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Background The efficacy of hetrombopag in Chinese patients with immune thrombocytopenia (ITP) has been demonstrated in a randomized, double-blind, placebo-controlled, multicenter, phase III trial (NCT03222843). Objective This study aimed to report comprehensive data on a ≤6-week dose tapering to withdrawal (Stage 3) and an additional 24-week long-term extension period (Stage 4) in this phase III trial. Patients/methods Patients who fulfilled the screening criteria were eligible to enter Stage 3 or 4. During Stage 3, hetrombopag was gradually tapered to withdrawal. During Stage 4, hetrombopag treatment was initiated at 2.5, 3.75, 5, or 7.5 mg once daily. The efficacy endpoints during Stage 3 or 4 and the safety profile during the entire treatment period were reported. Results Among 194 patients who entered Stage 3, 171 (88.1%) relapsed. The median time to the first relapse since the start of Stage 3 was 15.0 days (95% CI, 14.0-16.0). In Stage 4, 144 (42.5%) patients responded at ≥75% of their assessments and 254 (74.9%) patients achieved platelet count ≥30×109 /L at least once, which was at least twice their baseline platelet count in the hetrombopag group (n=339). The most common adverse events were upper respiratory tract infection (53.1%), thrombocytopenia (27.1%), and urinary tract infection (21.2%) in the hetrombopag group. Conclusion The majority of patients who experienced dose tapering to withdrawal experienced a relapse. Long-term treatment with hetrombopag was effective in increasing and maintaining platelet count within the desired range in Chinese adults with ITP. Hetrombopag was well tolerated.

Although long non-coding RNA (lncRNA) HCP plays essential roles in human cancers, its function and mechanism in multiple myeloma (MM) have not crystallized. HCP5 level in MM was assessed through qRT-PCR. A series of functional investigations were conducted to evaluate the influences of HCP5 on proliferation and apoptosis. Bioinformatics analysis and RIP/RNA pull-down assays were carried out to determine the relationships among HCP5, miR-128-3p, and PLAGL2. Relative protein level was determined through Western blot. A xenograft tumor model was applied for validating the roles of HCP5/miR-128-3p/PLAGL2 axis in vivo. HCP5 was significantly increased in MM. HCP5 knockdown effectively thwarted the proliferative rate and cell cycle of MM cell lines and suppressed tumor growth. HCP5 regulated PLAGL2 expression by sponging miR-128-3p. PLAGL2 overexpression effectively rescued cells from influences by sh-HCP5 on cell proliferative and apoptotic rates. Additionally, HCP5 knockdown significantly inhibited Wnt/β-catenin/cyclin D1 signaling, and these effects were eliminated by PLAGL2 overexpression. Our study revealed that HCP5/miR-128-3p/PLAGL2 is closely correlated to MM development by modulating Wnt/β-catenin/cyclin D1 signaling. HCP5 promoted cell proliferation and tumor formation of MM cells by activating the Wnt/β‐catenin/CCND1 signaling pathway by sponging miR-128-3p to increase PLAGL2 expression

Myelofibrosis (MF) is associated with several constitutional symptoms. Currently, there are few therapeutic options for MF. Jaktinib, a novel, small-molecule inhibitor of JAK, is currently being studied for its potential to treat MF. This phase 2 trial investigated efficacy and safety of jaktinib in the treatment of MF patients. The primary end point was the proportion of patients with ≥35% reduction in spleen volume (SVR35, proportion of patients with ≥35% reduction in spleen volume) at week 24. The secondary end points included improvement of anemia, rates of symptom response, and safety profile. Between January 8, 2019 and August 29, 2020, 118 patients were recruited and treated with either jaktinib 100 mg BID or 200 mg QD. At week 24, 54.8% (34/62) of patients in the 100 mg BID group and 31.3% (15/48) in the 200 mg QD group achieved SVR35 (p = .0199). Jaktinib treatment increased hemoglobin level to ≥20 g/L in 35.6% (21/59) of patients with hemoglobin ≤100 g/L at baseline. The proportion of patients who achieved a ≥50% improvement in total symptom score at week 24 was 69.6% (39/56) in the BID group and 57.5% (23/40) in the QD group. The most common ≥ grade 3 hematological treatment-emergent adverse events (TEAEs; ≥ 10%) were anemia (100 mg BID: 24.2%, 200 mg QD: 28.8%), thrombocytopenia (16.7%, 11.5%), and neutropenia (3.0%, 11.5%). All non-hematological TEAEs were mild. These results indicate that jaktinib can shrink the spleen, improve anemia, and other clinical symptoms with good tolerability.

