Restoration of HBV-specific CD8+ T-cell responses by sequential low-dose IL-2 treatment in non-responder patients after IFN-α therapy

Safety and efficacy of 48-week pegylated interferon-α-2b therapy in patients with hepatitis B virus-related compensated liver cirrhosis: a pilot observational study

Background

Pegylated interferon-α (PEG-IFN-α) therapy could decrease hepatitis B surface antigen (HBsAg) and improve long-term prognosis of hepatitis B virus (HBV) infection. However, studies on safety and efficacy of PEG-IFN-α for patients with HBV-related cirrhosis are limited.

Methods

This was a single-center study. Fifty-four patients with HBV-related compensated cirrhosis were enrolled. All patients received subcutaneous injection of PEG-IFN-α-2b 180 μg per week for 48 weeks. The monotherapy of PEG-IFN-α-2b was used for treatment-naïve patients, while addition of PEG-IFN-α-2b to on-going nucleos(t)ide analogs (NAs) was used for NAs-experienced patients. Clinical symptoms, laboratory tests, examination indicators, and adverse events were collected at each observational time point.

Results

Forty-two patients achieved undetectable serum HBV DNA at 48 weeks post-therapy. HBsAg level was significantly reduced at 48 weeks post-therapy (227.2 IU/mL vs. 1,668 IU/mL; p < 0.001), especially in NAs-experienced patients (161.0 IU/mL vs. 1,207 IU/mL; p = 0.005). Three patients achieved HBsAg loss, and two of them obtained HBsAg seroconversion. There were no significant differences in liver stiffness measurement, thickness and length of spleen, or diameter of portal vein between baseline and 48 weeks post-therapy (p > 0.05). The aminotransferase levels were increased, while white blood cells, neutrophils, and platelets counts were decreased during PEG-IFN-α-2b therapy (p < 0.05), especially in treatment-naïve patients. Three patients discontinued PEG-IFN-α-2b therapy due to severe adverse events. No patients suffered with virological breakthrough or progressed to end-stage liver diseases during observational period.

Conclusion

A finite course of PEG-IFN-α-2b therapy was well-tolerated, and reduced HBsAg level without accelerating disease progression in patients with HBV-related compensated cirrhosis.

Clinical trial registration

This trial is a part of ZhuFeng Project (ClinicalTrials.gov, identifier NCT04035837).

Efficacy of short-term Peg-IFN α-2b treatment in chronic hepatitis B patients with ultra-low HBsAg levels: a retrospective cohort study

PURPOSE

Peginterferon alfa-2b (Peg-IFN α-2b) has demonstrated superior efficacy over nucleos(t)ide analogs (NAs) in the treatment of chronic hepatitis B (CHB), particularly among patients with low levels of hepatitis B surface antigen (HBsAg). This study aims to determine whether patients with ultra-low HBsAg levels (< 200 IU/mL) can achieve significantly higher clinical cure rates with abbreviated courses of Peg-IFN α-2b therapy.

METHODS

In this retrospective analysis, CHB patients with HBsAg levels below 200 IU/mL were categorized into a Peg-IFN α-2b group and a control group. The Peg-IFN α-2b group received Peg-IFN α-2b for a minimum of 24 weeks, with the possibility of early discontinuation upon achieving HBsAg clearance, and were followed through week 48. The control group remained untreated for hepatitis B virus (HBV), and was observed for 24 weeks. HBsAg clearance rates were compared between groups. Univariate and multivariate logistic regression analyses were employed to identify factors associated with HBsAg clearance .

RESULTS

By week 24, the HBsAg clearance rate in the Peg-IFN α-2b group was notably 52.1% (38/73), contrasting sharply with the mere 1.3% (1/77) observed in the control group. Within the Peg-IFN α-2b group, a substantial 97.3% (71/73) of patients noted a reduction in HBsAg levels. Besides, the decision to continue or discontinue treatment after the 24-week mark had no significant impact on the HBsAg clearance rate at week 48. Multivariable analysis pinpointed baseline HBsAg levels (OR = 0.984, p = 0.001) and the presence of fatty liver (OR = 5.960, p = 0.033) as independent predictors of HBsAg clearance.

CONCLUSION

Our findings confirm that a 24-week course of Peg-IFN α-2b yields robust efficacy in CHB patients with ultra-low HBsAg levels. Prolonging treatment beyond the 24-week threshold is deemed unnecessary. Both baseline HBsAg level and the presence of fatty liver emerged as significant predictors for HBsAg clearance.

Optimized RNA interference therapeutics combined with interleukin-2 mRNA for treating hepatitis B virus infection

This study aimed to develop a pan-genotypic and multifunctional small interfering RNA (siRNA) against hepatitis B virus (HBV) with an efficient delivery system for treating chronic hepatitis B (CHB), and explore combined RNA interference (RNAi) and immune modulatory modalities for better viral control. Twenty synthetic siRNAs targeting consensus motifs distributed across the whole HBV genome were designed and evaluated. The lipid nanoparticle (LNP) formulation was optimized by adopting HO-PEG2000-DMG lipid and modifying the molar ratio of traditional polyethylene glycol (PEG) lipid in LNP prescriptions. The efficacy and safety of this formulation in delivering siHBV (tLNP/siHBV) along with the mouse IL-2 (mIL-2) mRNA (tLNP/siHBVIL2) were evaluated in the rAAV-HBV1.3 mouse model. A siRNA combination (terms "siHBV") with a genotypic coverage of 98.55% was selected, chemically modified, and encapsulated within an optimized LNP (tLNP) of high efficacy and security to fabricate a therapeutic formulation for CHB. The results revealed that tLNP/siHBV significantly reduced the expression of viral antigens and DNA (up to 3log10 reduction; vs PBS) in dose- and time-dependent manners at single-dose or multi-dose frequencies, with satisfactory safety profiles. Further studies showed that tLNP/siHBVIL2 enables additive antigenic and immune control of the virus, via introducing potent HBsAg clearance through RNAi and triggering strong HBV-specific CD4+ and CD8+ T cell responses by expressed mIL-2 protein. By adopting tLNP as nucleic acid nanocarriers, the co-delivery of siHBV and mIL-2 mRNA enables synergistic antigenic and immune control of HBV, thus offering a promising translational therapeutic strategy for treating CHB.

Reconstitution of double-negative T cells after cord blood transplantation and its predictive value for acute graft-versus-host disease

BACKGROUND

With an increasing number of patients with hematological malignancies being treated with umbilical cord blood transplantation (UCBT), the correlation between immune reconstitution (IR) after UCBT and graft-versus-host disease (GVHD) has been reported successively, but reports on double-negative T (DNT) cell reconstitution and its association with acute GVHD (aGVHD) after UCBT are lacking.

