RT Book, Section
A1 Lichtman, Marshall A.
A1 Kaushansky, Kenneth
A1 Prchal, Josef T.
A1 Levi, Marcel M.
A1 Burns, Linda J.
A1 Linch, David C.
SR Print(0)
ID 1189334014
T1 Monocytosis and Monocytopenia
T2 Williams Manual of Hematology, 10e
YR 2022
FD 2022
PB McGraw-Hill Education
PP New York, NY
SN 9781264269204
LK hemonc.mhmedical.com/content.aspx?aid=1189334014
RD 2024/04/25
AB Monocytes  in  the  blood  are  in  transit.  They  function  in  the  tissues,  where  they  mature  into  macrophages  and  participate  in:—  Inflammation,  including  granulomatous  reactions,  atheroma  formation,  and  tissue  repair—  Immunologic  reactions,  including  delayed  hypersensitivity—  Reactions  to  neoplasia  and  allograftsThe  need  for  macrophages  in  tissues  also  can  be  met  by  local  proliferation  of  macrophages,  not  requiring  increased  transit  of  blood  monocytes.In  normal  subjects,  a  mean  of  87%  of  blood  monocytes  intensely  express  CD14  (lipopolysaccharide  receptor)  but  not  CD16  (Fc  receptor)  (CD14++/CD16–),  the  classical  subset,  designated  MO1.A  mean  of  4%  of  blood  monocytes  have  weaker  expression  of  CD14  and  strongly  express  CD16  (CD14+CD16++),  the  intermediate  subset,  designated  MO2.A  third  monocyte  subset,  at  a  mean  of  9%  of  blood  monocytes,  have  weak  expression  of  CD14  and  strong  expression  of  CD16  (CD14low/CD16++),  the  nonclassical  subset,  designated  MO3.Distinctions  among  monocyte  subsets  have  been  validated  by  gene  expression  profiling.Older  persons  have  a  striking  decrease  in  the  proportion  of  classical  CD14++/CD16–  monocytes  to  intermediate  CD14+/CD16++  monocytes  compared  with  younger  persons.Disorders  rarely  produce  abnormalities  of  monocytes  alone  in  the  absence  of  other  blood  cell  abnormalities.