Introduction Skp2 is an E3 ubiquitin ligase that plays an important role in modulating tumor progression. The mechanisms underlying Skp2 in the promotion of proliferation and its function in the primary resistance to tyrosine kinase inhibitors (TKIs) in human CML remain to be determined. This study aimed to investigate the function of Skp2 in CML progression as well as its effects on TKI sensitivity. Methods Expression of Skp2 in leukocytes from patients with CML and normal blood samples was analyzed by qRT-PCR. Cell proliferation was analyzed by EdU incorporation and cell counting assays. Luciferase reporter and chromatin immunoprecipitation assays were used for examination of the effects of CREB on Skp2 expression. The apoptosis in vitro of K562 cells was analyzed by MTT and caspase 3/7 activity assays. Results The present study demonstrates that Skp2 was expressed at a higher level in patients with CML compared with healthy donors, and the elevated expression of Skp2 is critical for CML cell proliferation. Mechanistically, Skp2 was transcriptionally upregulated by CREB responsive to the PI3K/Akt signaling pathway. Furthermore, inhibition of Skp2 expression by shRNAs or blocking the PI3K/Akt/CREB pathway greatly enhances the sensitivity of CML cells to Imatinib treatment. Conclusion We conclude that the PI3K/Akt/CREB axis regulates the sensitivity of K562 cells to Imatinib via mediating Skp2 expression. The present study revealed an unknown role of Skp2 in CML progression and provided new aspects on the Skp2-modulated TKI sensitivity in CML, contributing to the development of potential therapeutic anticancer drugs.

This study is to assess the clinical value of in vitro primary cell high-efficiency expansion and high-throughput drug sensitivity screening (HEHDS) system in leukemia, and we evaluated a cohort of 121 patients with acute myeloid leukemia (AML) and 27 patients with acute lymphoblastic leukemia (ALL) using HEHDS. Bone marrow aspirates were collected from patients with leukemia. Purified leukemic cancer cells were obtained, cultured, and screened with a panel of 247 FDA-approved compounds by HEHDS technology. Ninety-six patients received HEHDS-guided therapy while 52 patients who were subjected to physician directed therapy served as controls. ALL patients who received treatment guided by HEHDS showed higher rate of complete remission (CR) than that of patients in the non-HEHDS group (90.91% vs. 56.25%). Similarly, AML patients received HEHDS-guided therapy were found to have greater CR rate, when compared with patients who received physician-directed therapy (45.88% vs. 25%). There was a significantly higher rate of CR in HEHDS-guided therapy group compared to the non-HEHDS group. The application of HEHDS could be beneficial for leukemia treatment.

KIF2A has been shown to be involved in the regulation of AML pathology, however, the mechanistic role of KIF2A in AML has not been fully identified. The present study aimed to identify the underlying mechanism of KIF2A regulation of AML cell function and chemosensitivity. A total of 58 patients with AML and 30 healthy subjects were enrolled for clinical analysis. AML cells (KG‑1 and Kasumi‑1) were transfected with KIF2A or control small interfering (si)RNA. PI3K/AKT pathway activator (740 Y‑P) and RhoA overexpression plasmid were added to rescue the effect of KIF2A siRNA. Cell proliferation, apoptosis, chemosensitivity to ADR and AraC, expression levels of mRNA/proteins associated with PI3K/AKT and RhoA/ROCK pathways were measured by Cell Counting Kit‑8, flow cytometry, reverse transcription‑quantitative PCR and western blotting. KIF2A was overexpressed, and correlated with higher levels of bone marrow blast, poor risk classification, lower treatment response and unfavorable survival profile in patients with AML. KIF2A siRNA inhibited proliferation but enhanced apoptosis and chemosensitivity to ADR and AraC in KG‑1 and Kasumi‑1 cells, which also inactivated PI3K/AKT and RhoA/ROCK pathways. Subsequent rescue experiments showed that 740 Y‑P and RhoA overexpression plasmid promoted cell survival and decreased chemosensitivity, which reversed the effect of KIF2A siRNA in KG‑1 and Kasumi‑1 cells. KIF2A was correlated with worse clinical features and survival in patients with AML; its knockdown promoted apoptosis and chemosensitivity by inactivating PI3K/AKT and RhoA/ROCK signaling pathways in AML cells. These data suggested KIF2A may be a potential prognostic marker and treatment target for AML management.