METHODS

A population-based observational study was conducted among 131 patients with hematological malignancies who underwent single-unit UCBT as their first transplant at the Department of Hematology, the First Affiliated Hospital of USTC, between August 2018 and June 2021. IR differences were compared between the patients with and without aGVHD.

RESULTS

The absolute number of DNT cells in the healthy Chinese population was 109 (70-157)/μL, accounting for 5.82 (3.98-8.19)% of lymphocytes. DNT cells showed delayed recovery and could not reach their normal levels even one year after transplantation. Importantly, the absolute number and percentage of DNT cells were significantly higher in UCBT patients without aGVHD than in those with aGVHD within one year ( F = 4.684, P = 0.039 and F = 5.583, P = 0.026, respectively). In addition, the number of DNT cells in the first month after transplantation decreased significantly with the degree of aGVHD increased, and faster DNT cell reconstitution in the first month after UCBT was an independent protective factor for aGVHD (HR = 0.46, 95% confidence interval [CI]: 0.23-0.93; P = 0.031).

CONCLUSIONS

Compared to the number of DNT cells in Chinese healthy people, the reconstitution of DNT cells in adults with hematological malignancies after UCBT was slow. In addition, the faster reconstitution of DNT cells in the early stage after transplantation was associated with a lower incidence of aGVHD.

Hepatitis B: Model Systems and Therapeutic Approaches

Hepatitis B virus (HBV) infection is a major global health issue and ranks among the top causes of liver cirrhosis and hepatocellular carcinoma. Although current antiviral medications, including nucleot(s)ide analogs and interferons, could inhibit the replication of HBV and alleviate the disease, HBV cannot be fully eradicated. The development of cellular and animal models for HBV infection plays an important role in exploring effective anti-HBV medicine. During the past decades, advancements in several cell culture systems, such as HepG2.2.15, HepAD38, HepaRG, hepatocyte-like cells, and primary human hepatocytes, have propelled the research in inhibiting HBV replication and expression and thus enriched our comprehension of the viral life cycle and enhancing antiviral drug evaluation efficacy. Mouse models, in particular, have emerged as the most extensively studied HBV animal models. Additionally, the present landscape of HBV therapeutics research now encompasses a comprehensive assessment of the virus's life cycle, targeting numerous facets and employing a variety of immunomodulatory approaches, including entry inhibitors, strategies aimed at cccDNA, RNA interference technologies, toll-like receptor agonists, and, notably, traditional Chinese medicine (TCM). This review describes the attributes and limitations of existing HBV model systems and surveys novel advancements in HBV treatment modalities, which will offer deeper insights toward discovering potentially efficacious pharmaceutical interventions.

New sights of low dose IL-2: Restoration of immune homeostasis for viral infection

Viral infection poses a significant threat to human health. In addition to the damage caused by viral replication, the immune response it triggers often leads to more serious adverse consequences. After the occurrence of viral infection, in addition to the adverse consequences of infection, chronic infections can also lead to virus-related autoimmune diseases and tumours. At the same time, the immune response triggered by viral infection is complex, and dysregulated immune response may lead to the occurrence of immune pathology and macrophage activation syndrome. In addition, it may cause secondary immune suppression, especially in patients with compromised immune system, which could lead to the occurrence of secondary infections by other pathogens. This can often result in more severe clinical outcomes. Therefore, regarding the treatment of viral infections, restoring the balance of the immune system is crucial in addition to specific antiviral medications. In recent years, scientists have made an interesting finding that low dose IL-2 (ld-IL-2) could potentially have a crucial function in regulating the immune system and reducing the chances of infection, especially viral infection. Ld-IL-2 exerts immune regulatory effects in different types of viral infections by modulating CD4+ T subsets, CD8+ T cells, natural killer cells, and so on. Our review summarised the role of IL-2 or IL-2 complexes in viral infections. Ld-IL-2 may be an effective strategy for enhancing host antiviral immunity and preventing infection from becoming chronic; additionally, the appropriate use of it can help prevent excessive inflammatory response after infection. In the long term, it may reduce the occurrence of infection-related autoimmune diseases and tumours by promoting the restoration of early immune homeostasis. Furthermore, we have also summarised the application of ld-IL-2 in the context of autoimmune diseases combined with viral infections; it may be a safe and effective strategy for restoring immune homeostasis without compromising the antiviral immune response. In conclusion, focusing on the role of ld-IL-2 in viral infections may provide a new perspective for regulating immune responses following viral infections and improving prognosis.

The novel mechanism facilitating chronic hepatitis B infection: immunometabolism and epigenetic modification reprogramming

Hepatitis B Virus (HBV) infections pose a global public health challenge. Despite extensive research on this disease, the intricate mechanisms underlying persistent HBV infection require further in-depth elucidation. Recent studies have revealed the pivotal roles of immunometabolism and epigenetic reprogramming in chronic HBV infection. Immunometabolism have identified as the process, which link cell metabolic status with innate immunity functions in response to HBV infection, ultimately contributing to the immune system's inability to resolve Chronic Hepatitis B (CHB). Within hepatocytes, HBV replication leads to a stable viral covalently closed circular DNA (cccDNA) minichromosome located in the nucleus, and epigenetic modifications in cccDNA enable persistence of infection. Additionally, the accumulation or depletion of metabolites not only directly affects the function and homeostasis of immune cells but also serves as a substrate for regulating epigenetic modifications, subsequently influencing the expression of antiviral immune genes and facilitating the occurrence of sustained HBV infection. The interaction between immunometabolism and epigenetic modifications has led to a new research field, known as metabolic epigenomics, which may form a mutually reinforcing relationship with CHB. Herein, we review the recent studies on immunometabolism and epigenetic reprogramming in CHB infection and discuss the potential mechanisms of persistent HBV infection. A deeper understanding of these mechanisms will offer novel insights and targets for intervention strategies against chronic HBV infection, thereby providing new hope for the treatment of related diseases.

