Name	Type	Attributes	Definition
tissue_processing	string	required, nullable	Enzymatic digestion and/or physical methods used to isolate cells from sample
cell_subset	:ref:`Ontology <OntoVoc>`	required, nullable	Commonly-used designation of isolated cell population
cell_phenotype	string	required, nullable	"List of cellular markers and their expression levels used to isolate the cell population.
"
cell_label	string	optional, nullable	"Free text cell type annotation. Primarily used for annotating cell types that are not  provided in the Cell Ontology.
"
cell_species	:ref:`Ontology <OntoVoc>`	optional, nullable	"Binomial designation of the species from which the analyzed cells originate. Typically, this value should be identical to `species`, in which case it SHOULD NOT be set explicitly. However, there are valid experimental setups in which the two might differ, e.g., chimeric animal models. If set, this key will overwrite the `species` information for all lower layers of the schema.
"
single_cell	boolean	required, nullable	TRUE if single cells were isolated into separate compartments
cell_number	integer	required, nullable	Total number of cells that went into the experiment
cells_per_reaction	integer	required, nullable	Number of cells for each biological replicate
cell_storage	boolean	required, nullable	TRUE if cells were cryo-preserved between isolation and further processing
cell_quality	string	required, nullable	Relative amount of viable cells after preparation and (if applicable) thawing
cell_isolation	string	required, nullable	Description of the procedure used for marker-based isolation or enrich cells
cell_processing_protocol	string	required, nullable	"Description of the methods applied to the sample including cell preparation/ isolation/enrichment and nucleic acid extraction. This should closely mirror the Materials and methods section in the manuscript.
"