Comparison of the different anti-CD16 antibody clones in the activation and expansion of peripheral blood NK cells.

Natural killer (NK) cells are promising tool for cancer treatment. Methods have been developed for large-scale NK cell expansion, including feeder cell-based methods or methods involving stimulation with NK cell activating signals, such as anti-CD16 antibodies. Different clones of anti-CD16 antibodies are available; however, a comprehensive comparison of their differential effects on inducing NK cell activation and expansion has not been conducted among these various clones under the same experimental conditions.

Expanded natural killer cells potentiate the antimyeloma activity of daratumumab, lenalidomide, and dexamethasone in a myeloma xenograft model.

The development of new treatment agents in recent decades has significantly improved the survival of patients with multiple myeloma (MM). Nonetheless, MM remains an incurable disease; therefore, novel combination therapies are required. Natural killer (NK) cells are one of the safest immunotherapeutic options.

Selective Expansion of NKG2C+ Adaptive NK Cells Using K562 Cells Expressing HLA-E.

Adaptive natural killer (NK) cells expressing self-specific inhibitory killer-cell immunoglobulin-like receptors (KIRs) can be expanded in vivo in response to human cytomegalovirus (HCMV) infection. Developing a method to preferentially expand this subset is essential for effective targeting of allogeneic cancer cells. A previous study developed an in vitro method to generate single KIR+ NK cells for enhanced targeting of the primary acute lymphoblastic leukemia cells; however, the expansion rate was quite low.

Application of Blood Group Genotyping by Next-Generation Sequencing in Various Immunohaematology Cases.

Background: Next-generation sequencing (NGS) technology has been recently introduced into blood group genotyping; however, there are few studies using NGS-based blood group genotyping in real-world clinical settings. In this study, we applied NGS-based blood group genotyping into various immunohaematology cases encountered in routine clinical practice.

Methods: This study included 4 immunohaematology cases: ABO subgroup, ABO chimerism, antibody to a high-frequency antigen (HFA), and anti-CD47 interference.

Expansion of cytotoxic natural killer cells in multiple myeloma patients using K562 cells expressing OX40 ligand and membrane-bound IL-18 and IL-21.

Background: Natural killer (NK) cell-based immunotherapy is a promising treatment approach for multiple myeloma (MM), but obtaining a sufficient number of activated NK cells remains challenging. Here, we report an improved method to generate ex vivo expanded NK (eNK) cells from MM patients based on genetic engineering of K562 cells to express OX40 ligand and membrane-bound (mb) IL-18 and IL-21.

Methods: K562-OX40L-mbIL-18/-21 cells were generated by transducing K562-OX40L cells with a lentiviral vector encoding mbIL-18 and mbIL-21, and these were used as feeder cells to expand NK cells from peripheral blood mononuclear cells of healthy donors (HDs) and MM patients in the presence of IL-2/IL-15.

Double-filtered leukoreduction as a method for risk reduction of transfusion-associated graft-versus-host disease.

Background: Transfusion-associated graft-versus-host disease (TA-GvHD) is caused by leukocytes, specifically T cells within a transfused blood product. Currently, the prevention of transfusion-associated graft-versus-host disease is performed by irradiation of blood products. With a sufficient reduction of leukocytes, the risk for TA-GvHD can be decreased.

Expansion of Human NK Cells Using K562 Cells Expressing OX40 Ligand and Short Exposure to IL-21.

Natural Killer (NK) cell-based immunotherapy used to treat cancer requires the adoptive transfer of a large number of activated NK cells. Here, we report a new effective method to expand human NK cells using K562 cells genetically engineered (GE) to express OX40 ligand (K562-OX40L) in combination with a short exposure to soluble IL-21. In addition, we describe a possible mechanism of the NK cell expansion through the OX40 receptor-OX40 ligand axis which is dependent on NK cell homotypic interaction.

X-ray as Irradiation Alternative for K562 Feeder Cell Inactivation in Human Natural Killer Cell Expansion.

Background/aim: γ-Irradiation has been proven to be the most effective method to inactivate K562 cells, but γ-irradiators are not available in some institutes. This study was designed to compare the effects of X-ray and γ-irradiation on K562 cells in natural killer (NK) cell expansion.