CD8 cis-targeted IL-2 drives potent antiviral activity against hepatitis B virus

CD8+ T cells are key antiviral effectors against hepatitis B virus (HBV), yet their number and function can be compromised in chronic infections. Preclinical HBV models displaying CD8+ T cell dysfunction showed that interleukin-2 (IL-2)-based treatment, unlike programmed cell death ligand 1 (PD-L1) checkpoint blockade, could reverse this defect, suggesting its therapeutic potential against HBV. However, IL-2's effectiveness is hindered by its pleiotropic nature, because its receptor is found on various immune cells, including regulatory T (Treg) cells and natural killer (NK) cells, which can counteract antiviral responses or contribute to toxicity, respectively. To address this, we developed a cis-targeted CD8-IL2 fusion protein, aiming to selectively stimulate dysfunctional CD8+ T cells in chronic HBV. In a mouse model, CD8-IL2 boosted the number of HBV-reactive CD8+ T cells in the liver without substantially altering Treg or NK cell counts. These expanded CD8+ T cells exhibited increased interferon-γ and granzyme B production, demonstrating enhanced functionality. CD8-IL2 treatment resulted in substantial antiviral effects, evidenced by marked reductions in viremia and antigenemia and HBV core antigen-positive hepatocytes. In contrast, an untargeted CTRL-IL2 led to predominant NK cell expansion, minimal CD8+ T cell expansion, negligible changes in effector molecules, and minimal antiviral activity. Human CD8-IL2 trials in cynomolgus monkeys mirrored these results, achieving a roughly 20-fold increase in peripheral blood CD8+ T cells without affecting NK or Treg cell numbers. These data support the development of CD8-IL2 as a therapy for chronic HBV infection.

A novel TRIM22 gene polymorphism promotes the response to PegIFNα therapy through cytokine-cytokine receptor interaction signaling pathway in chronic hepatitis B

IMPORTANCE

Pegylated interferon alfa (PegIFNα) has limited efficacy in the treatment of chronic hepatitis B (CHB). Although many biomarkers related to hepatitis B virus (HBV) have been proposed to stratify patients, the response rate to PegIFNα is still unsatisfactory. Herein, our data suggest that the single-nucleotide polymorphism (SNP) rs10838543 in TRIM22 potentiates a positive clinical response to PegIFNα treatment in patients with hepatitis B e antigen-positive CHB by increasing the levels of IFNL1, CCL3, and CCL5. These observations can help guide treatment decisions for patients with CHB to improve the response rate to PegIFNα.

Recent advances in understanding T cell activation and exhaustion during HBV infection

Chronic hepatitis B virus (HBV) infection remains a major public health concern globally, and T cell responses are widely believed to play a pivotal role in mediating HBV clearance. Accordingly, research on the characteristics of HBV-specific T cell responses, from activation to exhaustion, has advanced rapidly. Here, we summarize recent developments in characterizing T cell immunity in HBV infection by reviewing basic and clinical research published in the last five years. We provide a comprehensive summary of the mechanisms that induce effective anti-HBV T cell immunity, as well as the latest developments in understanding T cell dysfunction in chronic HBV infection. Furthermore, we briefly discuss current novel treatment strategies aimed at restoring anti-HBV T cell responses.

Oncostatin M Induces IFITM1 Expression to Inhibit Hepatitis B Virus Replication Via JAK-STAT Signaling

BACKGROUND & AIMS

Functional cure is achieved by a limited number of patients with chronic hepatitis B (CHB) after nucleotide analogue(s) and interferon treatment. It is urgent to develop therapies that can help a larger proportion of patients achieve functional cure. The present study was designed to explore the anti-hepatitis B virus (HBV) potency of interleukin-6 family cytokines and to characterize the underlying mechanisms of the cytokine displaying the highest anti-HBV potency.

METHODS

HBV-infected cells were used to screened the anti-HBV potency of interleukin-6 family cytokines. The concentration of oncostatin M (OSM) in patients with chronic HBV infection was examined by enzyme-linked immunosorbent assay. The underlying mechanism of OSM anti-HBV was explored through RNA-seq. C57BL/6 mice injected with rAAV8-1.3HBV were used to explore the suppression effect of OSM on HBV in vivo.

RESULTS

OSM is the most effective of the interleukin-6 family cytokines for suppression of HBV replication (percentage of average inhibition: hepatitis B surface antigen, 34.44%; hepatitis B e antigen, 32.52%; HBV DNA, 61.57%). Hepatitis B e antigen-positive CHB patients with high OSM levels had lower hepatitis B surface antigen and hepatitis B e antigen than those with low levels. OSM activated JAK-STAT signaling pathway promoting the formation of STAT1-IRF9 transcription factor complex. Following this, OSM increased the expression of various genes with known functions in innate and adaptive immunity, which was higher expression in patients with CHB in immune clearance phase than in immune tolerance phase (data from GEO: GSE65359). Interferon-induced transmembrane protein 1, one of the most differentially expressed genes, was identified as an HBV restriction factor involved in OSM-mediated anti-HBV effect. In vivo, we also found OSM significantly inhibited HBV replication and induced expression of antiviral effector interferon-induced transmembrane protein 1.

CONCLUSIONS

Our study shows that OSM remodels the immune response against HBV and exerts potent anti-HBV activity, supporting its further development as a potential therapy for treating CHB.

Establishment and validation of a novel risk model based on CD8T cell marker genes to predict prognosis in thyroid cancer by integrated analysis of single-cell and bulk RNA-sequencing

Papillary thyroid cancer (PTC) is a histological type of thyroid cancer, and CD8T is important for the immune response. The single-cell RNA data were acquired from Gene Expression Omnibus. SingleR package was used for cluster identification, and CellChat was exploited to evaluate the interaction among several cell types. Bulk RNA data obtained from the cancer genome atlas were used for determination of prognosis using Kaplan-Meier and Receiver Operating Characteristic curve. The Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analysis were applied for assessment of function enrichment. The drug sensitivity was calculated in Gene Set Cancer Analysis. The regulatory network was constructed by STRING and Cytoscape. We identified 23 cell clusters and 10 cell types. Cell communication results showed CD8T cell was vital among all immune cell types. Enrichment analysis found the marker genes of CD8T cell was enriched in some signal pathways related to tumor development. Overall, FAM107B and TUBA4A were considered as hub genes and used to construct a risk model. Most immune checkpoint expressions were upregulated in tumor group. Tumor mutation burden results indicated that prognosis of PTC was not related to the mutation of hub genes. Drug sensitivity analysis showed some drugs could be effectively used for the treatment of PTC, and regulatory network identified some targets for the immunotherapy. A 2-gene model of PTC was developed based on the single-cell RNA and bulk RNA data. Besides, we found CD8T was essential for the immune response in PTC.

