Establishment and clinical application of the HLA genotype database of platelet-apheresis donors in Suzhou.

The establishment of a platelet-apheresis donor database may provide a feasible solution to improve the efficacy of platelet transfusion in patients with immune platelet transfusion refractoriness (PTR). This study aimed to establish HLA genotype database in Suzhou, to provide HLA-I compatible platelets for PTR patients to ensure the safety and effectiveness of platelet transfusions. We used a polymerase chain reaction sequence-based typing (PCR-SBT) method to establish the database by performing high-resolution HLA-A, -B, and -C genotyping on 900 platelet-apheresis donors. HLA-I antibody was detected in patients using a Luminex device, and HLA-I gene matching was performed by an HLA-Matchmaker. We found that the highest frequency of the HLA-A allele was A*11:01 (17.06 %), followed by A*24:02 (14.67 %) and A*02:01 (13.61 %). The highest frequency of the HLA-B allele was B*46:01 (9.78 %), followed by B*40:01 (8.39 %) and B*13:02 (33 %). After the detection of platelet antibodies in 74 patients with immune PTR, we found 30 HLA-A antibodies and 48 HLA-B antibodies, and there were a variety of high frequency antibodies whose alleles were low in the donor database, such as HLA-A*68:02, and B*57:01. After avoiding donor-specific antibodies (DSA) matching, 102 of 209 platelet-compatible transfusions were effective, resulting in an effective rate of 48.8 %, which significantly improved the efficacy of platelet transfusion. The establishment of a platelet donor database is of great significance to improve the therapeutic effect of platelet transfusion in patients with hematologic disorder, and save blood resources, and it is also the premise and guarantee of precise platelet transfusion.

Role of variation in platelet indices in pregnancy-related pathological complications and the prediction of postpartum hemorrhage: a case-control study.

BACKGROUND: Pregnancy-related pathological complications (PPCs) increase the risk of postpartum hemorrhage (PPH), Platelet activation and destruction are expected outcomes of PPCs. This study sought to compare the platelet indices of non-pregnant (NP) child-bearing aged women, healthy pregnant (HP) women, and women with PPCs, and investigate the use of these indices in PPH prediction. METHODS: This retrospective clinical study included 260 NP child-bearing aged women and 119 pregnant women. Of the 119 pregnant patients, 69 had HPs and 50 suffered from PPCs. Further, 50 patients delivered with PPH. We compared the platelet counts (PCs), mean platelet volumes (MPVs), platelet distribution widths (PDWs), plateletcrits (Pcts), MPV ratios (PC/MPV and Pct/MPV), alpha angles (angles), and maximum amplitudes (MAs) of the patients using Sysmex XN10 hematology analyzer and TEG 5000 Hemostasis analyzer system, respectively. RESULTS: With the exception of PDW, there were significant differences in the platelet parameters of the NP, HP, and PPC patients (P<0.05). The intergroup comparison results showed that the NP patients differed significantly from the HP and PPC patients in terms of age, MA, PC, Pct, and Pct/MPV (P<0.0125). Further, the HP and PPC patients differed significantly in terms of Pct, MPV, PC/MPV, and Pct/MPV (P<0.0125). Additionally, the univariate analysis showed that in the PPC patients, low MPV values were strongly related to PPH [odds ratio (OR) =0.012, P=0.003; OR =0.331, P=0.047]. CONCLUSIONS: Women with PPCs had significantly lower PC, Pct, PC/MPV and Pct/MPV values, but significantly higher MA and MPV values. PPHs were strongly related to PPC and low MPV values. A timely accurate diagnosis and evaluating MPV values may be useful in the prediction of PPH.

[The Effect of Immunized Platelet Transfusion Refractoriness on Allo-HSCT Patients with Malignant Hematological Diseases].

