Pivotal Advance: Peritoneal cavity B‐1 B cells have phagocytic and microbicidal capacities and present phagocytosed antigen to CD4+ T cells

Journal of Leukocyte Biology: An Official Publication of the Reticuloendothelial Society

关键词: mouse;    phagocytosis;    antigen presentation;    evolution;    particulate;   

DOI  :  10.1189/jlb.0711372

学科分类：生理学

来源: Federation of American Societies for Experimental Biology

【 摘 要 】

Breakingthelong‐heldparadigmthatprimaryBcellsarenotphagocytic,severalstudieshavedemonstratedrecentlythatBcellsfromfish,amphibians,andreptilianshaveasignificantphagocyticcapacity.WhethersuchcapacityhasremainedconservedincertainmammalianBcellsubsetsispresentlyanenigma.Here,wereportapreviouslyunrecognizedabilityofPerCB‐1aandB‐1blymphocytestophagocytoselatexbeadsandbacteria.Incontrast,B‐2lymphocyteshadanalmostnegligibleabilitytointernalizetheseparticles.Uponphagocytosis,B‐1aandB‐1bcellswereabletomaturetheirphagosomesintophagolysosomesanddisplayedtheabilitytokillinternalizedbacteria.Importantly,B‐1aandB‐1bcellseffectivelypresentantigenrecoveredfromphagocytosedparticlestoCD4+Tcells.However,thesecellsshowedamuchlowercompetencetopresentsolubleantigenorantigenfromlarge,noninternalizedparticles.B‐1BcellspresentedparticulateandsolubleantigentoCD4+Tcellsmoreefficientlythanmacrophages,whereasDCswerethemostpotentAPCs.ThenovelphagocyticandmicrobicidalabilitiesidentifiedinB‐1Blymphocytesstrengthentheinnatenaturethathaslongbeenattributedtothesecells.Inthecontextofadaptiveimmunity,weshowthattheseinnateimmuneprocessesarerelevant,astheyenableB‐1Bcellstopresentphagocytosableparticulateantigen.Thesecapacitiespositionthesecellsatthecrossroadsthatlinkinnatewithadaptiveimmuneprocesses.Inabroadercontext,thesenewlyidentifiedcapacitiesofB‐1Bcellsfurthersupportthepreviouslyrecognizedfunctional,developmental,andevolutionaryrelationshipsbetweenthesecellsandmacrophages...

【 授权许可】

CC BY