RNA binding protein TIAR modulates HBV replication by tipping the balance of pgRNA translation

The pregenomic RNA (pgRNA) of hepatitis B virus (HBV) serves not only as a bicistronic message RNA to translate core protein (Cp) and DNA polymerase (Pol), but also as the template for reverse transcriptional replication of viral DNA upon packaging into nucleocapsid. Although it is well known that pgRNA translates much more Cp than Pol, the molecular mechanism underlying the regulation of Cp and Pol translation efficiency from pgRNA remains elusive. In this study, we systematically profiled HBV nucleocapsid- and pgRNA-associated cellular proteins by proteomic analysis and identified TIA-1-related protein (TIAR) as a novel cellular protein that binds pgRNA and promotes HBV DNA replication. Interestingly, loss- and gain-of-function genetic analyses showed that manipulation of TIAR expression did not alter the levels of HBV transcripts nor the secretion of HBsAg and HBeAg in human hepatoma cells supporting HBV replication. However, Ribo-seq and PRM-based mass spectrometry analyses demonstrated that TIAR increased the translation of Pol but decreased the translation of Cp from pgRNA. RNA immunoprecipitation (RIP) and pulldown assays further revealed that TIAR directly binds pgRNA at the 5' stem-loop (ε). Moreover, HBV replication or Cp expression induced the increased expression and redistribution of TIAR from the nucleus to the cytoplasm of hepatocytes. Our results thus imply that TIAR is a novel cellular factor that regulates HBV replication by binding to the 5' ε structure of pgRNA to tip the balance of Cp and Pol translation. Through induction of TIAR translocation from the nucleus to the cytoplasm, Cp indirectly regulates the Pol translation and balances Cp and Pol expression levels in infected hepatocytes to ensure efficient viral replication.

Role of CXCR5+ CD8+ T cells in human hepatitis B virus infection

The replication of HBV in hepatocytes can be effectively inhibited by lifelong antiviral therapy. Because of the long-term presence of HBV reservoirs, the virus rebound frequently occurs once the treatment is stopped, which poses a considerable obstacle to the complete removal of the virus. In terms of gene composition, regulation of B cell action and function, CXCR5+ CD8+ T cells are similar to CXCR5+ CD4+ T follicular helper cells, while these cells are characterized by elevated programmed cell death 1 and cytotoxic-related proteins. CXCR5+ CD8+ T cells are strongly associated with progression in inflammatory and autoimmune diseases. In addition, CXCR5 expression on the surface of CD8+ T cells is mostly an indicator of memory stem cell-like failure in progenitor cells in cancer that are more responsive to immune checkpoint blocking therapy. Furthermore, the phenomena have also been demonstrated in some viral infections, highlighting the duality of the cellular immune response of CXCR5+ CD8+ T cells. This mini-review will focus on the function of CXCR5+ CD8+ T cells in HBV infection and discuss the function of these CD8+ T cells and the potential of associated co-stimulators or cytokines in HBV therapeutic strategies.

Expanded clinical-grade NK cells exhibit stronger effects than primary NK cells against HCMV infection

Cytomegalovirus (CMV) reactivation remains a common complication and leads to high mortality in patients who undergo allogeneic hematopoietic stem cell transplantation (allo-HSCT). Early natural killer (NK) cell reconstitution may protect against the development of human CMV (HCMV) infection post-HSCT. Our previous data showed that ex vivo mbIL21/4-1BBL-expanded NK cells exhibited high cytotoxicity against leukemia cells. Nevertheless, whether expanded NK cells have stronger anti-HCMV function is unknown. Herein, we compared the anti-HCMV functions of ex vivo expanded NK cells and primary NK cells. Expanded NK cells showed higher expression of activating receptors, chemokine receptors and adhesion molecules; stronger cytotoxicity against HCMV-infected fibroblasts; and better inhibition of HCMV propagation in vitro than primary NK cells. In HCMV-infected humanized mice, expanded NK cell infusion resulted in higher NK cell persistence and more effective tissue HCMV elimination than primary NK cell infusion. A clinical cohort of 20 post-HSCT patients who underwent adoptive NK cell infusion had a significantly lower cumulative incidence of HCMV infection (HR = 0.54, 95% CI = 0.32-0.93, p = 0.042) and refractory HCMV infection (HR = 0.34, 95% CI = 0.18-0.65, p = 0.009) than controls and better NK cell reconstitution on day 30 post NK cell infusion. In conclusion, expanded NK cells exhibit stronger effects than primary NK cells against HCMV infection both in vivo and in vitro.

Bispecific antibody targeting TGF-β and PD-L1 for synergistic cancer immunotherapy

The PD-1/PD-L1 signaling pathway plays a crucial role in cancer immune evasion, and the use of anti-PD-1/PD-L1 antibodies represents a significant milestone in cancer immunotherapy. However, the low response rate observed in unselected patients and the development of therapeutic resistance remain major obstacles to their clinical application. Accumulating studies showed that overexpressed TGF-β is another immunosuppressive factor apart from traditional immune checkpoints. Actually, the effects of PD-1 and TGF-β pathways are independent and interactive, which work together contributing to the immune evasion of cancer cell. It has been verified that blocking TGF-β and PD-L1 simultaneously could enhance the efficacy of PD-L1 monoclonal antibody and overcome its treatment resistance. Based on the bispecific antibody or fusion protein technology, multiple bispecific and bifunctional antibodies have been developed. In the preclinical and clinical studies, these updated antibodies exhibited potent anti-tumor activity, superior to anti-PD-1/PD-L1 monotherapies. In the review, we summarized the advances of bispecific antibodies targeting TGF-β and PD-L1 in cancer immunotherapy. We believe these next-generation immune checkpoint inhibitors would substantially alter the cancer treatment paradigm, especially in anti-PD-1/PD-L1-resistant patients.

A role for immune modulation in achieving functional cure for chronic hepatitis B among current changes in the landscape of new treatments

INTRODUCTION

Chronic hepatitis B (CHB) is rarely cured using available treatments. Barriers to cure are: 1) persistence of reservoirs of hepatitis B virus (HBV) replication and antigen production (HBV DNA); 2) high burden of viral antigens that promote T cell exhaustion with T cell dysfunction; 3) CHB-induced impairment of immune responses.

AREAS COVERED

We discuss options for new therapies that could address one or more of the barriers to functional cure, with particular emphasis on the potential role of immunotherapy.

