white blood cells Flashcards
- What is the precursor to macrophages?
- Give 3 examples of granulocytes
- What do the granules in granulocytes contain?
Monocytes
Basophil, Neutrophil and Eosinophil Agents for killing phagocytic material
- Where does cell division of granulocytes occur?
- What is the main function of neutrophils?
- How long do neutrophils survive in circulation before they migrate to tissues?
In myeloblasts, promyelocytes and myelocytes
Defence against infection by phagocytosing and then killing organisms Chemotaxis 7-10 hours
- What is the main function of neutrophils?
- How long do neutrophils survive in circulation before they migrate to tissues?
- Explain how neutrophils migrate to areas of inflammation
Defence against infection by phagocytosing and then killing organisms
Chemotaxis
7-10 hours Chemotaxis - Neutrophils become marginated in the vessel lumen, adhere to the endothelium and migrate into tissues
- What is the precursor to eosinophils?
- What is the main function of eosinophils?
Myeloblast
Defence against parasitic infection
regulate hypersensitivity reactions
- What do the granules in basophils contain?
- What are the functions of basophils?
Stores of histamine, heparin and proteolytic enzymes
Variety of immune and inflammatory responses- release heparin and proteases
Mediation of immediate-type hypersensitivity- IgE coated basophils release histamine and leukotrienes
- How long do monocytes spend in circulation?
- What are the functions of the monocytes?
Several days
Phagocytosis and antigen presentation to lymphoid cells Develop into macrophages (histiocytes) Macrophages store and release iron
- What do lymphoid stem cells give rise to?
- Where do B lymphocytes rise from?
- What cells can NK cells kill?
T cells, B cells and natural killer (NK) cells
Liver and bone marrow of the foetus Tumorous cells and virus-infected cells
- What are macrophages also known as?
- what are primary blood disorders?
- what are secondary changes?
Histiocytes
The leukocyte count/ morphology is abnormal due to acquired somatic DNA damage affecting a haematopoetic precursor cell
when a healthy bone responds to external stimulus such as infection, inflammation or infarction
- What is left shift?
- Numbers of which granulocyte does leukocytosis and leukopenia have the biggest impact on ?
An increase in non-segmented neutrophils or that there are neutrophil precursors (myelocytes) in the blood- a sign of neutrophilia
Changes in neutrophil count as this is usually the most abundant leukocyte in circulation
- What can neutrophilia be caused by?
Neoplasms - myeloproliferative disorders - Tumours produce granulocyte colony-stimulating factor (G-CSF) which skews the neutrophil retention/release balance in bone marrow
Infection -bacterial and especially pyogenic Corticosteroids Exercise - as a result of demargination of cells from the endothelial tissue or as part of phagocytic and inflammatory response Pregnancy - physiologic stress due to pregnant state Tissue damage
- What is Chronic Myeloid Leukaemia (CML)?
- What causes CML?
Increase in all granulocytes - neutrophils, eosinophils and basophils and their precursors in bone marrow and blood
myeloid precursor also produces RBCs- so increased RBC precursors too
Translocation between chromosomes 9 and 22 (BCR from 22 fuses with ABL1 on 9 to form a copy of BCR-ABL1 on both genes)
occurring in a single hemopoietic stem cell
fusion gene contributes to Tyrosine Kinase activity
drives autonomous cell proliferation
- What are key indicators that a patient has CML?
- How can the CML be potentially cured?
Enlarged spleen- pre mature RBCs sent to spleen for destruction
increase in all granulocytes and their precursors
BCR-ABL 1 protein signals between the cells surface and the nucleus
Can be inhibited by specific tyrosine kinase inhibitors as this prevents signal for cell division of the haemopoietic stem cell
- What can cause neutropenia?
Physiological basis - benign ethnic neutropenia
Radiotherapy/Chemotherapy Autoimmune disorders Infections Drugs
- What is neutrophil hypersegmentation?
- What causes neutrophil hypersegementation?
When there are more than 5 segments in the average of neutrophil lobes or segments (right shift)
Lack of Vitamin B12 and folate
- What causes eosinophilia?
- What is a cause of basophilia?
- What are some of the causes of monocytosis?
Allergy or parasitic infection e.g - asthma, eczema
Leukaemia
Leukaemia Infection or chronic inflammation Leukaemia
- How can you tell there is lymphocytosis in a blood film in infectious mononucleosis
May find atypical lymphocytes e.g -Epstein Barr virus infection (infectious mononucleosis)
lymphocytes have become basophiliated with granules RBC Cell membrane is loose and looks like it is 'hugging' surroundings, scalloped margins- both characteristics of infectious mononucleosis (glandular fever)
- What are the causes of a transient and then a persistent leukocytosis ?
Transient is in association with infection
eg Viral infection : lymphocytosis
parasitic: eosinophilia
bacterial: neutrophilia and monocytosis
Persistent is associated with leukaemia
- lymphoproliferative disorder CLL (lymphocytosis)
- CML (neutrophilia, basophilia, eosinophilia)
- What is Chronic Lymphocytic Leukaemia (CLL)?
- what is it caused by
Lymphoproliferative disorder
Leads to squashed lymphocytes Most common cause of persistent lymphocytosis in elderly Characterising profile of cell surface markers expressed by lymphocytes helps determine the cause of the lymphocytosis
- What is Acute Lymphoblastic Leukaemia (ALL)?
Increase in very immature cells (lymphoblast) with a failure of these to develop into mature lymphocytes
Bone marrow infiltrated by lymphoblast which then replace bone marrow cell (hemopoietic cells), resulting in impaired haemopoiesis and lymphoblast circulate in the peripheral blood Acute conditions are severe and sudden in onset
- What are the three possible treatments for ALL?
Transfusion - RBCs, Platelets and antibiotics
Systemic chemotherapy Intrathecal chemotherapy
Haematological features of ALL
what kind of mutations does acute leukaemia contain
thrombocytopenia (low platelet count)
Anaemia (normocytic, normochromic)
Leukocytosis
Lymphoblast increase
mutations in genes encoding transcription factors
results in an inability for cells to mature
so an accumulation of primitive cells called blast cells
- Name four causes of Lymphopenia
HIV Infection
Chemotherapy Radiotherapy Corticosteroids
