Leucocytes Flashcards
What are leukocytes?
White blood cells that play a key role in the immune response
Includes various types such as neutrophils, monocytes, and lymphocytes
What are the two main series of leukocytes?
Lymphoid series and myeloid series
Lymphoid series includes lymphocytes; myeloid series includes granulocytes and monocytes
What do lymphoid stem cells branch into?
T lymphocytes - (thymus)
NK lymphocytes
B lymphocytes
What is the function of NK lymphocytes?
Natural killer cells (NK cells) are white blood cells that destroy infected and diseased cells, like cancer cells.
What do myeloid stem cells branch into?
Erythocytes
Megakaryocytes
Monocytes
Granulocytes
What is granulopoiesis?
The process of neutrophil maturation in the bone marrow
Involves stages such as myeloblast, promyelocyte, myelocyte, band neutrophil, and segmented neutrophil
What is the maturation order of neutrophils?
Myeloblasts,
Promyelocytes,
Myelocytes,
Metamyelocytes,
Bank neutrophils,
Neutrophils.
In what myeloid cells are there rapid cell division?
Myeloblasts and promyelocytes
What is G-CSF?
Granulocyte colony stimulating factor
What is the role of neutrophils?
Search, ingest, and destroy bacteria
Usually occurs in tissues during infections
What is ‘shift to left’ in neutrophils?
A shift to immaturity of neutrophils in response to infection
Indicates increased presence of younger neutrophil forms
What causes neutropenia?
Bone marrow disease, drug side effects, viral infections, genetic neutropenia
Neutropenia is defined as a neutrophil count of less than 1.9 x 10^9/L
What is eosinophilia?
An increased eosinophil count greater than 0.4 x 10^9/L
Associated with parasitic infections and allergic reactions
What are monocytes and their function?
They become macrophages in tissues, responsible for phagocytosis
Types include histiocytes, Kupffer cells, alveolar macrophages, microglial cells, and osteoclasts
What does monocytosis indicate?
An increase in monocytes greater than 1.0 x 10^9/L
Often due to chronic inflammatory states or myelodysplastic syndrome
What is the significance of the terms -osis, -philia, and -penia?
-osis indicates too many, -philia indicates tendency, -penia indicates deficiency
Examples include neutrophilia, lymphocytosis, and neutropenia
What is the clinical utility of basophils?
They are involved in immunity against worms and regulate allergic inflammation
Their count is seldom useful clinically
What does a leukoerythroblastic blood film indicate?
Presence of immature white and red blood cells, suggests severe bone marrow disease
Can be caused by leukaemia, lymphoma, or severe hypoxia
What are the three main cell types in blood?
T cells, B cells, NK cells
T cells comprise ~60-80%, B cells ~15-30%, NK cells ~5-10%
What is lymphocytosis and its significance?
An increase in lymphocytes, significance varies by age
In children, often due to viral infections; in older adults, often related to CLL
What is the role of G-CSF?
Stimulates neutrophil production after chemotherapy
Granulocyte colony-stimulating factor is crucial in recovery from neutropenia
What is cancer in the context of blood disorders?
A clonal proliferation due to genetic mutations affecting growth and cell death
Can lead to bone marrow failure and associated conditions like pancytopenia
What are the types of myeloid cancers?
Acute Myeloid Leukaemia, Myeloproliferative neoplasms, Myelodysplastic syndrome
Each has distinct characteristics and prognosis
What are examples of lymphoid cancers?
Acute Lymphoblastic Leukaemia, Lymphoma, Chronic Lymphocytic Leukaemia, Plasma cell myeloma
Reflect behaviors of the originating cell type
