1. BIOT 309: BLOOD SMEAR PRACTICAL
Feb., 2013

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

3. 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: Copyright ©2008 American Society of Hematology.

4. Photomicrograph of a Blood Smear
Figure 10.2

5. 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,

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

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

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

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

10. 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)

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

12. Peripheral Smear Preparation

13. 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.

14. 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!!!

15. 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

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

18. 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

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

20. 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

21. Peripheral Smear Examination
Too thin
Too thick

22. 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

23. 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

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