Wbc

Wbc is also know an leucocyte.Present in circulating blood. Defence mechanim of body.

1. WBC Ms Ankita R Bhatiya Assistant Professor Shree P.M.Patel COLLEGE OF PARAMEDICAL SCIENCE N TECHNOLOGY

2. It include: 1.What is WBC? 2.Calssification of wbc 3.Function of wbc . 4. Method for detection of wbc

3. What is wbc ?   It is derived from the  Greek  roots  leuk -  meaning "white" and  cyt -  meaning "cell". WBC is also called as Leucocyte they are the nucleated cells of our body which helping defence mechanism of our body. Chemical Composition: They are richly composed of nucleoprotein, lipids, ascorbic acid, glycogen & variety of enzyme.

4. wbc Total No. Or Total Count: Average count of total WBC is about 6,000 to 8,000/ cumm of blood & the normal range of total WBC is 4000 to 10,000/ cumm of blood. The average ratio of the total WBC with total red blood cell is about 1:700. That means one WBC there are 700 RBC.

5. Variation in normal count of WBC: Diurnal variation: The total count varies from day to day & even from hour to hour. In the morning or after rest the count is lowest. The count rises after mid-day & usually become highest in the evening up to night. Muscular exercise: In this condition total count is also increased. Emotional stress: Fear, pain, & anger increase the count. (Because of secretion of adrenalin hormone)

6. Variation in normal count of WBC: Age: In the new born, the count is highest about 20,000/ cumm of blood. After second week the count start falling but through out of infancy & childhood the count remains proportionally higher. Relation with pregnancy & labour: In pregnancy the count is highest 17,000/ cumm of blood. High altitude cause increases in total count. Asthma, skin disease will show increase in eosinophil count. Starvation & administration of certain chemical like benzene produce decrease in total count.

7. Classification of WBC: The various types of white blood cells found in circulating blood are given below. Based on morphological classification wbc is classified in two groups: 1. Granulocytes: The cell which contain granules in their cytoplasm is known as granulocyte . Neutrophil , Eosinophinln Basophile 2. Agranulocytes : The cell which not contain granules in their cytoplasm is known as agranulocyte . Large lymphocyte, small lymphocytes n monocyte

8. 1. Neutrophil :

9. 2. Eosinophil :

10. 3.Basophil

11. 4.Monocyte:

12. 5.Lymphocyte:

13. Function OF wbc : Leucocytes are needed by the body for its defence against invading organisms like bacteria, viruses, parasites, & cancer cells. It is mainly the neutrophils & the monocytes that attack & destroy viruses & bacteria in circulating blood. 1. Neutrophils : Neutrophils are called upon to act in acute infections. When there is an acute infection, neutrophils promptly come to the spot, cordon the area, phagocytize the organism & digest them. The circulating neutrophils adhere to the margins of the blood vessels & come out to act by throwing their pseudopodia into the pores in between the endothelial cells of the lining wall of capillaries.

14. Function OF wbc : 2. Monocytes : The circulating monocytes leave the intravascular compartment & form tissue macrophage. ( Monocyte enters the tissue they begin to swell & develop large no. of lysosomes in the cytoplasm. These cells are called macrophage.) These macrophages ingest mainly those bacteria which commonly produce chronic infections (e.g. Mycobacterium tuberculosis & Salmonella typhi ) 3. Lymphocytes : Lymphocytes are responsible for the phenomena called immunity. B- lymphocytes are ultimately converted into plasma cell, which produce immunoglobulins . The immunoglobulins combine with and neutralise bacteria & various toxic. material produced by invading organisms. Cellular immunity produces by T- lymphocytes. These cells combine directly with the bacteria, viruses, and cancer cells and destroy them.

15. Function OF wbc : 4. Eosinophils : These cells rise in allergic disorders & also in parasitic infections. The eosinophils can ingest antigen-antibody complexes, neutralize histamine & dissolve clots. A protein called 'major basic protein' present in the eosinophils destroy the larval parasites. 5. Basophils : The basophils of blood contain histamine, serotonin & heparin. During inflammation, histamine & serotonin are liberated by the damaged basophils . Histamine & serotonin are powerful vasodilators.

16. Method for wbc counting: AIM: Total leucocyte count by haemocytometer. Clinical Significance: Increase in total leucocyte count of more than 10,000/cumin is known as leucocytosis . The infections may be bacterial, viral, protozoal or parasitic. Decrease of less than 4,000/cumin is known as leukocytopenia . Certain viral & bacterial infections lead to leukocytopenia rather than leucocytosis .  

17. Method for wbc counting: Normal Range: Adults: - 4 ,000 - 10,000 / cumm At Birth: - 10,000-25000/ cumm 1 to 3 years: - 6,000 - 18,000/ cumm 4 to 7 years: - 6,000 - 15,000/ cumm 8 to 12 years: - 4,500 - 13,500 / cumm Requirements : Microscope, Neuberger’s chamber, Hb pipette, Test tube, WBC diluting fluid: It is prepared as follows: Glacial acetic acid - 2 ml, Gentian violet - 1 ml, Distilled water - 97 ml. This solution is stable at room temperature.

18. Method for wbc counting: Specimen: EDTA blood, capillary bloo Principle : The glacial acetic acid lyses the red blood cells while the gentian violet slightly stains the nuclei of the WBC. The blood specimen is diluted 1:20 with the diluting fluid & the cells are counted under low power of microscope by using counting chamber. The number of cells in undiluted blood is reported per cumin (Cubic millimetre) of whole blood.

19. Procedure: 1) Identify the right patient. 2) Collect all the requirement. 3) Do labelling . 4) Collect the blood with the help of capillary or vein puncture. 5) In a labelled test tube take 0.38 ml WBC diluting fluid. 6) Add 0.02 ml of blood with the help of Hb pipette and use dry cotton to wipe excess blood on the pipette. 7) Mix well & keep it for 5 minutes. 8) Fill the Neuberger’s chamber & allow the cells to settle for 2-3 minutes. 9) Focus on one of the 'W' marked areas (each having 16 small squares) by turning objective to low power (I0X) 10] Count cells in all four 'W' marked corner squares. 10) Do calculation. 12) Clean the working area. 13) Put all the requirements back to its place. 14) Wash the hands.

20. WBC Calculation: Number of WBC / cumm = No of cell counted X dilution ---------------------------------------- Area counted X Death of fluid Dilution= Total volume ------------------- Blood volume =No of cell counted X 20 --------------------------------- 4 X 0.1 = No of cell counted X 50 =----------------- wbc cell/ cumm

21. WBC Precaution: The counting chamber should be clean & dry. Diluting fluid is draw up to the mark & care is taken not to allow air bubbles to enter. The filling of the chamber should be done in one application of the tip of the pipette. Air bubbles should not be present under the coverslip . The diluting fluid should not over run the coverslip . Longer waiting leads to drying of the fluid and disturb the cells. Before the counting the condenser & mirror of the microscope should be properly' adjusted. In case of WBC counting extra care is taken during the preparation & storage of WBC diluting fluid. It should be perfectly free from dust particles & yeast cells otherwise falsely high count are obtained.