Additional file 1: Table S1. Investigators per site. Table S2. Dose adjustments of hetrombopag during the double-blind treatment period and open-label treatment period. Table S3. Dose adjustments of eltrombopag for patients in the Placebo-eltrombopag group during the double-blind treatment period and open-label treatment period. Table S4. Platelet responses (platelet counts ≥ 50 × 109/L at week 8) were observed across all subgroups of baseline platelet counts, sex, age, and splenectomy status. Table S5. Proportion of responders at different time points within 8 weeks after treatment.

Leukemia accounts for a significant mortality across the globe every year. The main objective of the present research work was directed towards studying the anticancer effects of scutellarin-a plant flavone, against K562 human leukemia cells, along with examining its effects on cellular apoptosis, cell cycle, cell migration and cell invasion as well as Raf/MEK/ERK signalling pathway.Cell viability of K562 leukemia cells was evaluated by WTS-1 assay, while apoptotic effects induced by scutellarin in K562 cells were examined by fluorescence microscopy, flow cytometry, and western blot methods. Effects on cell cycle were measured by flow cytometry. Transwell Matrigel assay was performed to evaluate whether scutellarin induces inhibition of cell migration and cell invasion effects in K562 cells.Scutellarin was shown to suppress the viability of the K562 cells dose-dependently with an IC50 of 6 μM. Further, scutellarin was shown to induce apoptosis which was initially exhibited by DAPI and annexin-V/propidium iodide (PI) staining and then confirmed by western blot in which it was shown to trigger regulation of Bax and downregulation of Bcl-2 in K562 human leukemia cells. Scutellarin also induced G0/G1 cell cycle arrest which was accompanied by suppression of cell migration and invasion. Scutellarin also led to the decline of the expression of p-Raf, p-MEK1/2 and p-ERK1/2 in a concentration-dependent manner.In conclusion, scutellarin could inhibit the growth of K562 human leukemia cells by inducing apoptosis, cell cycle arrest, inhibition of cell migration and invasion and downregulating the expressions of p-Raf, p-MEK1/2 and p-ERK1/2.

As a two dimensional material with extraordinary optoelectronic properties, graphene has been persistently focused and studied. Inspired by the effects of prominent near-field enhancement and tight field confinement of graphene surface plasmons, tunable perfect absorber constituted by square graphene-dielectric arrays is proposed in this work and investigated with numerical simulation. Complete monolayer graphene is utilized in the arrays, without demand of manufacture process to cut graphene layer into periodic patterns. Within a wide range of specific geometric parameters, the arrays achieve two absorption peaks with near unity absorbance at near-infrared wavelengths. The absorption performance of the arrays is also independent of polarization. It's discovered that surface plasmonic modes are simultaneously excited on graphene and gold-dielectric interface, and there is a strong coupling between such two modes. Moreover, both of the two peaks can be dynamically tuned by adjusting chemical potential of graphene, without salient absorption reduction. With these excellent features, the arrays may provide prospects in development of new sensors and switches. Keywords: Graphene, Surface plasmons, Perfect absorption, Tunable absorption

Cutaneous T-cell lymphoma (CTCL) is associated with the downregulation of miR-337 expression, although the exact underlying mechanism is unknown. In the present work, we investigated the molecular mechanism and function of miR-337 in regulating CTCL cell viability and invasion. We observed that miR-337 expression was downregulated in both CTCL tumors and cell lines. Furthermore, CCK assay, BrdU incorporation assay, and flow cytometry revealed that transfection with the miR-337 mimic resulted in decreased proliferation and increased apoptotic levels in CTCL cells. Results of the Transwell migration assay indicated that the miR-337 mimic decreased CTCL cell invasion in vitro. Both bioinformatics prediction and the dual-luciferase reporter assay revealed that miR-337 targets the 3'-UTR of STAT3 for silencing. Overexpression of STAT3 counteracted the pro-apoptotic influence of miR-337 in CTCL cell lines and restored their invasion properties. The results thus indicate that the miR-337-STAT3 axis inhibits the proliferation of malignant T cells and that miR-337 may serve as a promising therapeutic target for CTCL.

