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:

Costimulation of cAMP and protein kinase C pathways inhibits the CD3-dependent T cell activation and leads to a persistent expression of the AP-1 transcription factor. The effects mediated by a combined stimulation of cAMP-and protein kinase C (PKC) -dependent pathways have been investigated in different cellular systems, and it has been shown that they may complement each other in activating cell proliferation and differentiation. In this report, we show that upon the stimulation of both pathways T lymphocytes became refractory to activation via the CD3 / T cell receptor (TcR) complex. T cells preincubated with phorbol 12-myristate 13-acetate (PMA) and dibutyryl cAMP (Bt2cAMP) displayed a deficient proliferative ability in response to anti-CD3 mAb stimulation, whereas lymphocytes treated individually with either Bt2cAMP or PMA responded comparably to untreated samples. We detected an association between the reduced mitogenic response and low expression of both interleukin-2 (IL-2) and the alpha chain (CD25) of the IL-2 receptor (IL-2R). Analysis of intracellular Ca2 + mobilization suggested that the CD3 / TcR-dependent signal transduction was impaired in PMA / Bt2cAMP-treated cells. Remarkably, we observed that these samples displayed a persistent expression of the c-fos protooncogene, associated to an increased AP-1 DNA-binding activity, whereas no variations of CREB or NF-kB were detected. Neither Bt2cAMP nor PMA individually mediated these sustained effects, which therefore appear as a consequence of the interplay between both metabolic stimuli. Altogether, the data provide the evidence that both pathways complement each other in regulating gene expression and, conversely, downregulate the TcR transduction mechanisms.
{"CellLine": ["PMA / Bt2cAMP - treated cells"], "CellType": ["T lymphocytes", "lymphocytes", "T cells"], "DNA": ["c - fos protooncogene"], "Protein": ["NF - kB", "IL - 2 receptor", "CD25", "PKC", "TcR", "CREB", "interleukin - 2", "AP - 1 transcription factor", "CD3 / T cell receptor", "AP - 1", "CD3", "anti - CD3 mAb", "protein kinase C", "IL - 2", "alpha chain", "IL - 2R"], "RNA": []}