Different type of immunologic cells are involved against pathogen......here about different types of immolune system cell are showing on the basis of their origin and function

1. CELLS INVOLVES IN IMMUNITY
UTTARAN MODHUKALYA
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2. CONTENT
1. INTRODUCTION
2. HEMATOPOIETIC STEM CELL
3. LYMPHOCYTE CELL
4. MYELOID CELL
5. REFERENCE
6. CONCLUSION
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3. INTRODUCTIO
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• Immunity is the ability of the body to protect against all types of
foreign bodies like bacteria, virus, toxic substance etc. Immunity is
of two types i.e, innate and acquired immunity. Innate immunity is
inherited by the organism from the parents and protect it from birth
throughout life and The immunity that an individual acquires after
birth is called adaptive or acquired immunity. The cells involves in
immunity are originated from bone marrow(bursa of fabricius in
case of bird) and thymus where each cell having different function
to protect the body against the antigenic substance.
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4. HEMATOPOIETIC STEM CELL
• All the blood and lymphoid cell arise from a type of cell called
hematopoietic stem cell. Then this cell differentiated into myeloid
progenitor cell and lymphoid progenitor cell.
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5. HEMATOPOIETIC STEM CELL
• Further the lymphoid progenitor cell differentiated into B-
cell, T-cell, Natural killer cell and dendritic cell. On the other
hand the myeloid progenitor cell is differentiated into
eosinophil, basophil, neutrophil, macrophage, mast cell and
dendritic cell, erythrocyte, platelets. The lymphoid cell are
central cell that directly involve in immunoresponse.
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6. LYMPHOCYTE CELL
Lymphocyte constitute 20-40% bodies WBC cells and 99% of the cells
in the lymph. The lymphocyte constantly circulate in the blood and
lymph. On the basis of function and cell membrane components
lymphocyte can be divided into three types-
1. B- lymphocyte
2. T- lymphocyte
3. Natural Killer cell
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7. B-LYMPHOCYTE
CELL
This type of cell directly involved in immunoresponse. B-cell originate
from the organ Bursa of fabricius in bird and bone marrow in
mammals through the lymphoid progenitor cell. When B lymphocytes
is mature then it produce antibody so, this immunity is called antibody
mediated or humoral immunity. Formation of plasma B-cell and
memory B-cell : When antibodies on B-cell’s surface bind antigen the
B-cell is activated and produced daughter B-cell which later give rise
to plasma B-cell and memory B-cell. This phenomenon is called clonal
selection.
1. Plasma cell: It become enlarged and secrete enormous
amounts of body and lives only for few days.
2. Memory B-cell : It remains as memory cell and having longer
life span.
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8. T-LYMPHOCYTES
CELL
T-lymphocyte originated in the bone marrow but develop in the thymus.
T-cell also have membrane receptors for antigen which are not
structurally similar to antibody. This receptor are called T-cell
receptor(TCR) which doesn't recognised free antigen. They recognise
antigen bound to MHC proteins. Displayed on cell surface. It is of two
types- TH-cell(T helper cell) and Tc-cell(T cytotoxic cell). TH-cell helps
phagocytic to kill microbes and help B-cells to make antibodies
against that microbes. Tc-cell kill infected cell of the body and
eliminated the reservoir of infection.
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9. NATURAL KILLER
CELL
Natural killer cell are large granular lymphocytes constitute
about 5-10% of total lymphocytes. NK cells differentiated
in bone marrow, thymus, spleen, lymph nodes etc. It kills
the cells infected by virus through blocking replication of
virus. NK cells doesn't express receptor like B-cell, T-cell.
Their cytoplasm contain perforin and protease.
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10. MYELOID PROGENITOR CELL
It develops monocytes(dendritic cell, mast cell and macrophage),
granulocytes (basophil, eosinophil, neutrophil) etc.
A] Granulocytic cell: The granulocyte cell include basophil,
eosinophil, neutrophil. They produced in the bone marrow through
the myeloid progenitor cell.
1. Neutrophil: The neutrophil are active phagocytic cells They have
multilobed nucleus. 40-75% of WBC are neutrophil. They target the
bacterial and fungal antigens and kill them either by phagocytosis.
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11. MYELOID PROGENITOR CELL
2]Eosinophil: They constitute 1 to 6% of total WBC. They have
bilobbed nucleus and 8 to 12 days of life span. They carryout
degranulation reaction, release enzyme, growth factors and
cytokines. They are involved in reaction again parasites and
allergic substances.
3]Basophil: Their percentage in WBC is less than 1. They release
histamine, enzyme, cytokines which are involved in body defence.
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12. MYELOID PROGENITOR CELL
• Monocytes:
1] Mast cell: The mast cell are involved in allergic reaction, composition
in total WBC for mast cell is very low.
2] Dendritic cell: The dendritic cells have elongated extension. They
may be produced from myeloid progenitor or lymphoid progenitor.
Their main function in adaptive immunity is as a antigen presenting
cell.
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13. FIG : LYMPHOID AND MYELOID CELL CLASSIFICATION13

14. MECHANISM
ANTIGEN
MACROPHAGE
ANTIGEN PRESENTING CELL
HELPER T-CELL
B-CELL MEMORY T-CELL CYTOTOXIC T-CELL
PLASMA B-CELL MEMORY B-CELL KILL INFECTED
CELL
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15. CONCLUSION
• From the above discussion we have concluded that various types
of cells are involved when a microbes/pathogen enters to our
body. Mainly we can say that some cells are involved to go
against pathogen directly e.g, Macrophage. Some are involved
against pathogen infected cell for kill e.g, cytotoxic T-cell. Some
cells help to kill pathogen to other cell e.g, Helper T cell. Some
cell produces antibody directly i.e, plasma B- cell
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