# US 2024/0201170 A1 · Maintenance and/or culture of tissue slices in vitro or ex vivo > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2024/0201170 A1 - Document ID: US20240201170A1 - Status: Published application - Kind: A1 - Application number: 18/555,348 - Filed: 2022-04-18 - Published: 2024-06-20 - Earliest claimed: 2021-04-16 - Assignees: National University of Singapore; Singapore Health Services Pte Ltd - Applicants: National University of Singapore; Singapore Health Services Pte Ltd - Inventors: Li Shan Eliza FONG; Christabella ADINE; Narayanan Gopalakrishna IYER - Web page: https://patentgrep.com/patent/US20240201170A1 ## CPC - G01N 33/5011: {for testing antineoplastic activity} - C12N 5/0693: {Tumour cells; Cancer cells} - G01N 33/5082: {Supracellular entities, e.g. tissue, organisms} - C12N 5/0068: {General culture methods using substrates (for specific animal cell type C12N5/06)} - C12N 2500/50: Soluble polymers, e.g. polyethyleneglycol [PEG] - C12N 2501/727: Kinases (EC 2.7.) - C12N 2533/50: Proteins - C12N 2533/80: Hyaluronan - C12N 2533/90: Substrates of biological origin, e.g. extracellular matrix, decellularised tissue - C12N 2537/10: Cross-linking - G01N 2500/10: involving cells - G01N: INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES (measuring or testing apparatus or processes other than immunoassay, involving enzymes or microorganisms C12M, C12Q) - C12N: MICROORGANISMS OR ENZYMES; COMPOSITIONS THEREOF; PROPAGATING, PRESERVING, OR MAINTAINING MICROORGANISMS; MUTATION OR GENETIC ENGINEERING; CULTURE MEDIA (microbiological testing media C12Q1/00) ## Abstract The present invention relates to the maintenance and/or culture of tissue slices in vitro or ex vivo. In particular, the present invention relates to a method for the maintenance and/or culture of tissue slices using hydrogels. In one embodiment, the hydrogel is a semi-synthetic hydrogel comprising thiolated hyaluronan with acrylated peptides comprising KGGGPQGIWGQGK (SEQ ID NO: 1) that are degradable by matrix metalloproteinases. In particular, the present invention provides a platform suitable for downstream analysis such as real-time imaging, other real-time study of the tissue in culture and testing of a therapeutic agent or a potential therapeutic agent. ## Claims ### Claim 1 A method for maintaining and/or culturing tissue slices; comprising: (i) providing a tissue slice; (ii) providing a hydrogel comprising conjugated peptides; (iii) placing the tissue slice onto the hydrogel comprising conjugated peptides; and (iv) maintaining and/or culturing the tissue slice on the hydrogel using a culture medium. ### Claim 2 (depends on 1) The method according to claim 1, wherein the hydrogel comprises a hyaluronan, collagen or gelatin modified with at least one chemical group. ### Claim at position 3 3-7. (canceled) ### Claim 8 (depends on 2) The method according to claim 2, wherein the chemical group is for crosslinking the hydrogel. ### Claim at position 5 9-10. (canceled) ### Claim 11 (depends on 8) The method according to claim 8, wherein the hydrogel comprises thiolated hyaluronan with conjugated peptides. ### Claim 12 (depends on 1) The method according to claim 1, wherein the peptides are for crosslinking the hydrogel and/or presenting/providing biochemical cues, and/or wherein the peptides comprise a peptide degradable by matrix metalloproteinases or other proteases. ### Claim at position 8 13-14. (canceled) ### Claim 15 (depends on 1) The method according to claim 1, wherein the peptides comprise the sequence PQ. ### Claim 16 (depends on 1) The method according to claim 1, wherein the peptides comprises the sequence KGGGPQGIWGQGK (SEQ ID NO: 1) or a scrambled derivative. ### Claim 17 (depends on 1) The method according to claim 1, wherein the hydrogel further comprises at least one further set of peptides. ### Claim 18 (depends on 17) The method according to claim 17, wherein the at least one further set of peptides present/provide biochemical cues. ### Claim 19 (depends on 17) The method according to claim 17, wherein the at least one further set of peptides comprise one or more types of extracellular matrix protein or peptides comprising a peptide sequence derived from an extracellular matrix protein, and wherein the extracellular matrix protein comprises fibronectin, collagen and/or laminin. ### Claim 20 (canceled) ### Claim 21 (depends on 19) The method according to claim 19, wherein the at least one further set of peptides comprises the sequence RGD or a scrambled derivative. ### Claim 22 (depends on 21) The method according to claim 21, wherein the at least one further set of peptides comprises the sequence GRGDS (SEQ ID NO: 2) or a scrambled derivative. ### Claim at position 17 23-26. (canceled) ### Claim 27 (depends on 1) The method according to claim 1, wherein the peptides comprise acrylated peptides. ### Claim 28 (depends on 11) The method according to claim 11, wherein attaining the desired stiffness of the hydrogel comprising conjugated peptide depends on the concentration of the hyaluronan in the hydrogel. ### Claim 29 (depends on 11) The method according to claim 11, wherein attaining the desired stiffness of the hydrogel comprises or further comprises increasing or decreasing the concentration of crosslinkers in the hydrogel. ### Claim 30 (depends on 1) The method according to claim 1, wherein step (iii) comprises placing the tissue slice on the hydrogel as crosslinking of the hydrogel takes place for achieving mechanical fixation of the tissue slice in the hydrogel. ### Claim 31 (depends on 1) The method according to claim 1, wherein step (iv) comprises contacting the hydrogel with the culture medium, and wherein the hydrogel is substantially submerged with the culture medium and the tissue slice is partially submerged with the culture medium. ### Claim at position 23 32-33. (canceled) ### Claim 34 (depends on 1) The method according to claim 1, wherein the culture medium comprises at least one ROCK inhibitor. ### Claim at position 25 35-37. (canceled) ### Claim 38 (depends on 1) The method according to claim 1, further comprising testing the effect of at least one therapeutic agent or potential therapeutic agent on the tissue slice. ### Claim at position 27 39-42. (canceled) ### Claim 43 (depends on 1) The method according to claim 1, wherein the at least one tissue slice comprises a tissue slice from a tumour.