2 Primary cells Flashcards
antigens
substances that can trigger or generate immune response. Substance that the immune system can specifically recognize with the help of antigen receptors expressed on lymphocytes
haptens
simple organic substances that can be recognised by the immune system but cannot trigger immune reactions. The immune response can only be triggered if the hapten is chemically bound to a complex molecule (carrier).
bacterial cell walls and antigens within
antigens within
in capsid huge amounts of different proteins, polysaccharide – LPS
easy target for immune system – does not recognise – easy for immune system to create antibodies against e.g. PPG and LPS
humoral x cellular
Antibodies -WBC produce the immunity
Complement
Everything in the immune system is a cellular response
humoral x cellular immunity
white blood cell is alerted to the presence of unwanted bacteria in the blood, it will find this bacterium and surround it as an amoeba does with food. After the white blood cell (or T cell) has the bacteria trapped, it releases a deadly toxin that destroys the bacteria by breaking its outer membrane
cellular theory of immunity
1880s Eli Metchnikoff - phagocytosis by cells of Jellyfish, they are important to immune reactions
Gowan’s findings
Gowans and coworkers, using thoracic duct drainage where lymph of animals had been diverted, observed test animals unable to respond antigen challenges and failed to recognise grafts. When the white blood cells were replenished the function was restored.
where are cells from
all cells for immune system from bone marrow, all inflammatory and ancillary cells work with primary cells of immune system derive from pluripotent stem cells
pluripotent stem cells
gives rise to a lymphoid stem cell and a myeloid stem cell
lymphoid stem cell
differentiates into three types of cells - T lymphocyte, the B lymphocyte, and the non-T, non-B natural killer (NK) cell progenitor- and contributes to the development of subsets of dendritic cells
myeloid stem cell
gives rise to:
- dendritic cells
- mast cells
- basophil
- neutrophils
- eosinophils
- monocytes
- macrophages
- megakaryocytes
- erythrocytes
stem cell differentiation
Differentiation of these committed stem cells is critically dependent on an array of cytokines and cell-cell interactions
Origin of cells in Immune system
Liver - major site of foetal hematopoiesis
Bone marrow remains primary site of hematopoiesis in adults
liver in immune cell formation
is in the liver until shortly before birth when stem cells travel by blood to the spleen that supports hematopoiesis until vascular invasion of cartilaginous bones begins the process of ossification and formation of marrow cavity
bone marrow in immune cell formation
until death, some hematopoietic stem cells in connective tissue of the abdominal mesenteries can be induced to form hematopoietic colonies by cytokines released during inflammation
