The Role Of Plasma Secreted Protein Acid And Rich In Cysteine Like1 In The Diagnosis And Progression Of Sepsis

Background:Sepsis was defined as life-threatening organ dysfunction caused by the host’s dysregulated response to infection(Sepsis3.0)[1].Statistics show that there are about 49 million cases of sepsis worldwide each year,and 11 million of them die,almost a fifth of all global deaths from all causes.Therefore,sepsis is a major threat to human health[2-3].The clinical diagnostic criteria for sepsis is infection with organ dysfunction scores,which means that patients cannot be diagnosed as sepsis before they have organ dysfunctions.Therefore,the current diagnostic criteria have obvious hysteresis.In the absence of specific therapeutic drugs,the prognosis of patients with early diagnosis of sepsis is significantly better than that of other patients,so the study of early diagnosis methods is of great clinical significance.In view of this situation,the sepsis research field has conducted a lot of exploration on early diagnosis markers of sepsis,and examined the feasibility of over 200 biomarkers for the diagnosis of sepsis.However,most of these markers lack high sensitivity,specificity and accuracy,and are insufficient for the early diagnosis of sepsis.Previous studies have shown that infection-induced inflammation plays an important role in the pathogenesis of sepsis.SPARCL1,a member of the SPARC matricellular protein family,is expressed at high levels during development and in response to injury[4],has the effects of de-adhesion,anti-proliferation and easy migration[5].suggesting that SPARCL1 may not only affect wound healing,tumor growth,differentiation and prognosis,but also be involved in inflammatory response.In the previous study,we found by quantitative protein mass-spectrometry technique that the plasma level of SPARCL1 was significantly increased in sepsis patients who died within 24 hours,suggesting that the plasma level of SPARCL1 was related to the pathological process of sepsis.In this study,we explored the possibility of SPARCL1 as a marker for early diagnosis of sepsis.We collected plasma samples and relevant clinical examination data from normal people,patients with pneumonia and sepsis with pneumonia,then used ELISA to detect the level of SPARCL1 in plasma samples and its relationship with various clinical indicators and prognosis of sepsis patients.Plasma samples from patients with sepsis who were admitted to the RICU of the Huaihe Hospital of Henan University from June 2016 to July 2019 were selected as research objects,and a candidate sepsis-related protein,SPARCL1,was obtained by quantitative proteomic analysis.At the same time,plasma samples from community-acquired pneumonia patients and normal healthy people were collected.The collected sepsis patients were divided into two groups according to SOFA score: the sepsis-associated pneumonia group and the sepsis with pneumonia group.Plasma samples from different groups of patients were analyzed using ELISA technology to obtain plasma SPARCL1 levels in different study populations.The Wilcoxon / Mann-Whitney test was used to compare continuous variables among groups based on clinical data of patients.Spearman’s correlation coefficient for ranked data analysis was used to evaluate the correlation between SPARCL1 levels and clinical indicators.The patients were followed up for 28 days.Results:1 、 The average concentration of SPARCL1 in normal healthy human plasma is 7.48 ng / m L(4.69-8.70 ng / m L).2、The levels of SPARCL1 in the plasma of patients with community acquired pneumonia(8.78ng/ m L)were not significantly different from those of normal healthy people(p>0.05).3、The plasma SPARCL1 levels in patients with sepsis-associated pneumonia(11.09 ng / m L)were not significantly different from those in community-acquired pneumonia(p>0.05).4 、 The plasma SPARCL1 levels in patients with sepsis and pneumonia(22.13 ng / m L)were significantly higher than those in community-acquired pneumonia and sepsis-associated pneumonia(p<0.05).5、With the exacerbation of sepsis patients,SPARCL1 levels increased significantly(p<0.05).6、There is a correlation between plasma SPARCL1 levels and multiple organ failure in patients with sepsis.7、The AUC of the ROC curve of SPARCL1 in sepsis and 28-day mortality were 0.757 and 0.635,respectively.Conclusions:1、The Plasma SPARCL1 levels are helpful in determining the diagnosis and severity of sepsis;Methods:2、The Plasma SPARCL1 levels may have an impact on the prognosis of sepsis;3、Plasma SPARCL1 may play a role in septic organ damage,thereby affecting its mechanism of action during its development.4、Plasma SPARCL1 levels were measured in patients with suspected sepsis to assess the severity of their disease progression and the probability of their possible transition to sepsis.