Proteomic Signature of Urosepsis: From Discovery in a Rabbit Model to Validation in Humans

Abstract

Urosepsis after upper urinary tract endoscopic lithotripsy (UUTEL) may cause uroseptic shock with high mortality, which can be prevented if early diagnosis and timely intervention are implemented with help of a diagnostic protein panel. The plasma of five rabbits of uroseptic shock and five controls was subjected to exploratory proteomics to search biomarker candidates from proteomic profiles related to uroseptic shock. Then, plasma from 21 nonsepsis and 20 urosepsis patients according to European diagnostic criteria of sepsis was enrolled in the validation study via targeted proteomics. Changes in a massive number of plasma proteins, mainly enriched in immune regulation, coagulation, structural repair, and transport activity, were observed in the rabbit model of septic shock. Fifteen proteins were identified as differential expression proteins between sepsis and nonsepsis patients. A diagnostic model composed of three proteins lipopolysaccharide-binding protein (LBP), clusterin (CLU), and vascular cell adhesion protein 1 (VCAM1) was developed for the early detection (2 hours postoperatively) of urosepsis after UUTEL, with a high area under the receiver operating characteristic (ROC) curve of 0.921. In conclusion, changes in the proteomic profile may reflect the underlying biological mechanisms during the development of urosepsis and produce diagnostic biomarkers for the early detection of urosepsis after UUTEL.

A novel model of urosepsis in rats developed by injection of Escherichia coli into the renal pelvis

“…However, widely applied and standardized animal models of urosepsis are relatively rare. Some scholars have found that rabbits can be used to develop models of urosepsis by injecting E. coli into the renal pelvis (13)(14)(15)(16). Rodents, the most widely used for experimental research, are rarely used to make models of urosepsis.…”

Pathways Associated with Positive Sepsis Survival Outcomes in African American/Black and Non-Hispanic White UTI Patients

“…Molecular changes associated with sepsis survival from patients with primary UTIs are not known. A prior proteomic study in UTI models and patients who developed sepsis proposed lipopolysaccharide-binding protein, clusterin, and VCAM1 as diagnostic markers of sepsis (52). Others have identified differentially expressed proteins involved in coagulation, the acute phase response, lipid homeostasis, and iron ion transport as associated with sepsis severity (53).…”

“…These changes are consistent with others’ reports of sepsis survival and disease severity of UTIs via discovery and targeted LC-MS/MS, enzyme-linked immunosorbent assays, real-time reverse transcription polymerase chain reaction, and western blotting (54–61). Similar to our previous analysis of patients with primary intra-abdominal infection, proteins related to inflammation and hepatic fibrosis/hepatic stellate cell activation were decreased in sepsis survivors (39), including VCAM1, which has also been proposed as a diagnostic biomarker for sepsis secondary to UTIs (52). Therefore, these pathways and related molecules may be key factors involved in sepsis survival across primary infection sources, especially soluble forms of proteins like VCAM1.…”

A novel model of urosepsis in mice developed by ureteral ligation and injection of Escherichia coli into the renal pelvis

“…Nevertheless, there exists a discernible scarcity of widely employed and standardized animal models pertaining to urosepsis. Certain scholars revealed that a urosepsis model can be established via intrarenal infusion of Escherichia coli into New Zealand rabbits' renal pelvis [ 8 , 9 ]. Recently, some scholars have attested to the efficacy of the Wistar rat model for urosepsis [ 10 ].…”

“…However, for New Zealand rabbits or Wistar rats, due to the absence of specific antibodies or transgenic animals, subsequent foundational mechanistic studies are impeded. Consequently, only physiological explorations can be conducted at present [ 9 ]. Given mice's widespread use as model organisms in experimental research, a standardized mouse model of urosepsis would facilitate swift exploration of urosepsis' pathophysiological mechanisms.…”