Updated: 2/13/2018

Blood Cell Differentiation

Topic
Review Topic
0
0
Videos
2
Overview
 

This illustration highlights the basic development of various blood cells from hematopoietic stem cells.

 
Introduction
 
Blood Cell Types
Type Description
Erythrocyte
  • Red cell responsible for carrying O2 to tissues, and CO2 to lungs
  • Erythropoietin increases RBC production
  • Glucose uptake not affected by insulin
  • Life span of 120 days
  • Most energy produced is via glycolysis
  • Hexose monophosphate (HMP) shunt to produce NAPDH and ribose 5-phosphate
Platelets
  • Derived from megakaryocytes
  • Plays a role in hemostasis
  • Endothelial damage leads to platelet aggregation via other platelets and fibrinogen
  • Contains granules that are secreted upon platelet activation
    • dense granules – ADP, Ca2+
    • α-granules – vWF, fibrinogen, platelet-derived growth factor (PDGF)
Mast cells
  • Involved in allergic reaction via a type I hypersensitivity mechanism
  • Granules containing substances such as histamine and heparin
  • Receptors (FcεR1) on mast cell can bind to IgE
    • IgE binding → cross-linking → degranulation
Monocytes
  • When in tissues, it differentiates into macrophages
Macrophages
  • Has ability to ingest pathogens, cellular debris, and dead or dying cells
  • Interferon-γ is an important activator of macrophages
  • Antigen presenting abilities via MHC II
  • Involved in granuloma formation (i.e., tuberculosis)
Dendritic cell
  • Antigen presenting cell via MHC II
  • Acting as a link between the innate and adaptive immune system
White blood cell differential
  • Neutrophils (54 – 62%)
    • if ↑, think bacterial infection
    • ↑ myeloid proliferation due to conditions such as bacterial infections would ↑ band cells
      • Band cell = immature neutrophils
    • C5a, IL-8, LTB4 are some molecules that promote chemotaxis in neutrophils to infection or inflammation sites
    • hypersegmented in vitamin B12 or folate deficiency
  • Lymphocytes (25 – 33%)
    • B-cell
      • matures in marrow
      • differentiates into antibody producing cells (plasma cells) when encountering antigen
      • antigen presenting ability via MHC II
    • T-cell
      • matures in thymus
      • cytotoxic T-cell: CD8+ recognize MHC I
      • helpter T-cell: CD4+ recognize MHC II
      • T-cells are activated with CD28 costimulation
  • Monocytes (3 – 7%)
  • Eosinophils (1 – 3%)
    • ↑ in conditions such as helminthic infection, neoplasia, Addison disease, and so forth
  • Basophils (0 – 0.75%)
    • involved in allergic reactions
    • granules contain heparin and histamine
    • can be ↑ in chronic myelogenous leukemia (CML)
      • can be helpful in differentiating from leukemoid reaction
 

Please rate topic.

Average 3.5 of 23 Ratings

Thank you for rating! Please vote below and help us build the most advanced adaptive learning platform in medicine

The complexity of this topic is appropriate for?
How important is this topic for board examinations?
How important is this topic for clinical practice?
VIDEOS (2)
Topic COMMENTS (6)
Private Note