Natural Killer Cells In Patients Research Articles

Changes in subset distribution and impaired function of circulating natural killer cells in patients with colorectal cancer

Natural killer (NK) cells are closely associated with malignant tumor progression and metastasis. However, studies on their relevance in colorectal cancer (CRC) are limited. We aimed to comprehensively analyze the absolute counts, phenotypes, and function of circulating NK cells in patients with CRC using multiparametric flow cytometry. The distribution of NK cell subsets in the peripheral circulation of patients with CRC was significantly altered relative to the control group. This is shown by the decreased frequency and absolute count of CD56dimCD16+ NK cells with antitumor effects, contrary to the increased frequency of CD56bright NK and CD56dimCD16- NK cells with poor or ineffective antitumor effects. NK cells in patients with CRC were functionally impaired, with decreased intracellular interferon (IFN)-γ secretion and a significantly lower percentage of cell surface granzyme B and perforin expression. In addition, IFN-γ expression decreased significantly with the tumor stage progression. Based on a comprehensive analysis of the absolute counts, phenotypes, and functional markers of NK cells, we found an altered subset distribution and impaired function of circulating NK cells in patients with CRC.

Immunoglobulin-like transcript 2 as an impaired anti-tumor cytotoxicity marker of natural killer cells in patients with hepatocellular carcinoma.

Natural killer (NK) cells play a pivotal role in immune surveillance in the liver. We aimed to identify potential targets for NK cell-mediated immune intervention by revealing the functional molecules on NK cells in HCC patients. To evaluate the impact of aging on NK cell phenotypes, we examined NK cells from healthy volunteers (HVs) of various ages. Because ILT2 expression on CD56dim NK cells increased with increasing age, we enrolled age-matched HCC patients and HVs. We determined the NK cell phenotypes in blood mononuclear cells (PBMCs) and intrahepatic lymphocytes (IHLs) from cancerous and non-cancerous tissues. We evaluated cytotoxicity and antibody-dependent cellular cytotoxicity (ADCC) of NK cells in vitro. ILT2-positive CD56dim NK cells in PBMCs were increased in HCC patients compared with HVs. In HCC patients, ILT2-positive CD56dim NK cells were increased in cancerous IHLs compared with non-cancerous IHLs and PBMCs. We examined the impact of macrophage migration inhibitory factor (MIF) on ILT2 expression in co-cultures of HCC cells and NK cells. The enhanced expression of ILT2 on CD56dim NK cells from HCC patients was inhibited by masking antibodies against MIF and CXCR4. ILT2-positive CD56dim NK cells exhibited lower capacities for cytotoxicity and ADCC than ILT2-negative cells, which were partially restored by ILT2 blockade. In HCC patients, ILT2 is a signature molecule for cancerous CD56dim NK cells with impaired cytolytic capacity. The MIF-CXCR4 interaction is associated with ILT2 induction on CD56dim NK cells and ILT2 serves as a target for functional NK cell restoration.

Effect of camelid B7-H3 tri-specific killer engagers on natural killer cells in patients with prostate cancer.

