Skip to main content
. 2022 Jun 2;11(11):1824. doi: 10.3390/cells11111824

Table 2.

Commonly ascribed immune cell phenotypes.

Cell Type Phenotype Mechanism Characteristics
Platelets Immature platelets Emergency thrombopoiesis
  • -

    High granularity

  • -

    Increased size
Sepsis-induced splenic platelets IL-3-mediated splenic megakaryocyte maturation
  • -

    CD40Lhi
Lung-derived platelets S1P-gradient-dependent platelet shedding in pulmonary microvasculature
  • -

    Phenotypic distinction so far unclear [217]
Young vs. old Life-cycle dependent aging
  • -

    Desialylated old platelets

  • -

    Stimulation of TPO production
COATed platelets Dual stimulation with collagen and thrombin
  • -

    Phosphatidylserine exposure

  • -

    High fibrinogen binding
Post-emperipolesis platelets Megakaryocyte emperipolesis followed by thrombopoiesis
  • -

    Containing neutrophil membrane fragments
Plat 1 vs. Plat 2 Differing stimuli and microenvironments
  • -

    Pro-inflammatory vs. pro-resolution
Neutrophils NDN Density gradient purification
  • -

    Containing mostly mature neutrophils
LDN Density gradient purification
  • -

    Containing immature neutrophils

  • -

    Containing neutrophils with elevated CD66b, CD11b
N1 Increased following TGF-beta blockade
  • -

    Immunostimulating

  • -

    Cytotoxic, tumor-suppressive

  • -

    Mature phenotype

  • -

    Short lifecycle [218]

  • -

    CD11blo
N2 PPARy-dependent
  • -

    Immunosuppressive,

  • -

    Tumor-permitting, pro-metastatic

  • -

    CD206+

  • -

    Increasingly efferocytosed during stroke
Reverse-migrated neutrophils LTB4–Neutrophil Elastase-dependent
  • -

    Over-activated

  • -

    CD54hi CXCR1lo

  • -

    Capable of causing remote injury
Aged neutrophils Life-cycle-dependent aging, microbiota-TLR-MyD88-dependent
  • -

    CXCR4hi
Macrophages M1 LPS-, IFN-dependent
  • -

    Pro-inflammatory
M2 (a, b, c, d) IL-10, IL-4-dependent
  • -

    Anti-inflammatory
Alveolar Localization
  • -

    Patrolling of airways

  • -

    Diverse population (including SiglecF+ and SiglecF− cells)
Interstitial Localization
  • -

    Diverse population (including Lyve1+/−, MHCII+/−, CX3CR1+/− cells)

  • -

    Localized in interstitium
Resident Organ-inherent resident immune cells
  • -

    Not mobilized but detectable both under baseline and inflammatory conditions
Perivascular Localization vs. organ-specific expression patterns
  • -

    Diverse population [219]

  • -

    Capable of modulating vascular development
Profibrotic Increased in pulmonary bleomycin model
  • -

    SiglecF+ CD11c+ MHCIIhi
Monocyte derived Recruitment of monocytes and maturation to macrophages
  • -

    CX3CR1+ (mouse)-derived

  • -

    CD16/CD14 (human)-derived
Splenic macrophages Anatomic localization
  • -

    Marginal metallophilic macrophages

  • -

    Marginal zone macrophages

  • -

    Red pulp macrophages