EXPERT OPINION/COMMENTARY

Ideally, a sterilizing cure for CHB would translate into finite therapies that result in loss of HBV surface antigen and eradication of HBV DNA. Restoration of a functional adaptive immune response, a key facet of successful CHB treatment, remains elusive. Numerous strategies targeting the high viral DNA and antigen burden and aiming to restore the host immune responses will enter clinical development in coming years. Most patients are likely to require combinations of several drugs, personalized according to virologic and disease characteristics, patient preference, accessibility, and affordability. The management of CHB is a global health priority. Expedited drug development requires collaborations between regulatory agencies, scientists, clinicians, and within the industry to facilitate testing of the best drug combinations.

Current and novel modalities for management of chronic hepatitis B infection

Over 296 million people are estimated to have chronic hepatitis B viral infection (CHB), and it poses unique challenges for elimination. CHB is the result of hepatitis B virus (HBV)-specific immune tolerance and the presence of covalently closed circular DNA as mini chromosome inside the nucleus and the integrated HBV. Serum hepatitis B core-related antigen is the best surrogate marker for intrahepatic covalently closed circular DNA. Functional HBV "cure" is the durable loss of hepatitis B surface antigen (HBsAg), with or without HBsAg seroconversion and undetectable serum HBV DNA after completing a course of treatment. The currently approved therapies are nucleos(t)ide analogues, interferon-alpha, and pegylated-interferon. With these therapies, functional cure can be achieved in < 10% of CHB patients. Any variation to HBV or the host immune system that disrupts the interaction between them can lead to reactivation of HBV. Novel therapies may allow efficient control of CHB. They include direct acting antivirals and immunomodulators. Reduction of the viral antigen load is a crucial factor for success of immune-based therapies. Immunomodulatory therapy may lead to modulation of the host immune system. It may enhance/restore innate immunity against HBV (as toll-like-receptors and cytosolic retinoic acid inducible gene I agonist). Others may induce adaptive immunity as checkpoint inhibitors, therapeutic HBV vaccines including protein (HBsAg/preS and hepatitis B core antigen), monoclonal or bispecific antibodies and genetically engineered T cells to generate chimeric antigen receptor-T or T-cell receptor-T cells and HBV-specific T cells to restore T cell function to efficiently clear HBV. Combined therapy may successfully overcome immune tolerance and lead to HBV control and cure. Immunotherapeutic approaches carry the risk of overshooting immune responses causing uncontrolled liver damage. The safety of any new curative therapies should be measured in relation to the excellent safety of currently approved nucleos(t)ide analogues. Development of novel antiviral and immune modulatory therapies should be associated with new diagnostic assays used to evaluate the effectiveness or to predict response.

Immune response induced by recombinant pres2/S-protein and a pres2-S-protein fused with a core 18-27 antigen fragment of hepatitis B virus compared to conventional HBV vaccine

Although comprehensive vaccination is the cornerstone of public health programs to control hepatitis B virus (HBV) infections, 5% of people who receive the existing vaccine do not develop proper immunity against HBV. To overcome this challenge, researchers have tried using various protein fragments encoded by the virus genome to achieve better immunization rates. An important antigenic component of HBsAg called the preS2/S or M protein has also received much attention in this area. The gene sequences of preS2/S and Core18-27 peptide were extracted from the GenBank (NCBI). Final gene synthesis was conducted with pET28. Groups of BALB/c mice were immunized with 10 μg/ml of recombinant proteins and 1 μg/ml CPG7909 adjuvant. Serum levels of IF-γ, TNF-α, IL-2, IL-4, and IL-10 were measured by ELISA assay method on spleen cell cultures on day 45, and IgG1, IgG2a, and total IgG titers obtained from mice serum were quantified on days 14 and 45. Statistical analysis did not show any significant difference between the groups regarding IF-γ level. There were, however, significant differences in terms of IL-2 and IL-4 levels between the groups receiving preS2/S-C18-27 with and without adjuvant and the groups receiving both preS2/S and preS2/S-C18-27 (Plus Recomb-Plus Recomb: the group of mice that received both preS2/S and preS2/S-C18-27 simultaneously). The strongest total antibody production was induced by immunization with both recombinant proteins without CPG adjuvant. The groups that received both preS2/S and preS2/S-C18-27, whether with or without adjuvant, were significantly different from those that received the conventional vaccine considering most abundant interleukins. This difference suggested that higher levels of efficacy can be achieved by the use of multiple virus antigen fragments rather than using a single fragment.

miR-548c-3p targets TRIM22 to attenuate the Peg–IFN–α therapeutic efficacy in HBeAg-positive patients with chronic hepatitis B

Chronic hepatitis B (CHB) patients treated with interferon shows encouraging results. However, its clinical efficacy is limited by significant individual differences in treatment responses. We identified an interferon-inducible effector, TRIM22, as the likely causal target of such differential responses. We found that TRIM22 was highly expressed in interferon-responsive patients and negatively correlated with HBV DNA and HBeAg serum levels. Stable cells overexpressing TRIM22 carried significantly less HBsAg, HBeAg, and HBV DNA, and cells with knocked-down TRIM22 by shRNA displayed higher levels of these markers than controls. Integrated bioinformatics analysis and subsequent experiments revealed that TRIM22 overexpression significantly increased the supernatant levels of IL-1β and IL-8, two important cytokines of NOD2/NF-κB pathway involved in interferon-induced antiviral activities. We identified three candidate microRNAs binding to 3'UTR of TRIM22 at various locations through typical imperfect paring using the TargetScan program. MiR-548c-3p appeared to be highly expressed, while the TRIM22 level was low in the suboptimal response group of CHB patients. The Luciferase reporter assay revealed an interaction between miR-548c-3p and the 3'UTR of TRIM22, leading to a controlled suppression of TRIM22 endogenous expression. This resulted in interferon's substantially weakened therapeutic efficacy, as indicated by the elevation of the serum levels of HBsAg, HBeAg and HBV DNA in miR-548c-3p-transfected HepAD38 cells. Our study demonstrated that a particular miR-548c-3p is the key negative regulator of TRIM22 in CHB patients with a weak response to interferon treatment, providing a novel marker and target in interferon-α therapy evaluation.

Serum cytokine change profile associated with HBsAg loss during combination therapy with PEG-IFN-α in NAs-suppressed chronic hepatitis B patients

Objective

The aim of this study was to explore the profile of cytokine changes during the combination therapy with pegylated interferon alpha (PEG-IFN-α) and its relationship with HBsAg loss in nucleos(t)ide analogs (NAs)-suppressed chronic hepatitis B patients.