155 Background: Recombinant human (rh) IL-15, the homeostatic factor for natural killer (NK) cells, is being clinically developed, but it has little antitumor activity alone. B7H3 (CD276) is an immune checkpoint inhibitor that is associated with poorer prognosis and is highly-expressed on prostate cancer. NK cells can be given as allogeneic products and, unlike T cells, do not induce cytokine-release syndrome or neurotoxicity. Here we developed a B7H3 targeting Tri-Specific Killer Engager (TriKE) as a novel dual camelid (cam) TriKE containing WT IL-15 and two cam engagers targeting CD16 on NK cells and B7H3 on tumor targets, making NK cells antigen specific. We have previously demonstrated that NK cells infiltrate prostate cancer tumors. As proof of concept, a clinical trial of a CD33-targeted TriKE for AML (NCT03214666) induced endogenous NK cell expansion and activation in refractory AML patients. Methods: Prostate cancer cell lines or patient-derived xenografts (PDX) were incubated with healthy donor or prostate cancer patient NK cells with or without B7H3 TriKE. PDX were propagated in NSG mice and then homogenized for in vitro assays. NK cell function was measured by flow cytometry and IncuCyte live tumor imaging assays. Castration-sensitive and -resistant prostate cancer (CSPC and CRPC, respectively) patient or normal donor peripheral blood mononuclear cells (PBMC) were immunophenotyped using 42-marker NK specific or broad immune cytometry time-of-flight (CyToF) panels. Results: B7H3 TriKE resulted in a dose-dependent proliferation of NK cells, but not T cells. This was in marked contrast to rhIL-15, which stimulated both cell types. camB7H3 was broadly expressed on prostate, head and neck, ovarian and glioblastoma cancers as well as multiple myeloma. We observed a B7H3 TriKE dose-dependent increase in CD107a degranulation and inflammatory cytokines to all B7H3 positive targets that was highly specific, with no response seen with B7H3 negative hematologic targets and CRISPR KO controls. Compared to rhIL-15, B7H3 TriKE given at molar equivalent dosing induced B7H3+ target killing in in a dose-dependent manner above that seen with rhIL-15 induced natural cytotoxicity. Using CSPC and CRPC patient PBMC (n=11-15), we demonstrated that there is no significant loss in NK cell degranulation/interferon gamma production or target cytotoxicity compared to healthy age- and sex-matched donors when treated with B7H3 TriKE. CyToF analysis of CSPC and CRPC patient PBMC is ongoing. In vivo activity in xenogeneic models of human tumor is underway. Conclusions: B7H3 TriKE delivers an NK cell specific IL-15 signal to expand NK cells and is highly specific against B7H3+ prostate cancer cell lines and PDX. Clinical-grade B7H3 TriKE is undergoing validation and a Phase 1/2 clinical trial is planned to open in the 3rd Quarter of 2024 for CRPC patients progressing on one or more therapies the CRPC setting.

Senescence-associated secretory phenotypes in mesenchymal cells contribute to cytotoxic immune response in oral lichen planus

Oral lichen planus is a chronic inflammatory condition that adversely affects the oral mucosa; however, its etiology remains elusive. Consequently, therapeutic interventions for oral lichen planus are limited to symptomatic management. This study provides evidence of the accumulation of senescent mesenchymal cells, CD8 + T cells, and natural killer cells in patients with oral lichen planus. We profiled the patients’ tissues using the National Center for Biotechnology Information Gene Expression Omnibus database and found that senescence-related genes were upregulated in these tissues by gene set enrichment analysis. Immunohistochemical analysis showed increased senescent mesenchymal cells in the subepithelial layer of patients with oral lichen planus. Single-cell RNA-seq data retrieved from the Gene Expression Omnibus database of patients with oral lichen planus revealed that mesenchymal cells were marked by the upregulation of senescence-related genes. Cell-cell communication analysis using CellChat showed that senescent mesenchymal cells significantly influenced CD8 + T cells and natural killer cells via CXCL12-CXCR4 signaling, which is known to activate and recruit CD8 + T cells and NK cells. Finally, in vitro assays demonstrated that the secretion of senescence-associated factors from mesenchymal cells stimulated the activation of T cells and natural killer cells and promoted epithelial cell senescence and cytotoxicity. These findings suggest that the accumulation of mesenchymal cells with senescence-associated secretory phenotype may be a key driver of oral lichen planus pathogenesis.

Features of T cell immunity depending on the content of natural killer cells in patients with acute coronary syndrome following COVID-19