OBJECTIVE: To investigate the characteristics of platelet antibody in patients with hematological diseases, so as to research the effect of immunized platelet transfusion refractoriness (PTR) on the prognosis of allogeneic hematopoietic stem cell transplantation (allo-HSCT) recepients with malignant hematological diseases patients. METHODS: The clinical data of platelet antibody positive patients tested by Capture-P in the First Affiliated Hospital of Soochow University from July 1, 2014 to July 1, 2019 were retrospectively analyzed, including sex, age, disease, platelet transfusion assessments, CD34+ cells, transplant prognosis, and so on. RESULTS: In 5 years, 913 (7.28%) hematologic patients with platelet antibody positive were identified, the detection rate of females (513 cases) were higher than males (400 cases). Among the 913 patients, the antibody positive rates of 520 patients with malignant hematological diseases (acute myeloid leukemia, acute lymphoblastic leukemia and myelodysplastic syndrome) showed significantly statistical different (10.27%, 8.01%, and 7.20%) (P<0.01), and the positive rate of the acute myeloid leukemia of those patients was higher than myelodysplastic syndrome patients(α<0.0125). There were 35 cases diagnosed as immunized PTR before allo-HSCT, the platelet increments, 14 h correct count increment, progression-free survival rate and overall survival rate of those patients were significantly lower than those in negative transfusion effective patients (P<0.01), while the percentage of ABO matching was significantly higher (α<0.0125). CONCLUSION: The positive rate of platelet antibody identification is high in females and acute myeloid leukemia patients, and immunized PTR caused by antibody is a risk factor for poor prognosis of allo-HSCT in malignant hematological disease patients.

[Preparation of a uncoordinated-5 homolog B monoclonal antibody and its effect on melanoma cell migration in vitro].

OBJECTIVE: To prepare and characterize the monoclonal antibody (mAb) against uncoordinated-5 homolog B (UNC5B) and analyze its effect on the migration of melanoma cells. METHODS: UNC5B gene fragment was cloned into the prokaryotic expression vector pET-32a. The recombinant UNC5B protein was expressed in E.coli BL21 (DE3) and purified by affinity chromatography. BALB/c mice were immunized with the recombinant protein and the hybridoma cell clones stably secreting UNC5B antibody were screened by traditional hybridoma technique. ELISA, Western blotting and flow cytometry were used to characterize the specificity of the antibodies. In addition, the effect of the mAb on melanoma cell migration was analyzed by wound healing assay. RESULTS: The recombinant UNC5B protein was expressed and purified. One high-titer antibody 2C9 was obtained. ELISA, Western blotting and flow cytometry all demonstrated that 2C9 antibody specifically recognized the UNC5B protein. Wound healing assay indicated that the UNC5B mAb could promote melanoma cell migration at the presence of netrin-1. CONCLUSION: A UNC5B-specific monoclonal antibody was prepared and proved to have the ability of promoting melanoma cell migration at the presence of netrin-1.

An uncoordinated-5 homolog B receptor monoclonal antibody regulates A375 melanoma cell migration.

Uncoordinated-5 homolog B receptor (UNC5B) was first found to mediate neural chemorepulsive effects by binding to its ligand netrin-1 in the nervous system. Newer evidence indicated that UNC5B also has functions outside the nervous system. In this study, we report on the generation of a monoclonal antibody specific to the outer-membrane immunoglobulin-like domains of UNC5B using the hybridoma technique. Western blot, immunofluorescence, and flow cytometry analyses showed that the antibody specifically bound to UNC5B protein. Interestingly, the antibody blocked the Netrin-1-induced inhibitory effect on the mobility of melanoma A375 cells by wound healing assay and transwell migration assay, whereas it had no effects on cell proliferation measured by CCK-8 assay. Thus, the functional antibody may provide a useful tool for the study of UNC5B expression profiles and functions outside the nervous system.

[Progress of study on interaction between platelets and endothelial cells].

Endothelial lesion is the most well known example for the interaction between platelets and endothelial cells, but the recent researches indicate that platelets and endothelial cells also participate in inflammation, tumor metastasis and lymphovascular development. Under these situations, the activated platelets express adhesive molecules and degranulate, and regulate the permeability, adhesion, survival, proliferation and metastasis of endothelial cells. All the achievements push the research on the interaction between platelets and endothelial cells to a new era, which would be more significant. In this review, the latest advances and prospect of the interaction between platelets and endothelial cells in inflammation, tumor and lymphovascular development are summarized.