Pancreatic ductal adenocarcinoma (PDAC) is a highly lethal malignancy. PDAC is only cured by surgical resection in its early stage, but there remains a relatively high possibility of recurrence. The development of PDAC is closely associated with the tumor microenvironment. Tumor-associated macrophages (TAMs) are one of the most abundant immune cell populations in the pancreatic tumor stroma. TAMs are inclined to M2 deviation in the tumor microenvironment, which promotes and supports tumor behaviors, including tumorigenesis, immune escape, metastasis, and chemotherapeutic resistance. Herein, we comprehensively reviewed the latest researches on the origin, polarization, functions, and reprogramming of TAMs in PDAC.

Background: At the end of 2019, a novel coronavirus outbreak emerged in Wuhan, China, and its causative organism has been subsequently designated the 2019 novel coronavirus (2019-nCoV). The effectiveness of adjunctive glucocorticoid therapy in the management of 2019-nCoV-infected patients with severe lower respiratory tract infections is not clear, and warrants further investigation. Methods: The present study will be conducted as an open-labeled, randomized, controlled trial. We will enrol 48 subjects from Chongqing Public Health Medical Center. Each eligible subject will be assigned to an intervention group (methylprednisolone via intravenous injection at a dose of 1-2 mg/kg/day for 3 days) or a control group (no glucocorticoid use) randomly, at a 1:1 ratio. Subjects in both groups will be invited for 28 days of follow-up which will be scheduled at four consecutive visit points. We will use the clinical improvement rate as our primary endpoint. Secondary endpoints include the timing of clinical improvement after intervention, duration of mechanical ventilation, duration of hospitalization, overall incidence of adverse events, as well as rate of adverse events at each visit, and mortality at 2 and 4 weeks. Discussion: The present coronavirus outbreak is the third serious global coronavirus outbreak in the past two decades. Oral and parenteral glucocorticoids have been used in the management of severe respiratory symptoms in coronavirus-infected patients in the past. However, there remains no definitive evidence in the literature for or against the utilization of systemic glucocorticoids in seriously ill patients with coronavirus-related severe respiratory disease, or indeed in other types of severe respiratory disease. In this study, we hope to discover evidence either supporting or opposing the systemic therapeutic administration of glucocorticoids in patients with severe coronavirus disease 2019. Trial registration: ClinicalTrials.gov, ChiCTR2000029386, http://www.chictr.org.cn/showproj.aspx?proj=48777.

The glycoprotein CD58, also known as lymphocyte-function antigen 3 (LFA-3), is a costimulatory receptor distributed on a broad range of human tissue cells. Its natural ligand CD2 is primarily expressed on the surface of T/NK cells. The CD2-CD58 interaction is an important component of the immunological synapse (IS) that induces activation and proliferation of T/NK cells and triggers a series of intracellular signaling in T/NK cells and target cells, respectively, in addition to promoting cell adhesion and recognition. Furthermore, a soluble form of CD58 (sCD58) is also present in cellular supernatant in vitro and in local tissues in vivo. The sCD58 is involved in T/NK cell-mediated immune responses as an immunosuppressive factor by affecting CD2-CD58 interaction. Altered accumulation of sCD58 may lead to immunosuppression of T/NK cells in the tumor microenvironment, allowing sCD58 as a novel immunotherapeutic target. Recently, the crucial roles of costimulatory molecule CD58 in immunomodulation seem to be reattracting the interests of investigators. In particular, the CD2-CD58 interaction is involved in the regulation of antiviral responses, inflammatory responses in autoimmune diseases, immune rejection of transplantation, and immune evasion of tumor cells. In this review, we provide a comprehensive summary of CD58 immunobiology.