We examined 65 men with unstable angina and acute myocardial infarction (acute coronary syndrome - ACS) from 40 to 65 years old who had previously had COVID-19 and 20 people with ACS who had not undergone COVID-19. All persons also had hypertension, and they required stenting of the coronary arteries within the next 3 days after admission to the hospital. From the immunological parameters by flow cytometry on the Navios cytofluorimeter (BeckmanCoulter, USA), according to the standardized technology for assessing the lymphocytic link of immunity [1], the following were determined: ), CD45+ CD3+ CD8+ (cytotoxic T-lymphocytes), CD45+CD3-CD19+ (B-lymphocytes), CD45+CD3+CD16+CD56+ (TNK cells), CD45+CD3-CD16+CD56+ (natural killer cells), CD45+ CD3+CD4+CD25+CD127- (T-regulatory cells), CD45+ CD3+CD4+CD25+ (T-lymphocytes - early activation), CD45+CD3+HLA-DR (T-lymphocytes - late activation). All patients were divided into groups depending on the content of NK cells (natural killer cells). Patients who have had COVID-19 have 3 phenotypes of disorders (decreased NK cell count, normal and increased), while non-survivors have 2 phenotypes (decreased NK cell count and normal). The most severe condition and severity of immune disorders were found in patients who had undergone COVID-19. In patients with acute coronary syndrome and COVID-19, predominantly with normal and elevated levels of NK cells, compared with ACS patients without COVID-19, a more severe course of the disease was observed - patients with acute myocardial infarction prevailed, they had a higher mortality rate, the duration of treatment was increased, and stent thrombosis was also more common. In persons with ACS and COVID-19 with elevated NK cells, the maximum decrease in the T-cell immunity was observed: T-lymphocytes of general, T-lymphocytes-helpers, T-cytotoxic lymphocytes, T-lymphocytes of early activation, T-regulatory cells in absolute numbers compared to other groups. The lowest immunoregulatory index and, at the same time, the maximum number of T-NK-lymphocytes were observed in persons who had undergone COVID-19 and had reduced NK cells. The minimum number of T-NK lymphocytes was recorded in patients with low NK cells who did not have COVID-19. Minimal T-lymphocytes (CD45+CD3+CD4+HLA-DR+) of late activation were found in people who recovered from COVID-19 with elevated and normal NK cells. The lowest number of late activation regulatory T cells was observed in patients who did not have COVID-19, but were vaccinated, and had a normal content of NK cells. The study also allows us to more clearly define the groups of patients with ACS who need additional immunocorrection.

Maintenance regimen of GM-CSF with rituximab and lenalidomide improves survival in high-risk B-cell lymphoma by modulating natural killer cells.

The treatment of high-risk B-cell lymphoma (BCL) remains a challenge, especially in the elderly. A total of 83 patients (median age 65 years), who have achieved a complete response after induction therapy, were divided into two groups: R2 + GM-CSF regimen (lenalidomide, rituximab, granulocyte-macrophage colony-stimulating factor [GM-CSF]) as maintenance therapy (n = 39) and observation (n = 44). The efficacy of the R2 + GM-CSF regimen as maintenance in patient with high-risk BCL was analyzed and compared with observation. The number of natural killer cells in patients increased after R2 + GM-CSF regimen administration (0.131 × 109 /L vs. 0.061 × 109 /L, p = 0.0244). Patients receiving the R2 + GM-CSF regimen as maintenance therapy had longer remission (duration of response: 18.9 vs. 11.3 months, p = 0.001), and longer progression-free survival (not reached (NR) vs. 31.7 months, p = 0.037), and overall survival (OS) (NR vs. NR, p = 0.015). The R2 + GM-CSF regimen was safe and well tolerated. High international prognostic index score (p = 0.012), and high tumor burden (p = 0.005) appeared to be independent prognostic factors for worse PFS. The maintenance therapy of R2 + GM-CSF regimen may improve survival in high-risk BCL patients, which might be modulated by amplification of natural killer cells. The efficacy of the R2 + GM-CSF maintenance regimen has to be further validated in prospective random clinical trials.

Effect of secretory DKK3 on circulating CD56bright natural killer cells in patients with liver cancer.

Liver cancer seriously threatens human health. Natural killer (NK) cells are an important part of the innate immune system and have strong anti-tumor ability. Immunotherapy based on NK cells has become a hot topic in the treatment of liver cancer. In this study, we checked the serum DKK3 (sDKK3) and circulating CD56bright NK cells using ELISA and flow cytometry, respectively, in the blood of liver cancer patients. The effect on recombinant human DKK3 (rhDKK3) on CD56bright NK cells was analyzed in vitro. We found low levels of sDKK3 in liver cancer patients and a negative correlation between sDKK3 and circulating CD56bright NK cells. In addition, we found that DKK3 induced the differentiation and improved the cytotoxicity of CD56bright NK cells for the first time. It could be used as an agonist for NK cell-based immunotherapy. Improving the clinical efficacy of NK cells through DKK3 will become a new strategy for cancer immunotherapy.

