Lymphocyte Subsets Can Indicate The Risk Of Early Infection After Liver Transplantation

Objective:Liver allotransplantation has become an effective method for the treatment of various end-stage liver diseases.But infection complications remain a major challenge for liver transplant patients and clinicians.We investigate the relationship between the peripheral blood lymphocyte subsets,including the percentage and absolute count,and early infection after liver transplantation.We also investigate the correlation between tacrolimus concentration and absolute CD4~+T cell count.To identify clinical indicators suitable for assessing the risk of infection in patients after liver transplantation.Methods:Peripheral blood was collected from patients who underwent liver transplantation in the Affiliated Hospital of Qingdao University from April 2019 to August 2019.According to whether the patients were infected during clinical sample collection,97 subtotal blood samples were divided into a noninfected group(n=76)and an infected group(n=21).Infection is mainly diagnosed by clinical symptoms,blood changes,imaging results(chest CT,etc.),and microbiological examination results of blood,sputum and various drainage fluids.The percentages and absolute counts of CD3~+T cells,CD4~+T cells,CD8~+T cells,CD19~+B cells,CD3~-CD56~+NK cells and CD3~+ CD25~+T cells were detected and calculated using fluorescently labeled monoclonal antibodies and flow cytometry,respectively.The CD4~+/CD8~+ratio was also calculated.Chemiluminescence was used to determine tacrolimus concentration in whole blood of patients after liver transplantation.SPSS 21.0 software was used for statistical processing of the data.The t test of two independent samples was used for inter-group comparison.The correlation between tacrolimus concentration and absolute CD4~+T cell count was analyzed by Pearson correlation.Results:The concentration of tacrolimus in the non-infected group was slightly lower than that in the infected group,but there was no statistically significant difference between the two groups(P>0.05).According to Pearson correlation analysis,there was no significant correlation between absolute CD4~+T cell count and tacrolimus concentration in patients after liver transplantation(P>0.05).In terms of the percentage of lymphocyte subsets,CD3~+T cells(t=4.314,P<0.01),CD4~+T cells(t=2.549,P<0.05)and CD8~+T cells(t=2.258,P<0.05)in the non-infected group were higher than those in the infected group,while CD19~+B cells(t=-3.312,P<0.01)were lower in the non-infected group than in the infected group.There were no significant differences in the CD4~+/CD8~+ratio,CD3~-CD56~+NK cells and CD3~+CD25~+T cells between the two groups(P>0.05).In terms of the absolute count of lymphocyte subsets,CD3~+T cells(t=12.037,P<0.01),CD4~+T cells(t=11.134,P<0.01),CD8~+T cells(t=8.516,P<0.01),CD3~-CD56~+NK cells(t=2.215,P<0.05)and CD3~+CD25~+T cells(t=6.889,P<0.01)in the non-infected group were all higher than those in the infected group.However,the difference in CD19~+B cells between the two groups was not statistically significant(P>0.05).Conclusion:Monitoring tacrolimus concentrations in liver transplant patients does not reflect the extent to which tacrolimus inhibits CD4~+T cells,nor does it assess the risk of infection in patients early after liver transplantation.The percentage and absolute counts of T lymphocyte subsets are important for assessing the risk of early infection after liver transplantation.Monitoring the absolute count of CD3~-CD56~+NK cells helps to assess the risk of early infection after liver transplantation.