CCIDB: A Manually Curated Cell-Cell Interaction Database
with Cell Context Information

    Cell-cell interaction (CCI) is a crucial event in the development and function of multicellular organisms. The development of CCI databases is beneficial for researchers who want to analyze single-cell sequencing data or study CCI through molecular experiments. CCIs are known to act differently according to cellular and biological contexts such as cell types, gene mutations, or disease status; however, previous CCI databases do not completely provide this contextual information pertaining to cell-cell interactions. We constructed a cell-cell interaction database (CCIDB) containing the biological and clinical contexts involved in each interaction. To build a database of cellular and tissue contexts, we collected 38 types of context features, which were categorized into seven categories, including “interaction”, “cell type”, “cofactor”, “effector”, “phenotype”, “pathology”, and “reference”. CCIs were manually retrieved from 272 studies published recently (less than six years ago). In the current version of CCIDB, 520 CCIs and their 38 context features have been manually collected and curated by biodata engineers. We suggest that CCIDB is a manually curated CCI resource that is highly useful, especially for analyzing context-dependent alterations in CCIs.