When Less Is More – Pipelle Endometrial Sampling for Quantification of Uterine Natural Killer Cells in Patients With Recurrent Implantation Failure or Habitual Abortion

Despite recent advancements in reproductive medicine, recurrent implantation failure and habitual abortion remain ongoing issues. One of the most important aspects of successful implantation is the intricate immune response and regulation necessary for the acceptance of the hemiallogenic embryo. The most numerous immune cells in the decidua are uterine natural killer cells (uNK). Studies suggest that changes in the uNK count and physiology may be responsible for the aforementioned pathological conditions. Thus, testing for uNK may provide valuable insights into their pathogenesis. The study compared Pipelle endometrial sampling with conventional curettage to find out whether the less invasive Pipelle method is a viable alternative of tissue collection. Tissue samples from 14 patients obtained by both methods were examined. The average size of tissue samples obtained with Pipelle was 17 mm2, samples obtained with curettage had on average 34 mm2. Using immunohistochemical visualization of CD56 (NK cells) and granzyme B antigens (serine protease-expressing activation state of NK cells), it was found that the average total count of CD56 / mm2 was for Pipelle 115 and 120 for curettage, respectively. The study also proved a correlation between granzyme B positivity and identification of NK cells clusters. The results indicated that Pipelle endometrial sampling seems a suitable method of tissue harvesting for the purpose of uNK cells examination. Pipelle endometrial sampling is safe, cost-effective and can be performed on an outpatient basis without the need of anesthesia or analgesia. Several issues remain yet to be solved: how to standardize the subsequent uNK testing, how to interpret the results and finally yet importantly, how to use this knowledge in personalized treatment protocols.

Literature Highlights.

Literature Highlights is a digest of notable papers recently published in the leading respiratory journals, allowing our readers to stay up-to-date with research advances. Coverage includes the latest Global Asthma Report; clinical trials of a new BCG vaccine; biomarkers for TB infection vs. active TB; different linezolid doses and durations in a shorter regimen for drug-resistant TB; use of multiplex PCR to reduce inappropriate antibiotic therapy; social contact patterns for airborne pathogens; and natural killer cells in patients with different states of TB infection.

Interaction between human leukocyte antigen (HLA-C) and killer cell Ig-like receptors (KIR2DL) inhibits the cytotoxicity of natural killer cells in patients with hepatoblastoma.

Hepatoblastoma (HB) is the most common liver malignancy in childhood with poor prognosis and lack of effective therapeutic targets. Single-cell transcriptome sequencing technology has been widely used in the study of malignant tumors, which can understand the tumor microenvironment and tumor heterogeneity. Two children with HB and a healthy child were selected as the research subjects. Peripheral blood and tumor tissue were collected for single-cell transcriptome sequencing, and the sequencing data were compared and analyzed to describe the differences in the immune microenvironment between children with HB and normal children. There were significant differences in the number and gene expression levels of natural killer cells (NK cells) between children with HB and normal children. More natural killer cells were seen in children with HB compared to normal control. KIR2DL were highly expressed in children with HB. Single-cell transcriptome sequencing of peripheral blood mononuclear cells (PBMC) and tumor tissue from children with HB revealed that KIR2DL was significantly up-regulated in NK cells from children with HB. HLA-C molecules on the surface of tumor cells interact with inhibitory receptor KIR2DL on the surface of NK cells, inhibiting the cytotoxicity of NK cells, resulting in immune escape of tumors. Inhibitors of related immune checkpoints to block the interaction between HLA-C and KIR2DL and enhance the cytotoxicity of NK cells, which may be a new strategy for HB treatment.

