1-11

Question 1

Name parameters measured by FACS (Fluorescence-activated cell scanner)

Answer 1

• Size of cell, granularity of cell, intensity of fluorescence - detectors of fluorescens

Question 2

Name two different types of IFA

Answer 2

• Direct immunofluorescence staining - the primary Ab is labelled with fluorescence dye - Indirect immunofluorescence staining - secondary reagent (antiglobulin or protein A/G labelled with fluorophore) is used to recognize a primary Ab - Advantages: identification of antigenic structures, identif. of different antigens in one sample, identif. of the live and dead bacteria in one sample, rapid method
• Disadvantages: requirement of expensive equipment and reagents and trained personnel Green fluorescence - live cells Red fluorescence - dead cells

Question 3

Granularity of cells in flow cytometry are detected by:

Answer 3

Side scatter

Question 4

Separation of leukocytes:

Answer 4

• Immunologically non-specific: size, density, electric charge, and adherence abilities - Immunologically specific: CD markers

Question 5

Separating solutions have specific density:

Answer 5

• 1,077 - 1,079 g/cm3

Question 6

Calculate the IPHA, index of phagocytic activity, if there are 340 particles per 100 phagocytes:

Answer 6

IPHA = 340 / 100 = 3,4

Question 7

Respiratory burst:

Answer 7

Activated phagocytes produce different antimicrobial and cytotoxic substances which can destroy ingested microorganisms. Mechanisms of killing dependent on oxygen - forming of free oxyden

Question 8

Failure of phagocytes results in:

Answer 8

• Retarded growth - Recurrent infections that tend to be prolonged - Lymphadenopathy - swelling of one or more lymph nodes

Question 9

Defect in phagocyte function are related to:

Answer 9

• Defects in mobilisation of leukocytes from their depots in bone marrow - Lack of receptors for chemotactic factors - Lack of adhesion molecules - Lack of generation of bactericidal agents to destroy bacteria

Question 10

How long is blood incubated with distilled water to get hypotonic solution?

Answer 10

• 35-40 seconds

Question 11

Compliment fixation test - what is detected?

Answer 11

• If patient has antibodies specific to Ag

Question 12

What marker is precent in B-lymhocytes?

Answer 12

CD19

Question 13

What is the number of leukocytes in Burks chamber if 88 leukocytes were counted in 50 squares? In 1 ml

Answer 13

• 88 * 105 leuk/ml