Methods

Seventy-six patients with chronic hepatitis B with HBsAg less than 1,500 IU/ml and HBV DNA negative after receiving ≥ 1-year NAs therapy were enrolled. Eighteen patients continued to take NAs monotherapy (the NAs group), and 58 patients received combination therapy with NAs and PEG-IFN-α (the Add-on group). The levels of IFNG, IL1B, IL1RN, IL2, IL4, IL6, IL10, IL12A, IL17A, CCL2, CCL3, CCL5, CXCL8, CXCL10, TNF, and CSF2 in peripheral blood during treatment were detected.

Results

At week 48, 0.00% (0/18) in the NAs group and 25.86% (15/58) in the Add-on group achieved HBsAg loss. During 48 weeks of combined treatment, there was a transitory increase in the levels of ALT, IL1RN, IL2, and CCL2. Compared to the NAs group, CXCL8 and CXCL10 in the Add-on group remain higher after rising, yet CCL3 showed a continuously increasing trend. Mild and early increases in IL1B, CCL3, IL17A, IL2, IL4, IL6, and CXCL8 were associated with HBsAg loss or decrease >1 log, while sustained high levels of CCL5 and CXCL10 were associated with poor responses to Add-on therapy at week 48.

Conclusions

The serum cytokine change profile is closely related to the response to the combination therapy with PEG-IFN-α and NAs, and may help to reveal the mechanism of functional cure and discover new immunological predictors and new therapeutic targets.

Profiling of Peripheral TRBV and CD4+CD25+ Treg in CHB Patients with HBeAg SC during TDF Treatment

BACKGROUND

It is lacking that markers could predict the prognosis of chronic hepatitis B (CHB) subjects during antiviral treatment, and the related cellular immune mechanism is not fully evaluated.

AIM

To explore the comprehensive profile of T cell receptor β-chain (TRBV) and CD4+CD25+ regulatory T cell (Treg) in peripheral blood of CHB patients with HBeAg seroconverting (SC) during tenofovir disoproxil fumarate (TDF) treatment.

METHODS

The frequency of CD4+CD25high+ Treg and number of skewed TRBV in 20 HBeAg positive patients were determined at baseline and following every 12 weeks during 96-week TDF treatment. The relationship among serum alanine aminotransferase (ALT) level, HBV DNA load, Treg frequency, and the number of skewed TRBV, respectively, was analyzed for CHB patients. Receiver operative characteristic curve was applied to analyze their diagnostic value for HBeAg SC.

RESULTS

The number of skewed TRBV at week 48, Treg frequency at week 72, and ALT level at baseline could predict the HBeAg SC or non-SC in CHB patients during 96-week TDF treatment. Moreover, the positive correlation between ALT or HBV DNA and Treg levels or skewed TRBVs was significant in the SC group, but not in non-SC.

CONCLUSIONS

The predictive cutoff value of ALT for HBeAg SC was 178 U/L at baseline. Moreover, the ALT, Treg, and TRBV families would be associated with the prognosis and pathogenesis of CHB patients during TDF treatment.

MiR181-5p promotes pathogenic angiogenesis of hepatopulmonary syndrome by negatively regulating Wnt inhibitor Wif1

Objectives

Hepatopulmonary syndrome is a serious respiratory injury caused by chronic liver disease. Excessive pulmonary capillary angiogenesis is the key pathological event. However, the mechanism of microRNA regulatory pulmonary capillary angiogenesis is still unclear.

Materials and Methods

The hepatopulmonary syndrome rat model was constructed by Common bile duct ligation (CBDL) surgery. The expression tread of miR181-5p and Wif1 was detected by qRT-PCR and western blot in various tissues and disease processes. Wif1 was predicted as one of the potential target genes of miR181-5p by bioinformatic assay. miR181-5p mimics and inhibitors were used to increase/decrease miR181-5p levels in pulmonary microvascular cells. And Wif-1 specific recombinant lentiviruses were used to up-regulate and down-regulate Wif1 in pulmonary microvascular cells. Then, CCK8, Transwell, and tube formation assay were used for pulmonary microvascular cell proliferation, migration, and tube formation. And Dual-luciferase reporter assay was used to assess that miR181-5p may direct regulate Wif-1 in HPS rats.

Results

The result showed miR181-5p specifically activates the Wnt signaling pathway by inhibiting Wif1 and then promotes pulmonary microvascular cell proliferation, migration, and tube formation, thereby accelerating the process of HPS. We finally verified Wif1 as a novel and direct target of miR181-5p in HPS.

Conclusion

Taken together, we revealed an important miR-181-5p/Wif1/Wnt pathway in regulating pathological angiogenesis. It will prove beneficial as a therapeutic strategy for hepatopulmonary syndrome.

Dynamic comparison of early immune reactions and immune cell reconstitution after umbilical cord blood transplantation and peripheral blood stem cell transplantation

Umbilical cord blood transplantation (UCBT) and peripheral blood stem cell transplantation (PBSCT) are effective allogeneic treatments for patients with malignant and non-malignant refractory hematological diseases. However, the differences in the immune cell reconstitution and the immune reactions during initial stages post-transplantation are not well established between UCBT and PBSCT. Therefore, in this study, we analyzed the differences in the immune reactions during the early stages (days 7-100 post-transplantation) such as pre-engraftment syndrome (PES), engraftment syndrome (ES), and acute graft-versus-host disease (aGVHD) and the immune cell reconstitution between the UCBT and the PBSCT group of patients. We enrolled a cohort of patients that underwent UCBT or PBSCT and healthy controls (n=25 each) and evaluated their peripheral blood mononuclear cell (PBMC) samples and plasma cytokine (IL-10 and GM-CSF) levels using flow cytometry and ELISA, respectively. Our results showed that the incidences of early immune reactions such as PES, ES, and aGVHD were significantly higher in the UCBT group compared to the PBSCT group. Furthermore, in comparison with the PBSCT group, the UCBT group showed higher proportion and numbers of naïve CD4⁺ T cells, lower proportion and numbers of Tregs, higher proportion of CD8⁺ T cells with increased activity, and higher proportion of mature CD56^dim CD16⁺ NK cells during the early stages post-transplantation. Moreover, the plasma levels of GM-CSF were significantly higher in the UCBT group compared to the PBSCT group in the third week after transplantation. Overall, our findings demonstrated significant differences in the post-transplantation immune cell reconstitution between the UCBT and the PBSCT group of patients. These characteristics were associated with significant differences between the UCBT and the PBSCT groups regarding the incidences of immune reactions during the early stages post transplantation.