Percent Patient NK and T Cells at Day 28 Predict Graft Outcome after Haploidentical Hematopoietic Cell Transplant for Sickle Cell Disease

The only definitive cure for sickle cell disease (SCD) is hematopoietic cell transplant (HCT). Donor options are often limited due to the requirement of having a human leukocyte antigen (HLA)-matched donor. A haploidentical HCT from a family member has the potential to increase the donor pool for HCTs in SCD patients; however, conditioning regimens remain toxic. Reduced-intensity conditioning has the potential to successfully deplete the host immune system, reducing the rate of graft failure while also avoiding toxic side effects of traditional regimens. Natural killer (NK) cells are among the first cell lineages to repopulate following HCT, so sufficient depletion is necessary to ensure that the patient's NK cells will not target the donor cells post HCT. The primary objective of this study was to determine if a high percentage of patient NK cells at day 28 post-transplant could predict successful engraftment versus graft failure in SCD patients that have received a haploidentical HCT. Whole blood was drawn from SCD patients and their donors from two clinical trials (ClinicalTrials.gov Identifier: NCT02165007, NCT03077542) at baseline (before HCT) and at days 28, 60, 100, 180, and 365 following HCT. Peripheral blood mononuclear cells (PBMCs) were isolated via gradient-dependent lymphocyte separation and frozen for future batch analysis. Once samples from all time points were received, PBMCs were thawed and stained with fluorescent antibodies against CD3, CD4, CD8, CD45, CD56, iNKT, NKG2D, and HLA and analyzed by flow cytometry. HLA antibody optimization was achieved by screening for HLA mismatches between a patient and their haploidentical donor. Mann-Wilcoxon-Whitney rank tests were used to identify significant differences in various cell populations (CD3-CD56+ NK cells, CD3+ T cells) between patients with successful engraftment and those with graft failure. Areas under the receiver operating characteristic curve (AUCs) of the cell populations were used to determine which immune cell lineage held the highest potential to predict HCT graft failure at day 28. Statistical significance was established at p<0.05. A total of 15 patients were analyzed in this study: 11 patients had successful engraftment and 4 had graft failure. There were no statistically significant differences in the pre-HCT % NK or % T cell values in those who engrafted versus those who failed to engraft. At day 28 post-HCT, significant differences were noted between the % NK cells of all lymphocytes (p=0.0151) and % T cells of all lymphocytes (p=0.0028), as well as %-patient NK cells (p=0.0029) and %-patient T cells (p=0.0055) between the engrafted population and the graft failure population [Figure 1, A,B]. NK cells of all lymphocytes had an AUC of 0.9038 (95% Confidence Interval, CI, 0.573-1.00). T cells of all lymphocytes had an AUC of 0.9385 (95% CI 0.827-1.00). The AUC for %-patient T cells was 0.9273 (95% CI 0.779-1.00). Lastly, the AUC for %-patient NK cells was 0.9773 (95% CI 0.909-1.00). This suggested that the %-patient NK cells ROC model had the highest potential to correctly classify engraftment vs graft failure. This study showed the potential for using %-patient NK cells to predict graft failure at day 28 in SCD patients after haploidentical HCT, however, the sample size was limited. To independently validate these findings, analyses of specimens from a multisite clinical trial are being performed. Figure 1View largeDownload PPTFigure 1View largeDownload PPT Close modal

Circulating natural killer cells in patients with symptomatic atherosclerosis acquire the CD9+CD49A pro-inflammatory phenotype and support M1-like macrophage polarization

Background and Aims : Inflammation represents a hallmark of atherosclerosis (ATS), with monocytes/macrophages and T cells as the most investigated immune cells. Natural killer (NK) cells have been proposed as immunoregulatory cells in ATS, but the mechanisms still require investigations. We phenotypically and functionally characterized peripheral blood NK cells in patients with symptomatic atherosclerosis (sATS) and investigated their functional interactions with endothelial cells and monocyte/macrophages.

Abstract CT147: Phase 1 study of recombinant interleukin 15 (rhIL-15) in combination with checkpoint inhibitors nivolumab and ipilimumab in subjects with refractory cancers