Materials And Methods: To expand NK cells, isolated peripheral blood mononuclear cells (PBMCs) were co-cultured with γ-irradiated or X-ray-treated K562 cells plus IL-2 and IL-15.

The first case of congenital blood chimerism in two of the triplets in Korea.

Background: Chimeras are composed of two or more different populations that originated from different zygotes. Blood chimerism arising from twins have been reported in the literature. Herein, we report the first blood group chimerism in triplets.

The Allele (c.280A>T) Is Responsible for the Weak A Phenotype.

The allele was found in a 71-year-old Korean male with ABO discrepancy and in his two sons. Although the allele (c.280A>T, I94F) in an AwB case was registered in GenBank, the impact of the I94F mutation of the ABO gene on the activity of A transferase has not been studied.

Natural killer cell subsets and receptor expression in peripheral blood mononuclear cells of a healthy Korean population: Reference range, influence of age and sex, and correlation between NK cell receptors and cytotoxicity.

Background: The purpose of this study was to identify CD56 and CD56 natural killer (NK) cell subsets and analyze their receptors expression in a healthy Korean population, and to determine whether receptor expression correlates with age, sex, and cytotoxicity.

Materials And Methods: We performed multicolor flow cytometry assays to analyze the expression of various NK cell receptors (CD16, NKG2A, NKG2C, NKG2D, CD57, DNAM-1, CD8a, CD62L, NKp30, and NKp46) on both CD3/CD56 and CD3/CD56 NK cells in whole-blood samples from 122 healthy donors. The expression of these receptors was compared according to age (<30years, n=22, 30-60years, n=73 and >60years, n=27) and gender (male, n=61, female, n=61).

Irradiation of breast cancer cells enhances CXCL16 ligand expression and induces the migration of natural killer cells expressing the CXCR6 receptor.

Background Aims: Few studies have examined the migration pattern of natural killer (NK) cells, especially after radiation treatment for cancer. We investigated whether irradiation can modulate the expression of chemokines in cancer cells and the migration of NK cells to irradiated tumor cells.

Methods: The expression of chemokine receptors (CXCR3, CXCR4 and CXCR6) on interleukin-2 (IL-2)/IL-15-activated NK cells was assessed using flow cytometry.

Seasonality of hospital admissions for mental disorders in Hanoi, Vietnam.

Background: Some studies have shown a relationship between seasonality in weather patterns and depressive and behavioural disorders, especially in temperate climate regions. However, there is a lack of studies describing the seasonal patterns of hospital admissions for a variety of mental disorders in tropical and subtropical nations. The aim of this study has been to examine the relationship between seasons and daily hospital admissions for mental disorders in Hanoi, Vietnam.

Heatwaves and Hospital Admissions for Mental Disorders in Northern Vietnam.

Studies in high-income countries have shown an association between heatwaves and hospital admissions for mental disorders. It is unknown whether such associations exist in subtropical nations like Vietnam. The study aim was to investigate whether hospital admissions for mental disorders may be triggered, or exacerbated, by heat exposure and heatwaves, in a low- and middle-income country, Vietnam.

Expansion of NK Cells Using Genetically Engineered K562 Feeder Cells.

Natural killer (NK) cells can be expanded upon activation by proliferative cytokines (such as IL-2 and IL-15). The NK cell expansion can be greatly enhanced by proteins from feeder cells such as tumor cell lines or PBMCs. Therefore, coculture systems of irradiated feeder cells and NK cells in media containing IL-2 and IL-15 have been developed to generate large numbers of NK cells, although NK cell expansion protocol using anti-CD3 antibody (OKT-3) without feeder cells has also been developed.

Comparison of FcRγ-Deficient and CD57+ Natural Killer Cells Between Cord Blood and Adult Blood in the Cytomegalovirus-Endemic Korean Population.

Background: FcRγ-deficient natural killer (NK) cells (g(-)NK cells) have been associated with cytomegalovirus (CMV) infection. However, the frequency of g(-)NK cells in a CMV-endemic area (i.e.