CCL2 and sarcoidosis: It seems that this group of chemokines, and especially MCP-1 (CCL2) whose levels increase significantly in malignant pleural effusions [16, 43–46], plays an important role in inflammatory lung diseases such as asthma, sarcoidosis, pulmonary fibrosis, but also in tuberculosis, pleural effusions, pneumonia, acute espiratory distress syndrome (ARDS) and tumors development [42, 47–49].