Abstract Introduction: Recombinant human interleukin 15 (rhIL-15) has been shown to stimulate the activation and expansion in the number of effector T lymphocytes and natural killer cells in patients. The addition of the immune checkpoint inhibitors (ICI) CTLA-4 and PD-1 has shown increased antitumor efficacy in preclinical models, and the triplet is hypothesized to enhance anti-tumor immune response by augmenting effector cell expansion, differentiation, cytotoxic activity, and immune checkpoint inhibition. Results of the lead-in safety arms of rhIL-15/ipilimumab (Ipi) or rhIL-15/nivolumab (N) doublets were previously reported (O’Sullivan et al. AACR. 2019) and we now report results for the dose escalation phase of the triplet combination (NCT03388632). Methods: This phase 1, open-label, 3+3 dose escalation trial enrolled adult patients (pts) with measurable metastatic or refractory solid tumors and ECOG performance status ≤2. Prior therapy with 2 of the 3 study agents was permitted. Pts were treated on three dose levels (DL 1-3) of rhIL-15 (0.5, 1, or 2 mcg/kg/day) administered subcutaneously on days (D)1-8 and D22-29 of a 6-week cycle for the first 4 cycles only. Nivolumab (240mg IV) was administered on D8, 22, 36 and ipilimumab (1mg/kg IV) on D8 of every cycle. Response was assessed by RECIST 1.1. Upon progression, pts could continue for response assessment utilizing iRECIST if clinically stable and without toxicity. Treatment-induced changes in circulating and tumor T cell activation, signaling, and the PD-L1 checkpoint will be assessed with validated pharmacodynamic biomarker assays. Results: A total of 17 pts were enrolled on the triplet dose escalation phase; 15 pts were evaluable for response and 6 pts had received prior treatment with a PD-1/PD-L1 inhibitor. Median time on treatment (MTT) was 12 weeks (range 3-101). A confirmed partial response (PR) was observed in a pt with intrahepatic cholangiocarcinoma (MSI-H) after 3 cycles (total time on treatment 101 weeks). Across all dose levels, 7 pts (46.7%) had stable disease (SD) that prolonged their time on treatment with MTT of 20.4 weeks; 7 pts (46.7%) experienced progressive disease (PD) with MTT of 6.4 weeks. To better profile toxicity, 5 pts were replaced due to incomplete dosing of C1. Dose limiting toxicities at DL 3 (rhIL-15 at 2 mcg/kg/day) were photosensitivity and rash. Main drug-related adverse events included grade 4 lymphopenia (n=1) and grade 3 colitis, hyperthyroidism, hyponatremia, myocarditis, neutropenia, and photosensitivity (n=1, each). No pts discontinued therapy due to toxicity events. No deaths occurred on study. Conclusions: The recommended phase 2 dose (RP2D) of rhIL-15 is 1 mcg/kg/day when administered in combination with N+Ipi. The triplet dose expansion phase with the RP2D is currently accruing and includes biomarker studies in blood and tumor biopsies to assess the tumor microenvironment. This study was funded in part by NCI Contract HHSN261200800001E. *In memorium: Dr. Thomas Waldmann7. Citation Format: Sarah J. Shin, Geraldine O'Sullivan Coyne, Howard Streicher, Naoko Takebe, Ashley Bruns, Elad Sharon, Richard Piekarz, Lamin Juwara, Larry Rubinstein, Ralph Parchment, Kristin Fino, King L. Fung, Katherine Ferry-Galow, Arjun Mittra, Abdul Rafeh Naqash, Kevin Conlon, James H. Doroshow, Alice P. Chen. Phase 1 study of recombinant interleukin 15 (rhIL-15) in combination with checkpoint inhibitors nivolumab and ipilimumab in subjects with refractory cancers [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr CT147.

The combination of CD16A/EGFR innate cell engager, AFM24, with SNK01 autologous natural killer cells in patients with advanced solid tumors.

