Costimulator And Impaired Platelet Recovery In Pulmonary Infection Patients After Hematopoietic Stem Cell Transplantation

Part1:The effects of costimulator on Graft versus Host Disease after hematopoietic stem cell transplantationObjectiveAllogenetic hematopoietic stem cell transplantation(allo-HSCT) is an effective treatment for Leukemia.It is far superior to conventional chemotherapy in disease-free survival and overall survival improving in patients with leukemia,and is perhaps the only way to cure leukaemia,but it often accompanied by complications.About 20%of patients develop acute graft versus host disease(GVHD) after HSCT.GVHD is one of the main causes of transplant related mortality(TRM).When GVHD occurs,the donor T cell Receptor(TCR)is combined with the Antigen Peptide-major histocompatibility complex(MHC) Complex on target tissue antigen presenting cell(APC) to induce the first signal.At the same time,T cells combine with many co-stimulative molecules on APC to induce a second signal to activate donor T cells.The CD28 family,including CD28,inducible costimulator(ICOS),programmed cell death protein-1(PD-1) and cytotoxic T lymphocyte-associated antigen-4(CTLA-4),combined with its ligand CD80/86,ICOSL and PD-L1 to induce second signal thus activate donor T cells.This study established aGVHD mouse model to dynamically observe the changes of costimulating molecules,costimulating molecular ligands,and cytokines every week after transplantation,and analyzed the dynamic changes of costimulating molecules and aGVHD to investigate the reconstitution of bone marrow immuno-microenvironment during aGVHD.MethodsThe mice model of GVHD after hemopoietic stem cell transplantation was established.Peripheral blood was taken from mice weekly and co-stimulating molecules(ICOS,CD28,CTLA-4,PD-1) were detected by flow cytometry.The lymphocyte subsets in mice spleen(CD4+ T cells,CD8+ T cells,Th1 cells,Th2 cells,Th17 cells)were detected.The immunohistochemical method was used to detect co-stimulating molecular ligands(ICOSL,PD-L1,CD80).Results1?Mice in the aGVHD group gradually showed typical aGVHD performance such as arched back,depilation,and diarrhea 10 days after transplantation.The median time of the appearance of aGVHD was 14 days(11-18 days),and the median survival time was 22 days(13-30 days);The control group all survived within 30 days,and all of the aGVHD group developed.2?The ratio of CD8+ T cells in peripheral blood of the control group and aGVHD group increased rapidly in the first three weeks.After that,the GVHD group continued to maintain a rapid increase,but the BM group began to decline slowly from +21 days.There was no significant difference in the ratio of CD8~+ T cells in peripheral blood between the two groups after transplantation.After transplantation,the ratio of CD4~+/CD8~+ T cells in the peripheral blood of the two groups maintained a continuous downward trend after transplantation,and the GVHD group dropped rapidly.There was no significant difference between the two groups after transplantation.3.After transplantation,CD4~+ CTLA-4 in peripheral blood of GVHD group showed a rapid decline after transplantation,and fell to a minimum level after +28 days after transplantation,significantly lower than the control group(P=0.003);The overall level of CD4~+ CTLA-4 was lower in the GVHD group than in the control group after +14 days to +28 days of transplantation and there was no recovery trend until the end of observation(P=0.053).There was no significant difference between +7 days and +28 days after transplantation(P=0.120).CD8~+ CTLA-4 in peripheral blood of GVHD group showed a rapid decline after transplantation,and it was significantly lower than the level of control group(P=0.011) +28 days after transplantation,and the control group showed a rapid upward trend.The overall level of CD8+ CTLA-4 was significantly lower in the GVHD group than in the control group(P=0.006)from +14 days to +28 days.The expression of CD4~+ ICOS in peripheral blood of GVHD group after transplantation decreased slightly after transplantation,and was significantly higher than that of the control group(P=0.013)+28 days of transplantation.The control group showed a slow decline trend.There was no significant difference between the two groups(P=0.790);CD8~+ ICOS in peripheral blood in the GVHD group remained stable for +7-14 days after transplantation,then rose rapidly,reaching a peak at +21 days after transplantation and significantly higher than the control group level(P=0.001).The control group showed a slow downward trend and there was no significant difference between +7 days and +28 days after transplantation(P=0.058).After transplantation,CD4~+ PD-1 in peripheral blood of GVHD