TY  - CHAP
M1  - Book, Section
TI  - Structure, Receptors, and Functions of Monocytes and Macrophages
A1  - Douglas, Steven D.
A1  - Douglas, Anne G.
A2  - Kaushansky, Kenneth
A2  - Prchal, Josef T.
A2  - Burns, Linda J.
A2  - Lichtman, Marshall A.
A2  - Levi, Marcel
A2  - Linch, David C.
Y1  - 2021
N1  - 
T2  - Williams Hematology, 10e
AB  - SUMMARYThe  monocyte  is  a  spherical  cell  with  prominent  surface  ruffles  and  blebs  when  examined  by  scanning  electron  microscopy.  As  the  monocyte  enters  the  tissue  and  differentiates  into  a  macrophage,  the  cell  volume  and  number  of  cytoplasmic  granules  increase.  Cell  shape  varies,  depending  on  the  tissue  in  which  the  macrophage  resides  (eg,  lymph  node,  lung,  liver  spleen,  brain).  A  characteristic  feature  of  macrophages  is  their  prominent  electron-dense  membrane-bound  lysosomes,  which  fuse  with  phagosomes  to  form  secondary  lysosomes.  The  latter  contain  ingested  cellular  and  noncellular  material  in  different  stages  of  degradation.  A  broad  range  of  surface  receptors  for  many  ligands,  including  the  Fc  portion  of  immunoglobulin,  complement  proteins,  cytokines,  chemokines,  lipoproteins,  and  others,  are  on  the  cell  surface.  Macrophages  play  a  major  role  in  innate  as  well  as  adaptive  immunity.  Macrophages  differ  in  appearance,  biochemistry,  and  function  based  on  the  environment  in  which  they  mature  from  embryonic  cells  or  circulating  monocytes.  These  differences  are  exemplified  by  the  diversity  among  dendritic  cells  of  lymph  nodes,  histiocytes  of  connective  tissue,  osteoclasts  of  bone,  Kupffer  cells  of  liver,  microglia  of  the  CNS,  and  macrophages  of  the  serosal  surfaces,  each  fashioned  to  meet  the  local  needs  of  the  mononuclear  phagocyte  system,  which  plays  a  role  in  inflammation  and  host  defense  against  microbes.  Modern  cell  biologic  methods  have  advanced  our  knowledge  of  the  surface  proteins  and  mechanisms  of  endocytosis  and  lysosomal  degradation  of  macrophages.  These  studies,  in  turn,  have  resulted  in  the  discovery  that  dendritic  cells  are  potent,  highly  specialized  antigen-presenting  cells.  Subsequent  development  of  monoclonal  antibodies  and  molecular  cloning  of  surface  proteins  and  cytokines,  followed  by  microarray  analysis  and  single  cell  omics,  provided  the  sensitive  and  specific  tools  which  enabled  the  analysis  of  monocyte/macrophage  functions  in  vitro  and  in  vivo,  bringing  important  insights  into  their  cytotoxic  and  antimicrobial  activities  and  their  tropic  and  homeostatic  functions.  
SN  - 
PB  - McGraw-Hill Education
CY  - New York, NY
Y2  - 2024/04/18
UR  - accessmedicine.mhmedical.com/content.aspx?aid=1180445349
ER  -