CD38+CD39+ NK cells associate with HIV disease progression and negatively regulate T cell proliferation

Lymphocyte profile in peripheral blood of patients with multiple myeloma

Multiple myeloma (MM) is a disease which remains incurable. One of the main reasons is a weakened immune system that allows MM cells to survive. Therefore, the current research is focused on the study of immune system imbalance in MM to find the most effective immunotherapy strategies. Aiming to identify the key points of immune failure in MM patients, we analysed peripheral lymphocytes subsets from MM patients (n = 57) at various stages of the disease course and healthy individuals (HI, n = 15) focusing on T, NK, iNKT, B cells and NK-cell cytokines. Our analysis revealed that MM patients exhibited immune alterations in all studied immune subsets. Compared to HI, MM patients had a significantly lower proportion of CD4 + T cells (19.55% vs. 40.85%; p < 0.001) and CD4 + iNKT cells (18.8% vs. 40%; p < 0.001), within B cells an increased proportion of CD21LCD38L subset (4.5% vs. 0.4%; p < 0.01) and decreased level of memory cells (unswitched 6.1% vs. 14.7%; p < 0.001 and switched 7.8% vs. 11.2%; NS), NK cells displaying signs of activation and exhaustion characterised by a more than 2-fold increase in SLAMF7 MFI (p < 0.001), decreased expression of NKG2D (MFI) and NKp46 (%) on CD16 + 56 + and CD16 + 56- subset respectively (p < 0.05), Effective immunotherapy needs to consider these immune defects and monitoring of the immune status of MM patients is essential to define better interventions in the future.

A comprehensive review on targeting cluster of differentiation: An attractive strategy for inhibiting viruses through host proteins

Viral infections continue to pose a significant global public health threat. Targeting host proteins, such as cluster of differentiation (CD) macromolecules, may offer a promising alternative approach to developing antiviral treatments. CDs are cell-surface biological macromolecules mainly expressed on leukocytes that viruses can use to enter cells, thereby evading immune detection and promoting their replication. The manipulation of CDs by viruses may represent an effective and clever means of survival through the prolonged co-evolution of hosts and viruses. Targeting of CDs is anticipated to hinder the invasion of related viruses, modulate the body's immune system, and diminish the incidence of subsequent inflammation. They have become crucial for biomedical diagnosis, and some have been used as valuable tools for resisting viral infections. However, a summary of the structures and functions of CDs involved in viral infection is currently lacking. The development of drugs targeting these biological macromolecules is restricted both in terms of their availability and the number of compounds currently identified. This review provides a comprehensive analysis of the critical role of CD proteins in virus invasion and a list of relevant targeted antiviral agents, which will serve as a valuable reference for future research in this field.

[ARL67156, a small-molecule CD39 inhibitor, enhances natural killer cell cytotoxicity against gastric cancer cells in vitro and in nude mice]

OBJECTIVE

To investigate the effect of ARL67156, a small-molecule inhibitor of CD39, on cytotoxicity of natural killer (NK) cells against gastric cancer cells.

METHODS

Human peripheral blood-derived primary NK cells isolated and purified using a magnetic bead antibody method were treated with 100 μmol/L ARL67156 for 24 h, and the signaling pathway of NK cell activation was detected by Western blotting. The level of interferon-γ (IFN-γ) in the supernatant of NK cells co-cultured with gastric cancer cells was detected using ELISA, and NK cell CD107a degranulation was measured with flow cytometry. The cytotoxicity of NK cells against co-cultured gastric cancer cells was evaluated using flow cytometry. In a nude mouse model bearing subcutaneous gastric cancer xenografts, the therapeutic effect of intravenous transfusion of NK cells and intraperitoneal injection of ARL67156 was assessed by measuring the changes in tumor volume.

RESULTS

(25.97 ± 5.69) % of peripheral blood NK cells from healthy individuals positive for CD39 expression. Treatment with ARL67156 significantly upregulated the activation molecules including NKG2D, DAP10, CD57, and CD16 and reduced the expressions of the inhibitory receptors TIGIT and KIR, thereby promoting the secretion of IFN-γ and CD107a degranulation in NK cells (P < 0.05). In both the in vitro and in vivo experiments, ARL67156 significantly enhanced the cytotoxicity of NK cells against gastric cancer cells (P < 0.05).

CONCLUSION

ARL67156 activates NK cells through the vav1-Syk signaling pathway to enhance their cytotoxicity against gastric cancer cells, which may serve as a new strategy for NK cell immunotherapy for gastric cancer.

The Role of Cluster of Differentiation 39 (CD39) and Purinergic Signaling Pathway in Viral Infections

CD39 is a marker of immune cells such as lymphocytes and monocytes. The CD39/CD73 pathway hydrolyzes ATP into adenosine, which has a potent immunosuppressive effect. CD39 regulates the function of a variety of immunologic cells through the purinergic signaling pathways. CD39+ T cells have been implicated in viral infections, including Human Immunodeficiency Virus (HIV), Cytomegalovirus (CMV), viral hepatitis, and Corona Virus Disease 2019 (COVID-19) infections. The expression of CD39 is an indicator of lymphocyte exhaustion, which develops during chronicity. During RNA viral infections, the CD39 marker can profile the populations of CD4+ T lymphocytes into two populations, T-effector lymphocytes, and T-regulatory lymphocytes, where CD39 is predominantly expressed on the T-regulatory cells. The level of CD39 in T lymphocytes can predict the disease progression, antiviral immune responses, and the response to antiviral drugs. Besides, the percentage of CD39 and CD73 in B lymphocytes and monocytes can affect the status of viral infections. In this review, we investigate the impact of CD39 and CD39-expressing cells on viral infections and how the frequency and percentage of CD39+ immunologic cells determine disease prognosis.