Abnormally primed CD8 T cells: The Achilles' heel of CHB

Chronic hepatitis B virus (HBV) infection continues to be a significant public health challenge, and more than 250 million people around world are infected with HBV. The clearance of HBV with virus-specific CD8 T cells is critical for a functional cure. However, naïve HBV-specific CD8 T cells are heavily hindered during the priming process, and this phenomenon is closely related to abnormal cell and signal interactions in the complex immune microenvironment. Here, we briefly summarize the recent progress in understanding the abnormal priming of HBV-specific CD8 T cells and some corresponding immunotherapies to facilitate their functional recovery, which provides a novel perspective for the design and development of immunotherapy for chronic HBV infection (CHB). Finally, we also highlight the balance between viral clearance and pathological liver injury induced by CD8 T-cell activation that should be carefully considered during drug development.

GARP-mediated active TGF-β1 induces bone marrow NK cell dysfunction in AML patients with early relapse post-allo-HSCT

Relapse is a leading cause of death after allogeneic hematopoietic stem cell transplantation (allo-HSCT) for acute myeloid leukemia (AML). However, the underlying mechanisms remain poorly understood. Natural killer (NK) cells play a crucial role in tumor surveillance and cancer immunotherapy, and NK cell dysfunction has been observed in various tumors. Here, we performed ex vivo experiments to systematically characterize the mechanisms underlying the dysfunction of bone marrow-derived NK (BMNK) cells isolated from AML patients experiencing early relapse after allo-HSCT. We demonstrated that higher levels of active transforming growth factor β1 (TGF-β1) were associated with impaired effector function of BMNK cells in these AML patients. TGF-β1 activation was induced by the overexpression of glycoprotein A repetitions predominant on the surface of CD4+ T cells. Active TGF-β1 significantly suppressed mTORC1 activity, mitochondrial oxidative phosphorylation, the proliferation, and cytotoxicity of BMNK cells. Furthermore, pretreatment with the clinical stage TGF-β1 pathway inhibitor, galunisertib, significantly restored mTORC1 activity, mitochondrial homeostasis, and cytotoxicity. Importantly, the blockade of the TGF-β1 signaling improved the antitumor activity of NK cells in a leukemia xenograft mouse model. Thus, our findings reveal a mechanism explaining BMNK cell dysfunction and suggest that targeted inhibition of TGF-β1 signaling may represent a potential therapeutic intervention to improve outcomes in AML patients undergoing allo-HSCT or NK cell-based immunotherapy.

Hepatitis B functional cure and immune response

Hepatitis B virus (HBV) is a hepatotropic virus, which damage to hepatocytes is not direct, but through the immune system. HBV specific CD4+ T cells can induce HBV specific B cells and CD8+ T cells. HBV specific B cells produce antibodies to control HBV infection, while HBV specific CD8+ T cells destroy infected hepatocytes. One of the reasons for the chronicity of HBV infection is that it cannot effectively activate adoptive immunity and the function of virus specific immune cells is exhausted. Among them, virus antigens (including HBV surface antigen, e antigen, core antigen, etc.) can inhibit the function of immune cells and induce immune tolerance. Long term nucleos(t)ide analogues (NAs) treatment and inactive HBsAg carriers with low HBsAg level may "wake up" immune cells with abnormal function due to the decrease of viral antigen level in blood and liver, and the specific immune function of HBV will recover to a certain extent, thus becoming the "dominant population" for functional cure. In turn, the functional cure will further promote the recovery of HBV specific immune function, which is also the theoretical basis for complete cure of hepatitis B. In the future, the complete cure of chronic HBV infection must be the combination of three drugs: inhibiting virus replication, reducing surface antigen levels and specific immune regulation, among which specific immunotherapy is indispensable. Here we review the relationship, mechanism and clinical significance between the cure of hepatitis B and immune system.

Interleukin-2 promotes pegylated interferon alpha for hepatitis B surface antigen loss: A retrospective pragmatic clinical study at the Fourth Affiliated Hospital of Zhejiang University Medical College

Background and Aims

Interleukin-2 (IL-2) can be used as an adjuvant therapy when pegylated interferon alpha (Peg-IFN-α) does not effectively promote hepatitis B surface antigen (HBsAg) loss, but the relevant timing, kinetic patterns, and prognostic associations of this intervention are unclear.

Methods

A total of 115 patients with chronic hepatitis B (CHB) treated at our institution between October 2018 and March 2021 were included in this retrospective analysis. They were divided into two kinetic patterns by using K-medoids cluster analysis. Profile and prognostic associations were statistically analyzed between the two patterns.

Results

After baseline standardization, before the intervention, the relative HBsAg level showed a continuously increasing trend, but after the intervention, it showed a continuously decreasing trend. Based on the relative change in the HBsAg level, two kinetic patterns, namely, a fluctuation platform pattern and a stepwise growth pattern, were identified by using K-medoids cluster analysis for all 115 patients before IL-2 intervention. Profile analysis showed that there were statistically significant differences between the two patterns before IL-2 intervention (p < 0.05), but their profiles showed the same trend after 2 weeks of IL-2 intervention. Prognostic association analysis showed that CD8+ T cells, alanine transaminase (ALT), age, natural killer (NK) cells, neutrophils, and course of treatment before IL-2 intervention were the six main indicators affecting the relative decrease in the HBsAg level.

Conclusion

For CHB patients who have received continuous Peg-IFN-α treatment, IL-2 intervention should be given as early as possible when the HBsAg level has not decreased for four consecutive weeks or a fluctuation platform pattern is observed. After the intervention, a downward relative change in the HBsAg level can be maintained over 4 weeks. CD8+ T cells, ALT, NK cells, and neutrophils are baseline indicators closely related to the prognosis of this intervention.

Cytomegalovirus-specific neutralizing antibodies effectively prevent uncontrolled infection after allogeneic hematopoietic stem cell transplantation

Cytomegalovirus (CMV) infection remains one of the most frequent and life-threatening infectious complications after allogeneic hematopoietic stem cell transplantation (allo-HSCT). Herein, we comprehensively compared the immune cells of patients with uncontrolled and controlled CMV infection post-allo-HSCT and found that B-cells were extraordinarily insufficient because of impaired B-cells reconstitution in the uncontrolled infection group. Furthermore, in the controlled infection group, reconstructed B-cells showed signatures of mature B-cells, high expression of CXCR4 and IFITM1, and enrichment of CMV-associated B-cell receptors, which were lacking in the uncontrolled infection group. Consistently, sera from the uncontrolled infection group failed to inhibit CMV infection via neutralizing virus in vitro because of its lower content of anti-CMV-specific immunoglobulin G (IgG) than the controlled infection group. Overall, these results highlighted the contribution of B cells and anti-CMV-specific neutralizing IgGs to the restraint of CMV infection post-allo-HSCT, suggesting their potential as a supplementary treatment to improve outcomes.

