ABSTRACT
StructuralAnalysesofRedBloodCellAutoantibodies389
phenotypesexceptRhnuiicellsthatlackallRhcomponents(28-31).Thispatternofreactivity hasledtothenotionofacommon"Rh-core"structuretowhichtheseantibodiesaredirected. However,whattheseserologicobservationsmeaninmoleculartermsisnotatallclear.For example,itispossiblethattheseautoantibodiesdonotbindtoRhantigenspersebuttoRh antigensincombinationwithsomeotherubiquitousRBCmembranecomponent(s)(32,33). Alternatively,theautoantigensmaynotbeRhrelatedatallbecauseRhnuncells,whichare misshapenandfragile(34)anddisplayavarietyofmembranetransportdefects(35),have decreasedexpressionofotherbloodgroupantigens,includingS,s,U,andN(36).Inasmall numberofcases,a"relativeRhspecificity"canbeobservedinwhichantiseraarepan-reactive butdisplayincreasedreactivityagainstcellspossessingcertainRhantigenssuchasRh(e).In stillfewercases,autoantibodiesspecificforparticularRhantigenshavebeendescribed(37,38). Inthesesituations,RBCslackingthecorrespondingRhantigenhavebeenfoundtosurvive betterinvivothanthosethatexpresstheantigen.