BCR fused ABL kinase is the critical driving oncogene for chronic myeloid leukemia (CML) and has been extensively studied as the drug discovery target in the past decade. The successful introduction of tyrosine kinase inhibitors (TKI) such as Imatinib, Dasatinib and Bosutinib has greatly improved the CML patient survival rate. However, upon the chronic treatment, a variety of TKI resistant mutants, such as the V299L mutant which has been found in more and more patients with the high-throughput sequencing technology, are observed, although the incidence is still considered rare compared to the more prevalent gatekeeper T315I mutant. However, with the progress of the precision medicine concept, the rare mutation (or the orphan drug target) has attracted more and more attention. Here we report a novel type II BCR-ABL kinase inhibitor, CHMFL-ABL-039, which not only displayed great potency (IC(50): 7.9 nM) and selectivity (S score (1) = 0.02) against native ABL kinase among other kinases in the kinome, but also exhibited great potency (IC(50): 27.9 nM) and selectivity against Imatinib-resistant V299L mutant among other frequently observed ABL kinase mutants. CHMFL-ABL-039 has demonstrated greater efficacies than Imatinib regarding to the anti-proliferation, inhibition of the signaling pathway, arrest of cell cycle progression, induction of apoptosis in vitro and suppression of the tumor progression in vivo in the native and V299L mutated BCR-ABL kinase-driven cells/xenograft models. It would be a useful pharmacological tool to study the TKI resistant ABL V299L mutant-mediated pathology and provide a potential precise treatment approach for this orphan CML subtype in the precision medicine era.

The Snail family transcriptional repressor 1 gene (Snail1) was screened in multiple myeloma cells (MMCs) from bortezomib-resistant MM patients and was found to be significantly associated with the development of drug-resistance mechanisms. In the present study, we first confirmed that the protein expression of Snail1 in bortezomib-resistant MMCs was significantly higher than that in MMCs without bortezomib resistance. The mechanistic studies confirmed that the enhancement of Snail1 expression in bortezomib-resistant MMCs directly upregulated transcription of the intracellular MDR1 gene to immediately develop multiple drug resistance mechanisms and inhibited P53 protein expression through the Snail1/hsa-miRNA-22-3p/P53 pathway to inhibit tumor cell apoptosis. By upregulating MDR1 and downregulating P53, Snail1 induced the drug resistance of MMCs to bortezomib, while Snail1 gene silencing effectively improved the drug sensitivity of MMCs to bortezomib chemotherapy. The present study further elucidated the drug resistance mechanisms of MMCs and provides evidence for increased clinical efficacy of bortezomib in MM patients.

Objective: We aimed to investigate the expression of interleukin 12 (IL-12) family cytokines (IL-12, IL-23, IL-27 and IL-35) and their relevant cytokines (IFN-γ, IL-4, IL-17A and IL-10) in patients with chronic immune thrombocytopenia (cITP) as well as the effect of high-dose dexamethasone (HD-DXM) treatment on this expression. Materials and Methods: DXM was administered orally at a dose of 40 mg per day for 4 consecutive days to 38 patients with cITP. We measured the plasma levels of IL-12p70, IL-23, IL-27, IFN-γ, IL-4 and IL-17A before and after treatment and also in 36 matched healthy controls, by means of FlowCytomix™ technology. The plasma levels of IL-10 and IL-35 were measured by enzyme-linked immunosorbent assay. Results: Significantly higher plasma levels of IL-12p70, IL-23, IL-27, IFN-γ and IL-17A were observed in cITP patients than in controls (p < 0.01), and after HD-DXM treatment, these levels decreased significantly (p < 0.01). However, significantly lower plasma levels of IL-4, IL-10 and IL-35 were observed in cITP patients than in controls (p < 0.01); after the HD-DXM treatment, these levels had increased significantly in the cITP patients (p < 0.01). Moreover, the cytokine levels of patients who attained a complete response returned to the levels of normal controls (p > 0.05) but were not corrected in the patients who had no response (p < 0.01). Conclusions: The patients with cITP had abnormal expression of the IL-12 family cytokines and their relevant cytokines levels, and HD-DXM treatment corrected the derangement of plasma cytokines. Measuring cytokine levels may help in the clinical assessment of cITP.

