WBC PPT

Views:
 
Category: Education
     
 

Presentation Description

No description available.

Comments

Presentation Transcript

White Blood Cells:

White Blood Cells

Introduction :

Introduction White blood cells (WBCs), or leukocytes (also spelled "leucocytes," " leuco -" being Greek for white), are cells of the immune system involved in defending the body against both infectious disease and foreign materials. Five different and diverse types of leukocytes exist, but they are all produced and derived from a multipotent cell in the bone marrow known as a hematopoietic stem cell. Leukocytes are found throughout the body, including the blood and lymphatic system.

Classification :

Classification Leucocytes Granulocytes Agranulocytes 1). Neutrophils 1). Monocytes 2). Eosinophils 2). Lymphocytes 3). Basophils a).Small lymphocyte b).Large lymphocytes

Normal counts:

Normal counts 1). Neutrophils (50-70%) – 3000 to 6000 cells/ cumm 2). Eosinophils (1-4%) – 150 to 300 cells/ cumm 3). Basophils (< 1%) – 10 to 100 cells/ cumm 4). Monocytes (2-8%) – 300 to 600 cells/ cumm 5). Lymphocytes(20-40%) – 1500 to 2700 cells/ cumm a).Small lymphocyte b).Large lymphocytes At birth – 20,000/ cumm ; count decreases after 2 nd week, reaching noral adult value at 5-10 years. In adults – 4000 to 11000/ cumm

Neutrophil:

Neutrophil Polymorphonuclear neutrophils 10-14 µm diameter Young neutrophil has single horse shaped nucleus which becomes lobed as it grows. Mature neutrophil is purple in colour & multilobed (2-6 lobes). Lobes are connected by chromatin filaments. Cytoplasm is pale bluish & full of fine granules. Granules take both acidic & basic stain & look violet-pink colour . Are lysosomal in origin & contain sulpatases nucleases & proteolytic enzymes.

Functions :

Functions Phagocytosis : when the body gets invaded by bacteria, neutrophils are the first cells to seek out to ingest & kill the bacteria. They are body’s first line of defences . They contain a fever-producing substance, endogenous pyrogens which is an important mediator of febrile response to bacterial pyrogens .

Eosinophil :

Eosinophil 10-14 µm in diameter Nucleus is purple in colour & bilobed in 85% of the cells. Two lobes are connected by chromatin strands & thus has spectale shaped. The remaining 15% have trilobed nucleus. Cytoplasm is acidophilic & appears bright pink in colour , it contains coarse deep red staining granules which don’t cover nucleus. The granules contain basic protein & stain ore intensely for peroxidase . The granules contain histamine, lysosomal enzymes & eosinophil chemotactic factor of anaphylaxis.

Functions :

Functions Has mild phagocytosis action. ECF-A is a chemical mediator of immediate hypersensitivity reactions. Eosinophil collect at the sites of allergic reaction & limit their intensity by degrading the effects of mediators. They enter the tissues & provide mucosal immunity. They attack parasites that are too large to be engulfed by phagocytosis . Eosinophil granules release chemicals which are toxic to larvae of parasites.

Basophil :

Basophil 10-14 µm in diameter Nucleus is irregular, may be bilobed or trilobed , & boundary is not well defiened because of over crowding with coarse granules. Cytoplasm is slightly basophilic & appears blue & full of granules. Granules are very coarse & stain deep purple or blue with basic dye. Granules are plenty & completely fill the cell & overload the nucleus. The granules contain heparin, histamine & 5- HT.

Functions :

Functions Mild phagocytosis Liberates histamine which leads to allergic manifestations. Liberates heparin which; i ). Acts as anti-coagulant & keeps the blood in fluid state in the body ii). Activates a hormone, lipoprotein lipase which facilitates absorption of triglycerides after meals.

Monocyte :

Monocyte Monocyte is the largest mature leucoyte & measures 12-20 µm in diameter. Nucleus is large, single & eccentric in position. Horse shoe shaped & indented. Appears oval in side view. Nuleus has fine reticular chromatin network. Cytoplasm is abundant, pale blue & usually clear but some ties contain fine dust-like granules called azur granules which may be few or numerous.

Functions :

Functions Active phagocytosis . They are 2 nd line of defence . Phagocytic mechanism is same as seen in neutrophil . Monocytes enter the circulation fro bone marrow but after 72 hours they enter the tissues to become ‘tissue macrophage’. They also kill tumour cells after sensitization by lymphocytes. They synthesize complement & other biologically important substances.

Small lymphocyte:

Small lymphocyte 7-10 µm in diameter. It has large round, single nucleus which almost completely fill the cytoplasm. Stains blue very deeply giving ink-spot appearance. Chromatin is coarsely clumped & shapeless. Cytoplasm is scanty, seen as crescent of clear light blue colour arround the nucleus. Cytoplasm does not contain visible granules.

Large lymphocyte:

Large lymphocyte 10-14 µm in diameter It has large round, single nucleus which almost completely fill the cytoplasm. Stains blue very deeply giving ink-spot appearance. Chromatin is coarsely clumped & shapeless. Cytoplasm is scanty, seen as crescent of clear light blue colour arround the nucleus. Cytoplasm does not contain visible granules.

Functions :

Functions Produces antibodies i.e ; immune substanes specially in delayed hypersensitivity reactions.

PowerPoint Presentation:

Thank you

authorStream Live Help