BIOT 309: BLOOD SMEAR PRACTICAL Feb., 2013

Microscopic Views Bird Blood Fish Blood Horse Blood Cat Blood Dog Blood Fish Blood Frog Blood Snake Blood Microscopic Views Human Blood Horse Blood

ASH Teaching Slides: Blood Cells Normal blood smear. The four larger cells shown are called granulocytes, a type of white blood cell. Maslak, P. ASH Image Bank 2008;2008:8-00067. Copyright ©2008 American Society of Hematology.

Photomicrograph of a Blood Smear Figure 10.2

Cells you will see Red blood cells, erythrocytes, no nucleus, transport O2 Platelets, deliver fibrin White blood cells, leukocytes: complete cells with a nucleus and organelles, defenders against disease,

Cell Differentiation and Lineages Granulocytes Granules in their cytoplasm can be stained Include neutrophils, eosinophils, and basophils Figure 10.4

Eosinophiles Function: Phagocytosis of antigen-antibody complexes; allergens Release enzymes to weaken or destroy parasites such as worms. Appearance: Nuceus has 2 large lobes

Basophil Appearance: Function: Secretes Histamine,( a vasodilator) Secretes heparin ( an anticoagulant)

Neutrophils Appearance Nucleus usually with 3-5 lobes in S-C shaped array Functions: Phagocytosis of bacteria Release of antimicrobial chemicals

Peripheral Smear Preparation Precaution: You need the right size drop to get a good smear Too large drop = too thick smear  too many cells Too small drop = too thin smear  too few cells Thick and thin also depend on (de)hydration, hematocrit (anemia)

Peripheral Smear Preparation The pusher slide is held securely with the dominant hand in a 30-45 deg angle. - quick, swift and smooth gliding motion to the other side of the slide creating a wedge smear

Peripheral Smear Preparation

Peripheral Smear Preparation Precautions: Ensure that the whole drop of blood is picked up and spread Too slow a slide push will accentuate poor leukocyte distribution, larger cells are pushed at the end of the slide Maintain an even gentle pressure on the slide – not doing so leads to ridges and valleys Keep the same angle all the way to the end of the smear.

Peripheral Smear Preparation Allow the blood smear to thoroughly dry – thicker will take longer Fix the blood smear with 70% methanol for 5 seconds; blot slide edge: let surface thoroughly dry Stain cells with Giemsa or Wright stain for 5’ - both are available; write in notebook which one you use – they color cells differently Dip slide in distilled water, 3 – 5 times Blot edge; thoroughly dry You are now ready to observe without and with microscope!!!

Feature of a Well Made Wedge Smear Smear is 2/3 or ¾ the entire slide Smear is finger shaped, very slightly rounded at the feathery edge: widest area of examination Lateral edges of the smear visible Smear is smooth without irregularities, holes or streaks When held up in light: feathery edge should show rainbow appearance Entire whole drop of blood is picked up and spread

See shape, internal morphology, comparative size, count cells, identify disease conditions

Peripheral Smear Examination Visual – no microscope: record in lab notebook Accurately draw both smears Measure length and width in mm Assess overall quality, i.e., Does it have a feathery edge? Fingerprint shape? Quality of the staining –also assess at Microscopic: 10x Objective record in lab notebook Observe types and distribution of the cells – use systematic approach, i.e., serpentine where do you find red blood cells; are they easily distinguished, i.e., separated Check lateral edges for WBC (white blood cells) distribution; do you see them distinctly Quick sketch of 2 different fields; label and describe cells

Choose the best areas for assessment Systematic search Back and forth serpentine or battlement track patterns are preferred – move the slide mount

Peripheral Smear Examination Microscopic: 40x Objective this week and next Determine correct area to view – cells spread apart but not too much Optimal Assessment Area: RBCs are uniformly and singly distributed Few RBC are touching or overlapping Normal biconcave appearance

Peripheral Smear Examination Too thin Too thick

Assessment at 40X Pick 5 fields that show different types of cells and sketch all cells; describe these cells in your own words Determine which cells you are seeing

Before you leave at 9:50 Make sure your slides have your student ID# Give to Younis; he will save for next week Clean up your area

Final Assessment – Next Week Microscopic: 100x objective, oil immersion