Chronic immune thrombocytopenia (cITP) is an autoimmune disease with disturbed cytokine profile. Although plasma levels of IL-27 are shown to be associated with cITP, its association with T cell subsets has not been studied. The objective of this study was to study the association between IL-27 and different T cell subsets in patients with cITP. Heparinized blood was collected from 31 patients with cITP and 36 healthy controls (platelet count

In the rice genome, insertions and eliminations of transposable elements have generated numerous transposon insertion polymorphisms (TIPs). Common wild rice (O. rufipogon Griff.), the ancestor of Asian cultivated rice (O. sativa L.), carries abundant genetic variations. To find subspecies-specific (SS) markers that can distinguish O. sativa ssp. indica and ssp. japonica, some long terminal repeat (LTR) sequences (sc1-14) of AA genome-specific RIRE retrotransposon were isolated from O. rufipogon genome. Sequences sc1 and sc12 were successfully utilized to develop the SS marker system based on retrotransposon inserted position polymorphisms. Twenty-two SS markers (ssi1-9, ssj1-13) were developed, where ssi1-9 are the indica-specific types, and ssj1-13 the japonica-specific types. The average accuracy of these markers in distinguishing the two subspecies is over 85%. SS marker ssj-10 can distinguish the two subspecies at 100% accuracy. Principal component analysis (PCA) showed that these markers could successfully distinguish indica from japonica varieties, regardless of their geographical origin.

B cell lymphoma (BCL) has a higher degree of malignancy and complicated pathogenic mechanism. Regulatory T cells (Treg cells) are known to exert certain immune suppression functions, in addition to immune mediating effects. Recent studies have revealed the role of Treg cells in pathogenesis and progression of multiple malignant tumors. This study therefore investigated the functional role and related mechanism of Treg cells in BCL. A cohort of thirty patients who were diagnosed with BCL in our hospital between January 2013 and December 2014. Another thirty healthy individuals were recruited. Peripheral blood mononuclear cells (PBMCs) were separated and analyzed for the ratio of CD4+/CD25+ Treg cells. The mRNA expression levels of Foxp3, transforming growth factor (TGF)-β1 and interleukin (IL)-10 genes were quantified by real-time PCR, while their serum levels were determined by enzyme-linked immunosorbent assay (ELISA). Meanwhile all laboratory indexes for patients were monitored during the complete remission (CR) stage. BCL patients significantly elevated ratio of CD4+/CD25+ Treg cells, which were decreased at CR stage. mRNA levels of Foxp3, TGF-β1 and IL-10, in addition to protein levels of TGF-β1 and IL-10 were potentiated in lymphoma patients but decreased in CR patients (P

To investigate the different outcomes by dexamethasone in adults immune thrombocytopenia purpura (ITP) with different types of platelet specific-autoantibodies.A total of 185 ITP were enrolled, 61 males and 124 females, with a median age of 42 (18-83) years, including 117 newly diagnosed, 35 persistent, and 33 chronic cases. All the patients received the dexamethasone at an initial dose of 40 mg per day for 4 days and a low dose of 5-10 mg for 3-4 weeks. The platelet specific-autoantibodies were identified by the modified monoclonal antibody-specific immobilization of platelet antigen (MAIPA) assay.Among the IgG positive patients, the response rates in anti-GPIIb/IIIa antibody, anti-GPIbα antibody, both antibody positive, and both antibody negative were 87.5%, 50.0%, 68.0%, and 72.3% (χ²=11.489, P0.05), respectively. Among the IgM positive patients, the response rates in the four groups were 82.1%, 71.4%, 61.9%, and 68.9% (χ²=2.719, P=0.437), respectively. Among the GPIbα antibody positive patients, the response rates in IgG alone, IgM alone, both positive, and both negative were 52.4%, 59.1%, 76.1%, and 77.9% (χ²=10.811, P0.05), respectively. Among the GPIIb/IIIa antibody positive patients, the response rates in the four groups were 73.3%, 71.0%, 78.6%, and 66.3% (χ²=1.374, P=0.719), respectively.ITP patients with GPIbα-IgG antibody have worse response to dexamethasone treatment.

This study aimed to explore the association between the percentage of reticulated platelets (RP%) and infection, and analyze the value of combined measurement of RP% with other inflammatory indicators in diagnosing infection. A total of 190 patients with signs and symptoms suspicious of infection were included in the infection group, and 70 healthy subjects with comparable percentages of gender and age were included in the control group. Peripheral white blood cell (WBC) count, percentage of neutrophils (N%), platelet count, C-reactive protein (CRP), procalcitonin (PCT), RP%, and axillary temperature were recorded. Dynamic changes in RP% with infection were measured to analyze the association between RP% and infection. The receiver operating characteristic curve was used to evaluate the value of each inflammatory indicator in diagnosing infection and analyze the diagnostic value of the combined adoption of multiple inflammatory indicators. RP% was significantly higher in the infection group than in the noninfection and control groups. The sensitivity and specificity for diagnosing infection were, respectively, 91.78% and 93.18% when RP% and CRP were used in combination, 90.41% and 90.90% when RP% and PCT were used in combination, and 100% and 100% when RP%, CRP, and PCT were used in combination. RP% changed dynamically with the progression of infection and recovered to lower than 5.5% at 2 to 7 days before the body temperature recovered to a normal level. The diagnostic value of RP% was the highest. A combined use with CRP/PCT could improve the sensitivity and specificity in the early diagnosis of infectious diseases.

