You will be shown an abstract from a biomedical research paper. Given this abstract, your task is to extract all unique entities of the following types: ["RNA", "CellLine", "Protein", "DNA", "CellType"].

Please return the output as a JSON object of the format: {"DNA" : ["TAL1", ...], "RNA": ["mRNAs", ...], "CellLine": ["T cells", ...], "CellType": ["monocytes", ...], "Protein": ["IL-2", ...]}. The keys should be entity types and values should be lists of extracted entities belonging to the corresponding type. If you cannot find entities belonging to a specific type, the value should be [].

Only output the JSON object and do not include any additional text.

Abstract:

Interleukin 6-induced differentiation of a human B cell line into IgM-secreting plasma cells is mediated by c-fos. The role of the protooncogene c-fos in interleukin (IL) 6-induced B cell differentiation was assessed. Treatment of SKW 6. 4 cells with IL 6 induced a transient and early stimulation of c-fos sense mRNA expression. The effect appeared within 30 min and returned to basal levels after 2 h. The addition of antisense oligonucleotides to c-fos significantly inhibited IL 6-induced IgM production by SKW 6. 4 cells (p less than 0. 001), whereas control oligonucleotides had no inhibitory effect. These results indicate that activation of c-fos is involved in IL 6-induced differentiation of SKW 6. 4 cells into IgM-secreting cells.
{"CellLine": ["IgM - secreting cells", "human B cell line", "SKW 6 . 4 cells"], "CellType": ["IgM - secreting plasma cells", "IgM - secreting cells"], "DNA": ["protooncogene c - fos", "c - fos", "the protooncogene c - fos"], "Protein": ["interleukin (IL) 6", "IgM", "IL 6"], "RNA": ["c - fos sense mRNA"]}