalofcross-reactiveantibodiesbyabsorptionofa125dilutionofanti-cardiacserumwithskeletalmusclecells;asignificanttiterremainedforcardiaccultures,whiletheabsorbedantiserumnolongerlysedskeletalmusclecells.Asecondclassofsharedsurfaceantigenscommontobothheartandskeletalmusclecellswasdetectableathigherdilutions(1250).Thesesharedantigenswereexpressedinquantitativelysimilaramountsofbothcellsurfaces,althoughonelotofantiseraappearedtodetectaparticularsharedantigenthatwasslightlyenrichedoncardiaccells.Indirectimmunofluorescencefurthercorroboratedthespecificityfoundwiththe51Crreleaseassay;fluorescentstainingspecificforcardiaccellsurfacesremainedafterremovalofalldetectablefluorescenceonskeletalmusclecells.Preferentiallysisofcardiacmyocytesbutnotcardiacfibroblastsbytheabsorbedantiserumdemonstratedthatthecardiacmyocyteexpressesauniqueantigeniccompositionspecificforitsdifferentiatedstate.Titrationoftheabsorbedantiserumagainstvariousdevelopmentalagesindicatesthatthesespecificantigensareexpressed,andataconstantlevel,fromDay4toDay15ofchickembryogenesis.Last,cytolytictestsagainstapanelofembryoniccelltypesindicatesthattheabsorbedantiserumisnotabsolutelytissuespecific,butcross-reactstoalimitedextentwithkidneyandsomeendodermalorgans.Nonetheless,thestrongestreactivityremainsforcardiaccells,thetissueagainstwhichtheantiserumwasraised.

[学科分类] 生物科学（综合）