CCL4 and COVID-19: The molecular signature analysis of bronchoalveolar lavage fluid reveals that COVID-19 patients overexpress neutrophil recruiting mediators (CXCL1, CXCL2, CCL2, CCL7, and CXCL8) and the attractants of mainly innate immune cells (CCL2, CCL3, CCL4, CCL7, CCL8, CCL20, CXCL6, and CXCL11), resulting in COVID-19 a pulmonary centric disease27.