TISSUE
Tissue
Snap Frozen Tissue:
Frozen tissue refers to biological tissue that has been preserved by freezing it to very low temperatures, typically below -80 degrees Celsius (-112 degrees Fahrenheit) or even colder (-196 degrees Celsius). This preservation method maintains the integrity of the tissue for future analysis or experimentation. The samples are then stored in specialized freezers known as ultra-low temperature (ULT) freezers. These freezers maintain a constant temperature well below freezing to prevent tissue deterioration.
Availability: Around 9500 Frozen tumor tissues of 200mg aliquot each are available across all cancer indications. Matched plasma, FFPE blocks, unstained and stained slides, digital images can be made available on request. These samples are attached with complete clinical annotation.
Formalin-Fixed, Paraffin-Embedded Blocks ( FFPE Blocks ) :
FFPE stands for Formalin-Fixed, Paraffin-Embedded, which is a common method of preserving and preparing tissue samples for long-term storage and analysis in research, and pathology. Formalin fixation prevents tissue decay and microbial growth, this is followed by a series of processing steps ultimately embedding the tissue in liquid paraffin wax. Thin sections of the embedded tissue are cut and stained for microscopic examination. Downstream applications of FFPE are manifold like genomics, and proteomics wherein DNA, RNA, or proteins can be extracted from FFPE samples to study genetic mutations, gene expression patterns, and protein markers associated with diseases. FFPE blocks are the most widely requested biosamples due to their ease of storage and logistic stability. FFPE samples can be stored at room temperature for many years in archives and are the best resources for retrospective analysis.
Challenges with use of FFPE is that both over fixation and under fixation can lead to crosslinking between molecules and hamper greatly in DNA/RNA extractions. Loss of antigenicity during fixation can lead to false negative results in IHC , grossly affecting assay validations.
Availability: Whole blocks, curls, sections on slides can be provided on request across all cancer indications.
Viable Tissue:
Viable tissue refers to biological tissue which is composed of live cells along with their extracellular matrix and are capable of performing disease associated mechanisms. These are an ideal biosamples for developing patient-derived xenograft and organoids models to study tumor progression/invasion, immunoprofiling, and vaccine development. After surgical resection, specimens were minced 1-3mm pieces and, placed in FBS+10 % DMSO , and frozen using a slow freezing method (−1°C/min in −80°C) for 24 hours and then stored in liquid nitrogen.
Availability: Banked inventory contains around 20 viable tissues for immediate supply. However, most of the VT preparations are done prospectively.