Immune thrombocytopenia (ITP) is characterized by platelet clearance mediated primarily by autoantibodies against the platelet GPIIbIIIa and/or GPIbα. Steroid therapy is a first-line treatment for ITP. However, some patients are refractory to this therapy and currently no method can predict which patients will respond. To evaluate whether steroids are equally efficacious in treating patients with ITP caused by anti-GPIIbIIIa versus anti-GPIbα antibodies, we performed a retrospective study on 176 newly diagnosed patients with acute ITP who had severe bleeding symptoms and were admitted as resident patients to the hospital. The patients were treated first with intravenous administration of high-dose dexamethasone (DXM), followed by oral administration of prednisone. Response to therapy was observed in a majority of patients with antibodies specific for GPIIbIIIa (31/43) or without detectable antibodies against either GPIIbIIIa or GPIbα (36/45). In contrast, the steroid response was significantly lower in patients with anti-GPIbα antibodies (9/34) or with antibodies against both GPIbα and GPIIbIIIa (16/54). The preliminary findings of this study suggest that in future prospective clinical trials including corticosteroids, the anti-GPIbα, and -GPIIbIIIa status should be assessed in order to test its potential relevance in deciding future treatments.

Abstract 1323 Poster Board I-345 Background Idiopathic thrombocytopenic purpura (ITP) is a common autoimmune disease characterized by autoantibody-induced platelet destruction and consequent bleeding disorders. Despite considerable investigation, the pathogenesis of ITP remains incompletely understood, and we currently lack a consensus for therapy. The major targeted platelet autoantigens are located on two distinctive platelet receptors; the GPIIbIIIa and GPIb complexes. It has been reported that thrombocytopenia induced by anti-GPIba antibodies, which may differ from that induced by anti-GPIIbIIIa, can be mediated via an Fc-independent pathway. We further demonstrated in a murine model that anti-GPIba-mediated-ITP is less responsive to IVIG treatment (Blood. 2006; 108(3):943-6), which is consistent with a subsequent retrospective study in human ITP patients. Since IVIG is expensive and steroid therapy is the first line of treatment for most patients, particularly in developing countries, we tested whether gluococorticosteroid therapy has equal efficacy in ITP patients caused by these two different antibodies. Patients and Methods A total of 107 ITP patients (71 females and 36 males) were recruited for the present study. Patients were first treated with Dexamethasone (DXM, 20mg/day x 3-5 days), then changed to oral administration of Prednisone (1mg/kg/day). The dose of Prednisone was gradually decreased and maintained for = 30 days. The patients were considered as responders to the therapy if no obvious haemorrhage was detected and their platelet counts were raised to = 50 × 109/L or increased by = 30 × 109/L from their original platelet count before treatment. All patients' plasma samples were collected before therapy and specific autoantibodies against GPIIbIIIa and/or the GPIb complex were measured with a monoclonal antibody immobilization of platelet antigen assay (MAIPA). Results Among the 107 patients, 23% (25/107) had antibodies against GPIIbIIIa, 18% (19/107) had antibodies against the GPIb complex, 34% (36/107) had antibodies against both the GPIIbIIIa and GPIb complex, and 25% (27/107) had no detectable antibody to either of these two antigens. We found that a majority of the patients with antibodies against GPIIbIIIa (15/22) were sensitive to the steroid therapy, which is significantly different from those with antibodies against the GPIb complex (5/19) (X2 = 7.15, P 0.05), there is a tendency that patients with double positive antibodies were less responsive to steroid therapy therapy. The most sensitive patients for this therapy were those without detectable antibodies to either of these two autoantigens (21/27). Conclusions Our data suggest that anti-GPIb-mediated ITP may be less responsive to both IVIG and steroid therapies when compared to anti-GPIIbIIIa-mediated ITP. The pathogenesis and treatment of anti-GPIb-mediated ITP merits further investigation. Disclosures No relevant conflicts of interest to declare.