Special Studies Of White Blood Cells (WBC)
WBC (White Blood
Cells)
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White blood cells have a nucleus surrounded by cytoplasm. All WBCs come from bone marrow stem cells-> ((Cells that are able to develop into many (or all) types of cells)). In the marrow, they change into two groups: myeloid and lymphoid cells. They then mature into five different types of WBCs.
White blood cells have a nucleus surrounded by cytoplasm. All WBCs come from bone marrow stem cells-> ((Cells that are able to develop into many (or all) types of cells)). In the marrow, they change into two groups: myeloid and lymphoid cells. They then mature into five different types of WBCs.
The name neutrophil derives from staining characteristics on hematoxylin and eosin (H&E) histological or cytological preparations. Whereas basophilic white blood cells stain dark blue and eosinophilic white blood cells stain bright red, neutrophils stain a neutral pink. Normally, neutrophils contain a nucleus divided into 2–5 lobes.
Neutrophils are a type of phagocyte and are normally found in the bloodstream. During the beginning (acute) phase of inflammation, particularly as a result of bacterial infection, environmental exposure,[4] and some cancers,[5][6] neutrophils are one of the first-responders of inflammatory cells to migrate towards the site of inflammation. They migrate through the blood vessels, then through interstitial tissue, following chemical signals such as Interleukin-8 (IL-8), C5a, fMLP and Leukotriene B4 in a process called chemotaxis. They are the predominant cells in pus, accounting for its whitish/yellowish appearance.
Neutrophils are recruited to the site of injury within minutes following trauma, and are the hallmark of acute inflammation
Microscopic Finding Neutrophil
2. Eosinophil:-
Eosinophil granulocytes, usually called eosinophils or eosinophiles (or, less commonly, acidophils), are white blood cells and one of the immune system components responsible for combating multicellular parasites and certain infections in vertebrates. Along with mast cells, they also control mechanisms associated with allergy and asthma. They are granulocytes that develop during hematopoiesis in the bone marrow before migrating into blood.In Normal Individuals, eosinophils make up about 1-6% of white blood cells, and are about 12-17 micrometers in size.[1] They are found in the medulla and the junction between the cortex and medulla of the thymus, and, in the lower gastrointestinal tract, ovary, uterus, spleen, and lymph nodes, but not in the lung, skin, esophagus, or some other internal organs[vague] under normal conditions. 
3. Basophil:-
Basophil granulocytes, mostly referred to as basophils, are the least common of the granulocytes, representing about 0.01% to 0.3% of circulating white blood cells Basophils contain large cytoplasmic granules which obscure the cell nucleus under the microscope when stained. However, when unstained, the nucleus is visible and it usually has two lobes. The mast cell, another granulocyte, is similar in appearance and function. Both cell types store histamine,
a chemical that is secreted by the cells when stimulated. However, they
arise from different cell lines, and mast cells usually do not
circulate in the blood stream, but instead are located in connective
tissue. Like all circulating granulocytes, basophils can be recruited
out of the blood into a tissue when needed.
The name comes from the fact that these leukocytes are basophilic, i.e., they are susceptible to staining by basic dyes, as shown in the picture.
4. Monocyte:-
Monocytes are a type of white blood cells (leukocytes). They are the largest of all leukocytes. They are part of the innate immune system of vertebrates including all mammals (humans included), birds, reptiles, and fish. They are amoeboid in shape, having clear cytoplasm. Monocytes have bean-shaped nuclei that are unilobar, which makes them one of the types of mononuclear leukocytes (agranulocytes). Monocytes constitute 2% to 10% of all leukocytes in the human body. They play multiple roles in immune function. Such roles include: (1) replenishing resident macrophages under normal states, and (2) in response to inflammation signals, monocytes can move quickly (approx. 8–12 hours) to sites of infection in the tissues and divide/differentiate into macrophages and dendritic cells to elicit an immune response. Half of them are stored in the spleen[1] (except in people who have undergone splenectomy). Monocytes are usually identified in stained smears by their large kidney shaped or notched nucleus. These change into macrophages after entering into the tissue spaces.
Monocytopenia Monocytopenia is a form of leukopenia associated with a deficiency of monocytes.
A lymphocyte is any of 3 types of white blood cell in a vertebrate's immune system. All 3 are agranulocytes. They include natural killer cells (Natural Killer cells) (which function in cell-mediated, cytotoxic innate immunity), T cells (for cell-mediated, cytotoxic adaptive immunity), and B cells (for humoral, antibody-driven adaptive immunity). They are the main type of cell found in lymph, which prompted the name lymphocyte.
T cells and B cells
Main articles: T cell and B cell
T cells (thymus cells) and B cells (bursa-derived cells[1]) are the major cellular components of the adaptive immune response. T cells are involved in cell-mediated immunity, whereas B cells are primarily responsible for humoral immunity (relating to antibodies). The function of T cells and B cells is to recognize specific “non-self” antigens, during a process known as antigen presentation. Once they have identified an invader, the cells generate specific responses that are tailored to maximally eliminate specific pathogens or pathogen-infected cells. B cells respond to pathogens by producing large quantities of antibodies which then neutralize foreign objects like bacteria and viruses. In response to pathogens some T cells, called T helper cells, produce cytokines that direct the immune response, while other T cells, called cytotoxic T cells,Natural killer cells
Main article: Natural killer cell
NK cells are a part of the innate immune system and play a major role in defending the host from both tumors and virally
infected cells. NK cells distinguish infected cells and tumors from
normal and uninfected cells by recognizing changes of a surface molecule
called MHC (major histocompatibility complex) class I. NK cells are activated in response to a family of cytokines called interferons. Activated NK cells release cytotoxic (cell-killing) granules which then destroy the altered cells. They were named "natural killer cells" because of the initial notion
that they do not require prior activation in order to kill cells which
are missing MHC class I.
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