Naïve CD4+ T Cell Lymphopenia and Apoptosis in Chronic Hepatitis C Virus Infection Is Driven by the CD31+ Subset and Is Partially Normalized in Direct-Acting Antiviral Treated Persons

Lymphocytes in Patients with Chronic Active Epstein-Barr Virus Disease Exhibited Elevated PD-1/PD-L1 Expression and a Prevailing Th2 Immune Response

Background And Objectives

Chronic active Epstein-Barr virus disease (CAEBV) is a proliferative disease of EBV+ T or natural killer (NK) cells with an unclear pathogenesis. This study aimed to examine the frequency and exhaustion levels of lymphocyte subsets in patients with CAEBV to further investigate the pathogenesis.

Methods

Using flow cytometry, we detected the frequency, expression levels of programmed cell death 1 (PD-1) and programmed death ligand 1 (PD-L1), and EBV infection status of peripheral T subsets and NK cells in patients with CAEBV and healthy individuals.

Results

24 patients and 15 healthy individuals were enrolled in this study. Patients showed notably higher expression levels of PD-1 and PD-L1 in peripheral T subsets and NK cells compared to healthy individuals (P < 0.05). EBV+ lymphocytes exhibited significantly higher PD-L1 expression levels than EBV- lymphocytes. Additionally, the frequency of effector memory T (Tem) cells was significantly increased in patients, and the PD-L1 expression level was positively correlated with the EBV load. Besides, helper T cell 2 (Th2) immune bias, also favoring EBV amplification, was found in patients, including increased Th2 cell frequency, enhanced response capacity, and elevated serum levels of associated cytokines. The distribution and PD-1 expression levels of peripheral T subsets returned to normal in patients who responded to PD-1 blockade therapy.

Conclusions

The up-regulation of the PD-1/PD-L1 pathway of peripheral T and NK cells and Th2 immune predominance jointly promoted EBV replication and the development of CAEBV. PD-1 blockade therapy reduced the PD-1 expression level of lymphocytes and helped normalize the distribution of the T subsets.

Aleukemic Acute Promyelocytic Leukemia: How Concomitant HIV, Hepatitis C, and Chronic Alcohol Use Disorder May Have Hidden an Underlying Malignancy

BACKGROUND Acute promyelocytic leukemia (APL) is a rare subtype of acute myeloid leukemia (AML) and is characterized by a genetic translocation affecting the retinoic acid receptor-alpha gene, leading to blockage in the differentiation of granulocytic cells. The accumulation of promyelocytes in bone marrow leads to cytopenias and life-threatening coagulopathies. Definitive diagnosis is made with bone marrow biopsy. Differentiation of APL from other leukemias is important to appropriately treat with all-trans retinoic acid (ATRA) and arsenic trioxide. Patients with HIV are at a higher risk to develop AML. This article identifies how multiple comorbidities and social factors can contribute to difficulties in diagnosing AML. CASE REPORT We present a 67-year-old man with a past medical history of hypertension and substance use disorder who presented with progressive exertional dyspnea and was found to have HIV, chronic hepatitis C, and APL with pancytopenia. His bone marrow biopsy confirmed AML. This was a case of co-existing HIV and aleukemic leukemia. CONCLUSIONS APL can present with pancytopenia, weakness, failure to thrive, or bleeding complications, which can be similar to presentations of those diagnosed with HIV. Diagnosis of APL can be differentiated between hypergranular and hypogranular; our patient demonstrated APL with only 52% blasts, which can make for a challenging diagnosis. Given increased mortality of APL, immediate ATRA therapy is warranted. Aleukemic leukemia is a rare presentation typically accompanied by skin manifestations. Our case highlights the importance of having high clinical suspicion for malignancy in patients with comorbidities that can interfere with the classic presentation of leukemia.

Variable Normalization of Naïve CD4+ Lymphopenia and Markers of Monocyte and T Cell Activation over the Course of Direct-Acting Anti-Viral Treatment of Chronic Hepatitis C Virus Infection

Chronic hepatitis C virus (HCV) infection is associated with naïve CD4+ T cell lymphopenia and long-standing/persistent elevation of cellular and soluble immune activation parameters, the latter heightened in the setting of HIV co-infection. The underlying mechanisms are not completely understood. However, we recently reported that accelerated peripheral cell death may contribute to naïve CD4+ T cell loss and that mechanistic relationships between monocyte activation, T cell activation, and soluble inflammatory mediators may also contribute. Chronic HCV infection can be cured by direct-acting anti-viral (DAA) therapy, and success is defined as sustained virological response (SVR, undetectable HCV RNA (ribonucleic acid) at 12 weeks after DAA treatment completion). However, there is no general consensus on the short-term and long-term immunological outcomes of DAA therapy. Here, we consolidate previous reports on the partial normalization of naïve CD4+ lymphopenia and T cell immune activation and the apparent irreversibility of monocyte activation following DAA therapy in HCV infected and HCV/HIV co-infected individuals. Further, advanced age and cirrhosis are associated with delayed or abrogation of immune reconstitution after DAA therapy, an indication that non-viral factors also likely contribute to host immune dysregulation in HCV infection.