Human platelet antigen 1-6, 9 and 15 in the Iranian population: An anthropological genetic analysis

The Impact of Human Platelet Antigen Allele on Antiplatelet Antibodies and Cryoglobulins in Patients with Primary Immune Thrombocytopenia and Hepatitis C Virus-Associated Immune Thrombocytopenia

Background And Objectives

Human platelet antigens (HPAs) are alloantigens associated with antiplatelet alloantibodies and the risk of immune thrombocytopenia (ITP). However, few studies have investigated associations among HPAs, antiplatelet autoantibodies, and cryoglobulins.

Methods

We enrolled 43 patients with primary ITP, 47 with hepatitis C virus-associated ITP (HCV-ITP), 21 with hepatitis B virus-associated ITP (HBV-ITP), 25 controls with HCV, and 1013 normal controls. We analyzed HPA allele frequencies, including HPA1-6 and 15, antiplatelet antibodies binding to platelet glycoprotein (GP) IIb/IIIa, Ia/IIa, Ib/IX, IV, human leukocyte antigen class I, cryoglobulin IgG/A/M, and their associations with thrombocytopenia.

Results

In the ITP cohort, HPA2ab, rather than HPA2aa, predicted a low platelet count. HPA2b was associated with the risk of developing ITP. HPA15b was correlated with multiple antiplatelet antibodies. In HCV-ITP patients, HPA3b was correlated with anti-GPIIb/IIIa antibodies. HCV-ITP patients with anti-GPIIb/IIIa antibodies had a higher positive rate of cryoglobulin IgG and IgA compared with those without anti-GPIIb/IIIa antibodies. Overlapping detection was also found among other antiplatelet antibodies and cryoglobulins. Like the antiplatelet antibodies, cryoglobulins were associated with clinical thrombocytopenia, implying their close relationship. Finally, we extracted cryoglobulins to confirm the exhibition of cryoglobulin-like antiplatelet antibodies. In contrast, in primary ITP patients, HPA3b was correlated with cryoglobulin IgG/A/M rather than anti-GPIIb/IIIa antibodies.

Conclusion

HPA alleles were associated with antiplatelet autoantibodies and had different impacts in primary ITP and HCV-ITP patients. HCV-ITP was considered to be a symptom of mixed cryoglobulinemia in HCV patients. The pathophysiology may differ between these two groups.

Oncolytic Virotherapy in Solid Tumors: The Challenges and Achievements

Oncolytic virotherapy (OVT) is a promising approach in cancer immunotherapy. Oncolytic viruses (OVs) could be applied in cancer immunotherapy without in-depth knowledge of tumor antigens. The capability of genetic modification makes OVs exciting therapeutic tools with a high potential for manipulation. Improving efficacy, employing immunostimulatory elements, changing the immunosuppressive tumor microenvironment (TME) to inflammatory TME, optimizing their delivery system, and increasing the safety are the main areas of OVs manipulations. Recently, the reciprocal interaction of OVs and TME has become a hot topic for investigators to enhance the efficacy of OVT with less off-target adverse events. Current investigations suggest that the main application of OVT is to provoke the antitumor immune response in the TME, which synergize the effects of other immunotherapies such as immune-checkpoint blockers and adoptive cell therapy. In this review, we focused on the effects of OVs on the TME and antitumor immune responses. Furthermore, OVT challenges, including its moderate efficiency, safety concerns, and delivery strategies, along with recent achievements to overcome challenges, are thoroughly discussed.

The association of disease type, pre-transplant hemoglobin level and platelet count with transfusion requirement after autologous hematopoietic stem cell transplantation

BACKGROUND

Autologous hematopoietic stem cell transplantation (auto-HSCT) has become an effective treatment for a wide range of hematologic and non-hematologic diseases. Patients undergoing HSCT might require multiple platelets and red blood cell (RBC) transfusions during aplasia phase until engraftment, which could profoundly affect patients' conditions. Identification of risk factors associated with blood product requirements could help in decreasing transfusion-related complications. We evaluated the association of disease type, pre-transplant hemoglobin level, and pre-transplant platelet count with RBC/platelet transfusion requirement after auto-HSCT.

METHODS

In this retrospective study, 324 patients diagnosed with multiple myeloma (MM), Hodgkin disease (HD), and non-Hodgkin lymphoma (NHL) and underwent auto-HSCT were included. The associations of disease type, pre-transplant hemoglobin level, and platelet count with post-transplant packed cell and single-/random-donor platelet transfusions were evaluated.

RESULTS

Our study results illustrated that the higher pre-transplant hemoglobin level significantly decreased the post-HSCT requirement for packed cell (IRR=0.81, [CI: 9.73-0.90], P=0.0001), while the pre-transplant platelet showed no significant relationship with platelet requirement after HSCT. HD was associated with increment in packed cell (IRR=2.04, [CI: 1.35-3.08], P=0.001) and single donor platelet (IRR=1.39, [CI: 1.09-1.78], P=0.008) requirement after transplant. The trends showed that a higher platelet level led to a lower need for platelet transfusion.

CONCLUSION

Pre-transplant hemoglobin level could be valuable markers for predicting post-HSCT RBC requirements and might be beneficial for better management of transfusion requirements to minimize the transfusion-related complications. Patients with HD seem to be more prone to blood product requirements post-transplant.