Intro to Haem Flashcards
What are the broad steps of Haemotopoiesis?
Pluripotent Haematopoietic stem cells
1) –> Uncommitted Stem Cells –> Myeloid Cells
2) –> Lymphocyte Stem Cells –> Lymphocytes
What are the myeloid cells?
- Erythrocytes
- Platelets
- Neutrophils
- Monocytes
- Basophils
- Eosinophils
Basically everything bar lymphocytes & NK cells
What are the lymphoid cells?
Lymphocytes (T & B Cells)
Nk cells
What hormone drives RBC production? where is it made?
Erythropoietin from kidneys
What hormone drives platelet production &where’s it made?
Thrombopoietin
In the liver
Lifespan of a platelet?
7 days
What drives neutrophil production?
Stimulated:
- Interleukins
- Colony Stimulating Factors (CSF)
Regulated by immune responses e.g. macrophages & IL-7
Lifespan of a neutrophil?
1-2days
What can we use to improve neutrophil number?
G-CSF
Good for neutropenia
What do eosinophils do?
Target parasites
They’re the main cells involved in allergy
How does the body identify different lymphocytes?
By surface antigen (aka CD markers)
What do the different lymphocytes do and where are they matured?
B cells make antibodies. Mature in marrow
T cells split into helper, cytotoxic & regulatory
Mature in Thymus
NK cells naturally kill
From what process in the development of T cells do lymphoma’s arise?
DNA recombination during production. This process ensures all lymphocytes are a little different
But it can go wrong leading to lymphoma
What is T cell +ve selection?
If gene rearrangement results in a functional receptor the cell is allowed to survive
What is T cell -ve selection?
Gene rearrangement leads to a self-recognising T cell which is then killed
How do our bodies identify self cells?
By HLA surface antigens
What are the types of HLA?
Class 1 - Displays own antigens on all nucleated cells
Class 2 - displays the antigens eaten by antigen-presenting cells
What’s the normal range for Haemoglobin, platelets &WBC & RBC ?
WBC 4-10 x10^9/L
Platelets 150-400 x10^9/L
RBC 4-5 x10^12/L
Haemoglobin 140-180 in men or 120-160g/L in women
What are the consequences of hypersplenism?
Pancytopenia- deficiency in all three components of blood
What are the consequences of hyposplenism?
Capsulated Bacteria Infection
Red Cell Changes
Which cells are classed as WBCs?
Neutrophils Basophils Eosinophils Lymphocytes Monocytes
What is the function of neutrophils and monocytes?
Ingest and destroy pathogens ( especially bacteria and fungi)
what are the most important diagnostic factors for haematology?
- FBC
- Clotting times
- Chemical assays: IRON, B12, FOLATE
- Marrow aspirate and trephine biopsy
- Lymph node biopsy
- Imaging
