OMS Atlas OCT Spatial Mapping - Limited

Verify the identity of the OCT block to be cut against written request for sectioning.

Remove OCT block from -80°C freezer and acclimate to cryostat (-20°C ) for minimum of 3h 0m 0s.

Label all slides and cryotubes with a unique BEMS ID and Part#, corresponding to the written request and OCT spatial map (below).

A	B	C	D	E
Part#	Description	Thickness	Assay	Recipient
1	Superfrost Plus slide	5µm	HE	OHSU, HSR
2	Superfrost Plus slide	5µm	Cyclic Immunofluorescence (Tumor Panel)	HMS, Alyce Chen
3	Superfrost Plus slide	5µm	Cyclic Immunofluorescence (Tumor Panel)	HMS, Alyce Chen
4	Remainder of OCT block	NA	Single Cell Indexing ATAC Sequencing	OHSU, Andrew Adey

Affix OCT block to cryostat chuck.

Orient and face block to get adequate amount of core.

Note: Avoid excessive facing to reduce tissue loss.

Set cryostat to 5 micron sections.

Note: All sections cut from here on should be sequential. The serial order, adjacency, and consistent orientation of the sections are all important factors. Please note any deviations from the protocol.

Cut three sections at 5 microns (Part#1-3) and affix onto appropriately labeled slide according to OCT spatial map (step #3 above).

Place all slides and remaining OCT block in -80°C freezer.

Note: No slides are to be fixed under this protocol.

Perform hematoxylin and eosin (H&E) staining on slide labeled Part#1 (see OCT spatial map in step #3 above).

Deliver unstained slides (Part#2 and 3) and remainder OCT block (Part#4) to BioLibrary for distribution.

Note: Keep samples frozen at all times. Store at -80°C . Transfer/ship on dry ice.