Advances in Immunotherapy for Hepatitis B

Hepatitis B virus (HBV) is a hepatotropic virus with the potential to cause chronic infection, and it is one of the common causes of liver disease worldwide. Chronic HBV infection leads to liver cirrhosis and, ultimately, hepatocellular carcinoma (HCC). The persistence of covalently closed circular DNA (cccDNA) and the impaired immune response in patients with chronic hepatitis B (CHB) has been studied over the past few decades. Despite advances in the etiology of HBV and the development of potent virus-suppressing regimens, a cure for HBV has not been found. Both the innate and adaptive branches of immunity contribute to viral eradication. However, immune exhaustion and evasion have been demonstrated during CHB infection, although our understanding of the mechanism is still evolving. Recently, the successful use of an antiviral drug for hepatitis C has greatly encouraged the search for a cure for hepatitis B, which likely requires an approach focused on improving the antiviral immune response. In this review, we discuss our current knowledge of the immunopathogenic mechanisms and immunobiology of HBV infection. In addition, we touch upon why the existing therapeutic approaches may not achieve the goal of a functional cure. We also propose how combinations of new drugs, and especially novel immunotherapies, contribute to HBV clearance.

Low-dose IL-2 therapy limits the reduction in absolute numbers of peripheral lymphocytes in systemic lupus erythematosus patients with infection

BACKGROUND

Systemic lupus erythematosus (SLE) is a heterogeneous autoimmune disorder characterized by disturbed cellular and humoral immune responses. Dysregulations of immune system and immunosuppressive medications predispose SLE patients to infection. This study aims to investigate the alterations and absolute concentrations of lymphocyte subpopulations in SLE patients with different infection and their responses of low-dose IL-2 therapy.

METHODS

A total of 333 patients with SLE without recent infection, 162 patients suffering infection, and age and sex-matched 132 healthy controls (HCs) were recruited. Of them, 54 SLE patients (including 41 non-infected group and 13 infected group) received a 5-day course of low-dose IL-2 administration at a dose of 0.5 million IU per day. Lymphocyte subpopulations were analyzed by flow cytometry.

RESULTS

Patients with SLE had lower levels of lymphocyte subpopulations in peripheral blood such as T, B, NK, CD4 + T, CD8+ T, Th1, Th2, Th17, and Treg cells, and the reduction in these cells was more obvious in patients with infection (p <.05 to p <.01). Low-dose IL-2 effectively expanded T (p <.001), B (p <.001), CD4 + T (p <.01), CD8 + T (p <.001), Th1 (p <.01), Th17 (p <.1), and Treg cells (p <.01) of SLE patients, these cells were comparable to that of HCs after the IL-2 treatment.

CONCLUSIONS

Patients with SLE had insufficiency of circulating lymphocyte subsets. This phenomenon was more obverse in those accompanying infection, suggesting the low concentration of lymphocytes may be used as indicators of high infection risk in SLE patients. Low-dose IL-2 induced expansion of Treg cells and NK cells, which may contribute to the restoration of immune homeostasis in SLE patients.

Immunologic Gene Sets Reveal Features of the Tumor Immune Microenvironment and Predict Prognosis and Immunotherapy Response: A Pan-Cancer Analysis

In the treatment of cancer, anti-programmed cell death-1 (PD-1)/programmed cell death-ligand 1 (PD-L1) immunotherapy has achieved unprecedented clinical success. However, the significant response to these therapies is limited to a small number of patients. This study aimed to predict immunotherapy response and prognosis using immunologic gene sets (IGSs). The enrichment scores of 4,872 IGSs in 348 patients with metastatic urothelial cancer treated with anti-PD-L1 therapy were computed using gene set variation analysis (GSVA). An IGS-based classification (IGSC) was constructed using a nonnegative matrix factorization (NMF) approach. An IGS-based risk prediction model (RPM) was developed using the least absolute shrinkage and selection operator (LASSO) method. The IMvigor210 cohort was divided into three distinct subtypes, among which subtype 2 had the best prognosis and the highest immunotherapy response rate. Subtype 2 also had significantly higher PD-L1 expression, a higher proportion of the immune-inflamed phenotype, and a higher tumor mutational burden (TMB). An RPM was constructed using four gene sets, and it could effectively predict prognosis and immunotherapy response in patients receiving anti-PD-L1 immunotherapy. Pan-cancer analyses also demonstrated that the RPM was capable of accurate risk stratification across multiple cancer types, and RPM score was significantly associated with TMB, microsatellite instability (MSI), CD8+ T-cell infiltration, and the expression of cytokines interferon-γ (IFN-γ), transforming growth factor-β (TGF-β) and tumor necrosis factor-α (TNF-α), which are key predictors of immunotherapy response. The IGSC strengthens our understanding of the diverse biological processes in tumor immune microenvironment, and the RPM can be a promising biomarker for predicting the prognosis and response in cancer immunotherapy.

Application of double-negative T cells in haematological malignancies: recent progress and future directions

Haematologic malignancies account for a large proportion of cancers worldwide. The high occurrence and mortality of haematologic malignancies create a heavy social burden. Allogeneic haematopoietic stem cell transplantation is widely used in the treatment of haematologic malignancies. However, graft-versus-host disease and relapse after allogeneic haematopoietic stem cell transplantation are inevitable. An emerging treatment method, adoptive cellular therapy, has been effectively used in the treatment of haematologic malignancies. T cells, natural killer (NK) cells and tumour-infiltrating lymphocytes (TILs) all have great potential in therapeutic applications, and chimeric antigen receptor T (CAR-T) cell therapy especially has potential, but cytokine release syndrome and off-target effects are common. Efficient anticancer measures are urgently needed. In recent years, double-negative T cells (CD3⁺CD4^-CD8^-) have been found to have great potential in preventing allograft/xenograft rejection and inhibiting graft-versus-host disease. They also have substantial ability to kill various cell lines derived from haematologic malignancies in an MHC-unrestricted manner. In addition, healthy donor expanded double-negative T cells retain their antitumour abilities and ability to inhibit graft-versus-host disease after cryopreservation under good manufacturing practice (GMP) conditions, indicating that double-negative T cells may be able to be used as an off-the-shelf product. In this review, we shed light on the potential therapeutic ability of double-negative T cells in treating haematologic malignancies. We hope to exploit these cells as a novel therapy for haematologic malignancies.