CTBS Tissue Processing & Preservation 3

Question 1

Which solution is most widely used for short-term hypothermic preservation of vascular allografts awaiting processing?

Accepted Answer

University of Wisconsin (UW) solution

Answer

UW solution contains impermeants, antioxidants, and buffers that minimize cell swelling and metabolic injury during cold ischemia.

Question 2

What is 'chondrocyte viability' most commonly assessed by in cartilage allografts?

Accepted Answer

Live/dead fluorescent dye exclusion assay

Answer

Live/dead fluorescent assays using calcein-AM (live) and ethidium homodimer (dead) dyes provide quantitative assessment of chondrocyte viability.

Question 3

Solvent/detergent (S/D) treatment of allograft tissue primarily inactivates which class of pathogens?

Accepted Answer

Enveloped viruses

Answer

S/D treatment disrupts lipid envelopes of viruses (such as HIV and HBV) but does not effectively inactivate non-enveloped viruses like parvovirus B19.

Question 4

Which AATB standard specifies the minimum acceptable residual moisture content for lyophilized tissues?

Accepted Answer

Less than 6%

Answer

AATB standards require residual moisture of less than 6% in lyophilized tissues to prevent microbial growth and degradation during ambient storage.

Question 5

A tissue bank uses peracetic acid (PAA) as a terminal sterilant. Which tissue type would be LEAST suitable for PAA treatment?

Accepted Answer

Viable corneal endothelium

Answer

PAA is an oxidizing agent that denatures proteins and destroys cell viability, making it incompatible with tissues intended to contain living cells.

(CTBS) Certified Tissue Bank Specialist Practice Test

(CTBS) Certified Tissue Bank Specialist Practice Test

CTBS Tissue Processing & Preservation 3