Diagnostic and prognostic roles of soluble CD22 in patients with Gram-negative bacterial sepsis

BACKGROUND： Soluble CD22（sCD22） is a fragment of CD22, a B cell-specific membrane protein that negatively regulates B-cell receptor signaling. To date, sCD22 has only been regarded as a tumor marker of B-cell malignancies. Its expression in infectious diseases has not yet been assessed.METHODS： Serum concentrations of sCD22, procalcitonin（PCT） and interleukin-6（IL-6） were measured by enzymelinked immunosorbent assays in patients with intra-abdominal Gram-negative bacterial infection. Receiver operating characteristic curve analysis was performed to evaluate the diagnostic accuracy of these biomarkers in this type of infection. The correlations between biomarkers and the Acute Physiology and Chronic Health Evaluation（APACHE） II scores were also analyzed.RESULTS： Concentrations of sCD22 were significantly elevated in patients with sepsis and the elevation is correlated with the severity of sepsis. sCD22 was also slightly elevated in patients with non-infected systemic inflammatory response syndrome or local infection. The diagnostic accuracy of sCD22 for sepsis was equivalent to that of PCT or IL-6. In addition, the correlation of sCD22 with APACHE II scores was stronger than that of PCT or IL-6.CONCLUSIONS： Serum sCD22 is a novel inflammatory mediator released during infection. This soluble biomarker plays a potential role in the diagnosis of Gram-negative bacterial sepsis, with a diagnostic accuracy as efficient as that of PCT or IL-6. Furthermore, sCD22 is more valuable to predict the outcomes in patients with sepsis than PCT or IL-6. The present study suggested that sCD22 might be potentially useful in supplementing current criteria for sepsis.

Relationship of Transforming Growth Factor-β1 and Arginase-1 Levels with Long-term Survival after Kidney Transplantation

In this study, we compared the serum levels of transforming growth factor-β1 （TGF-β1）, interleukin-10 （IL-10）, and arginase-1 in long-term survival kidney transplant recipients （LTSKTRs） with those in short-term survival kidney transplant recipients （STSKTRs）. We then evaluated the relationship between these levels and graft function. Blood samples were collected from 50 adult LTSKTRs and 20 STSKTRs （graft survival approximately 1-3 years post-transplantation）. All patients had stable kidney function. The samples were collected at our institution during the patients＇ follow-up examinations between March 2017 and September 2017. The plasma levels of TGF-β1, IL- 10, and arginase- 1 were analyzed using enzyme-linked immunosorbent assays （ELISA）. The levels of TGF-β1 and arginase-1 were significantly higher in the LTSKTRs than in the STSKTRs. The time elapsed since transplantation was positively correlated with the levels of TGF-β1 and arginase-1 in the LTSKTRs. The estimated glomerular filtration rate was positively correlated with the TGF-β1 level, and the serum creatinine level was negatively correlated with the TGF-β1 level. Higher serum levels of TGF-β1 and arginase-1 were found in LTSKTRs than in STSKTRs, and we found that TGF-β1 was positively correlated with long-term graft survival and function. Additionally, TGF-β1 and arginase-1 levels were positively correlated with the time elapsed since transplantation. On the basis of these findings, TGF-β1 and arginase- 1 may play important roles in determining long-term graft survival. Thus, we propose that TGF-β1 and arginase-1 may potentially be used as predictive markers for evaluating long-term graft survival.