This document discusses leukopoiesis and its regulation with clinical importance. It begins by defining white blood cells and providing their general features. It then describes the classification, lifespan, and functions of different types of WBCs. It explains the process of leukopoiesis and the stages involved. Growth factors like cytokines and colony stimulating factors that regulate leukopoiesis are identified. Finally, the clinical importance is discussed through conditions like infectious mononucleosis, myeloid leukemoid reaction, myeloid neoplasms including myeloproliferative neoplasms, acute myeloid leukemia, and myelodysplastic syndromes. Their WHO classifications and clinical manifestations are outlined.

1. WBC
TOPIC:LEUKOPOIESIS & ITS
REGULATION WITH CLINICAL
IMPORTANCE
Presented by-
Sayandip majumdar
Samat mallick
Sukanya pathak
Md Ashik billa baidya

2. WBC:INTRODUCTION
 In 1843 Gabriel Andral & William
Addison,reported the first description of
leucocytes.
 White blood cells (WBCs) or leukocytes
are the colorless and nucleated formed
elements of blood (leukos = white).
 WBC is made in the bone marrow and
found in the blood and lymph tissue.

3. General features of WBC:
 Color- Colorless
 Number- less 4000-11000/cu mm
• Size- maximum diameter of 18 micron
• Shape- Irregular
• Hb- Absent
• Nucleus- present
• Types- many
 Lifespan- Shorter ½ to 15 days
 Function – Defence & immunity

4. CLASSIFICATION OF WBC:

5. LIFESPAN & FUNCTIONS OF WBC:

6. LEUKOPOIESIS:
 The process of development and
maturation of leukocytes(WBC), is called
leukopoiesis.

7. Cont.
STEM CELLS:
 Stem cells are the primary cells capable of
self-renewal and differentiating into
specialised cells.
 Committed pluripotent stem cell gives rise
to leukocytes through various stages.

8. STEM CELLS

9. STAGES OF LEUKOPOIESIS:

10. GROWTH FACTORS NECESSARY FOR LEUKOPOIESIS:
Leukopoiesis is influenced by-
haemopoietic growth factors.
colony stimulating factors.
Cont.

11. Haemopoietic growth factors
 Hematopoietic growth factors or growth inducers
are the interleukins and stem cell factors . these
factors induced the proliferation of PHSCs.
Interleukins (IL) are glycoproteins, which
belongs to the cytokines family.
 T cells > IL-3
 T cells,endothelial cells & macrophages > IL-6
 Osteoblast > IL-11
Cont.

12. Colony stimulating factors
 Colony-stimulating factors(CSFs) are
proteins which promote the formation of
colony forming blastocystes.
 TYPES:
 Monocytes & endothelial cells > Granulocyte-
CSF(G-CSF)
 Monocytes, endothelial cells and t lymphocytes >
granulocyte monocyte CSF (GM-CSF)
 Monocytes & endothelial cells> Monocyte-CSF(M-
CSF)
Cont.

13. SCF= Stem cell factor; Tpo= Thrombopoietin; IL= Interleukin; GM-CSF= Granulocyte Macrophage-
colony stimulating factor; Epo= Erythropoietin; M-CSF= Macrophage-colony stimulating factor; G-
CSF= Granulocyte-colony stimulating factor; SDF-1= Stromal cell-derived factor-1; FLT-3 ligand= FMS-
like tyrosine kinase 3 ligand; TNF-a = Tumour necrosis factor-alpha; TGFβ = Transforming growth
factor beta

14. CLINICAL IMPORTANCE

15. INFECTIOUS MONONUCLEOSIS
 Epstein-Barr virus (EBV) is the most common cause of
infectious mononucleosis, but other viruses can also cause this
disease. It is common among teenagers and young adults
CLINICAL FEATURES:
 Fatigue.
 Sore throat
 Hepatitis
 lymphadenopathy
 Swollen tonsils.
 Encephalitis
 Meningitis
 Pneumonitis
 Skin rash

16. MYELOID LEUKAEMOID REACTION:
1.Infections e.g. staphylococcal pneumonia, disseminated
tuberculosis, meningitis, diphtheria, sepsis,
endocarditis,plague, infected abortions etc.
2. Intoxication e.g. eclampsia, mercury poisoning, severe
burns.
3. Malignant diseases e.g. multiple myeloma,
myelofibrosis,Hodgkin’s disease, bone metastases.
4. Severe haemorrhage and severe haemolysis.

17. MYELOID NEOPLASMS:
 MYELOPROLIFERATIVE NEOPLASMS(MPN)
 This is a group of neoplastic proliferation of
multipotent haematopoietic stem cells.
 Besides their common stem cell origin, these
disorders are closely related, occasionally leading
to evolution of one entity into another during the
course of the disease.

18. WHO CLSSIFICATION OF
MYELOPROLIFERATIVE NEOPLASMS(MPN):
 The WHO classification of myeloproliferative disorders
includes 9 types.(a/c WHO 2016 Classifi.)
 1.Chronic myeloid leukemia (CML)
 2.Chronic neutrophilic leukemia (CNL)
 3.Polycythemia vera (PV)
 4.Primary myelofibrosis (PMF)
 5.prefibrotic/early stage PMF
 6.overt fibrotic stage Essential thrombocythemia (ET)
 7.Chronic eosinophilic leukemia,not otherwise
specified(NOS)
 8.Mastocytosis
 9.MPN, unclassifiable

19. ACUTE MYELOID LEUKAEMIA(AML):
 WHO CLASSIFICATION Recent WHO
classification for AML
 differs from revised FAB classification in the
following ways:
 1. AML with recurrent genetic abnormalities.
 2.AML with myelodysplasia related changes.
 3. Therapy related AML.
 4. AML, not otherwise categorised.
 5. Myeloid sarcoma.
 6. Myeloid proliferations related to Down’s
syndrome.
 7. Blastic plasmacytoid dentritic cell neoplasm.

20. Clinical manifestations of AML:
 Clinical manifestations of AML are divided
into 2 groups:
1.those due to bone marrow failure:Anaemia,
Bleeding manifestations, Infections of mouth,throat, skin,
respiratory, perianal and other sites.
2.those due to organ infiltration:Pain and
tenderness of bones, Lymphadenopathy, Splenomegaly,
Hepatomegaly , Gum hypertrophy, Chloroma or
granulocytic sarcoma etc.

21. MYELODYSPLASTIC SYNDROMES(MDS):
 Myelodysplastic syndromes (MDS) are a
heterogeneous group of haematopoietic clonal
stem cell disorders having abnormal
development of different marrow elements (i.e.
dysmyelopoiesis),
 cytopenias,cellular marrow and ineffective blood
cell formation.
 These conditions are, therefore, also
termed as preleukaemic syndromes or
dysmyelopoietic syndromes.

22. WHO CLASSIFICATION OF MDS(2016
revised)
 1.MDS with single lineage dysplasia(MDS-SLD)
 2.MDS with multilineage dysplasia(MDS-MLD)
 3.MDS with ring sideroblasts (MDS-RS)
 4.MDS with excess blasts(MDS-EB)
 5.MDS with isolated del(5q)
 6.MDS, unclassifiable
 7.Refractory cytopenia of childhood.
 8.Myeloid neoplasms with germ line
predisposition.

23. CLINICAL FEATURES OF MDS:
1. Anaemia appreciated by pallor, fatigue
and weakness.
2. Fever.
3. Weight loss.
4. Sweet syndrome (having neutrophilic
dermatosis seen in some cases).
5. Splenomegaly (een in 20% cases of
MDS).

24. Thank you.