group was higher than the control group level at +7 days after transplantation(P=0.058);After transplantation,the expression level of the control group remained stable,and there was no significant difference between the two groups(P=0.734).CD8~+ PD-1 in peripheral blood in GVHD group was significantly higher than the control group(P=0.001) +7 days to +21 days after transplantation,and there was no significant difference between the two groups(P=0.060).There was no significant difference of CD4~+ CD28 in peripheral blood of two groups after transplantation(P=0.064).CD8~+ CD28 expressed no significant difference between the two groups(P=0.103).4.There was no positive expression of CD80 in intestinal gland epithelium in control group,and the positive expression rate of intestinal tissue in aGVHD group was 40%.There was no significant CD80 positive expression of liver cells in control group and aGVHD group.The spleen of control group mice showed negative expression.The positive rate of spleen tissue in aGVHD group was 60%.There was no significant positive expression of ICOSL in the control group,and partial positive expression of the intestinal tissue in the aGVHD group,with a positive expression rate of 80%(higher than CD80).There was no significant ICOSL positive expression in liver tissue in control group and aGVHD group.The lymphocytes of spleen tissue in BM group were not activated,and most of the lymphocytes in aGVHD group were brown and positive,with a positive rate of 90%.5.Compared with BM control group,the expression level of IL-17 and IFN-?was higher in aGVHD group,but IL-4 decreased(P<0.05).ConclusionWhen GVHD occurs,the ratio of CD4~+/CD8~+ T cells decreased,the expression of positive costimulating molecules CD28 and ICOS was promoted,the expression of negative costimulating molecules CTLA-4 and PD-1 was inhibited,and the differentiation of T-assisted cell was activated to Th1,thus GVHD further develops.Part2: Impaired platelet recovery in pulmonary infection patients after allogeneic hematopoietic stem cell transplantation: a propensity score-matched analysisObjective It is generally believed that platelets produced mainly by bone marrow,but studies had indicated that part of platelet formation takes place in the lungs as early as in 1936.When lung injury happens,megakaryocytes from lungs reduce,and result in significant reduction of platelets in the circulation.Pulmonary infection is one of the life-threatening complications after allogeneic hematopoietic stem cell transplantation(allo HSCT)even when the prophylactic measures have been employed.But few studies investigated whether and how pulmonary infection affects platelet recovery during allo HSCT procedure.We designed a propensity score-matched analysis compared the recovery of platelet in patients with or without pulmonary infection after allo HSCT.Methods We retrospectively reviewed 181 consecutive patients with hematologic diseases who received allo HSCT in our institute.Among them,32 patients were with pulmonary infection within 3 months after allo HSCT.For these 32 patients,64 patients without pulmonary infection were selected using the one-to-two propensity score matching logistic model based on age(< 20 y,20 to 40 y,41 to 60 y or > 60 y),disease and stage,days from diagnosis to transplantation,median CD34+ cells and mononuclear cells.The impact of pulmonary infection on platelet recovery was analyzed,and the clinical outcomes between the two groups were compared.Results The average time for platelet recovery in patients with and without pulmonary infection were 16.07days(range,11 to 49 days)and 12.89 days(range,8 to 20 days,P=0.001),respectively.Univariable logistic regression showed that impaired platelet recovery was significantly associated with pulmonary infection(P=0.001),non-malignant hematological diseases(P=0.023),conditioning regimen without fludarabine(P=0.003),and HLA-mismatched allo HSCT(P=0.005).Multivariable logistic regression showed that impaired platelet recovery was significantly associated with pulmonary infection(P=0.001),conditioning regimen without fludarabine(P=0.001),HLA-mismatched allo HSCT(P=0.013).Impaired platelet recovery did not have an impact on disease-free survival(DFS)[31 months(range,3 to 50 months)and 20 months(range,1 to 56 months),respectively,P=0.709] and overall survival(OS)[19 months(range,3 to 50 months)and 21 months(range,1 to 56 months),respectively,P= 0.399].Conclusions With propensity match testing,the incidence of impaired platelet recovery in patients with pulmonary infection was markedly higher than that in the matched-control group of patients without pulmonary infection.Pulmonary infection after allo HSCT has a negative effect on platelet recovery.