TPS2675 Background: Natural killer (NK) cells are a critical component of the innate immune system involved in the eradication of transformed cells via antibody-dependent cellular cytotoxicity (ADCC). For treatment of solid tumors autologous NK cell transfer represents a promising treatment strategy, with ex vivo expansion and activation enhancing the specificity and anti-tumor activity of NK cells. The efficacy of this approach may be enhanced through the addition of tumor-targeting antibodies, augmenting NK cell-mediated ADCC. Innate Cell Engagers (ICE) are bispecific antibodies that target a tumor cell-surface antigen and bind to CD16A expressed on NK cells. AFM24 is a novel ICE that targets epidermal growth factor receptor (EGFR), which is often overexpressed in solid tumors. The Phase 1 study of AFM24 monotherapy showed patients had a manageable safety profile, and SNK01 monotherapy has also shown to be well-tolerated in patients with rapidly progressive solid tumors. This study seeks to investigate AFM24 in combination with SNK01 autologous NK cells in patients with advanced EGFR+ solid tumors. Methods: An ongoing Phase 1/2a open-label, non-randomized, multicenter, dose escalation (Phase 1) and dose expansion (Phase 2a) study was initiated in November 2021 (NCT05099549) to evaluate the safety, tolerability and efficacy of AFM24 in combination with SNK01 NK cells in EGFR+ solid tumors. The primary aim of the Phase 1 study is to determine the maximum tolerated dose and/or recommended Phase 2 dose (RP2D) of AFM24 in combination with SNK01 at a fixed dose NK cells using a standard 3+3 design. Eligible patients must have advanced or metastatic disease with positive immunohistochemical staining for EGFR in &gt;1% of tumor cells and be refractory to standard-of-care treatment. Treatment begins with a safety lead-in phase with a single dose of AFM24 7 days prior to combination therapy. AFM24 will be administered at an escalating dose as weekly intravenous (IV) infusions; the starting dose (160 mg) and dose escalations for each cohort are based on results from the ongoing AFM24 monotherapy trial (NCT04259450). SNK01 NK cells will be given at a fixed dose (4.0 x109 cells) as a weekly IV infusion concomitantly with AFM24. Patients will receive combination therapy until disease progression, intolerable toxicity, patient withdrawal or termination at the investigator’s discretion. Phase 2 will then establish the overall response rate (as per RECIST v1.1) of combination therapy in patients with treatment refractory, advanced or metastatic squamous cell carcinoma of the head and neck, non-small cell lung cancer, or colorectal cancer as the primary endpoint. Efficacy will also be assessed by assessing progression-free and overall survival. Secondary endpoints for both phases include treatment-emergent adverse events, serious adverse events, pharmacokinetics and immunogenicity. Clinical trial information: NCT05099549.

Outcomes of Empirical Treatment With Intravenous Immunoglobulin G Combined With Low-Dose Aspirin in Women With Unexplained Recurrent Pregnancy Loss.

BackgroundTo assess the clinical efficacy of intravenous immunoglobulin G (IVIG) administration combined with low-dose aspirin in women with unexplained recurrent pregnancy loss (RPL).MethodsWe retrospectively analyzed the medical records of patients who had been diagnosed with unexplained RPL and treated with IVIG and low-dose aspirin between January 2000 and March 2020 at Asan Medical Center. We analyzed pregnancy outcomes and their association with the percentage of natural killer (NK) cells.ResultsThe study analyzed a total of 93 patients and 113 natural and assisted reproductive technology pregnancy cycles. The live birth rate per cycle was 73.5% (83/113), and the term delivery rate was 86.7% (72/83). The live birth rate was high regardless of the type of RPL, method of pregnancy, timing of IVIG treatment, and presence or absence of autoantibodies. In addition, the live birth rate was significantly higher in patients who received IVIG more than once, compared with patients who received IVIG only once (77.8% vs. 42.9%, P = 0.006). There was no significant association between the NK cell counts and live birth rate (65.5% in the group with NK cell < 12%, and 69.7% in that with NK cell ≥ 12%, P = 0.725). Among all patients, 87.6% had no complications, and there were no congenital malformation among newborn babies.ConclusionIVIG combined with low-dose aspirin treatment showed favorable pregnancy outcomes regardless of the patient’s NK cell counts (%).

The impact of hepatitis B surface antigen on natural killer cells in patients with chronic hepatitis B virus infection.

During chronic hepatitis B virus (HBV) infection, suppressed functionality of natural killer (NK) cells might contribute to HBV persistence but the underlying mechanisms remain elusive. A peculiar feature of HBV is the secretion of large amount of hepatitis B surface antigen (HBsAg). However, the effect of HBsAg quantities on NK cells is unclear. The aim was to determine the effects of HBsAg quantities on NK cell functionality in patients with chronic hepatitis B (CHB). Eighty CHB patients were included and categorized into four groups based on their HBsAg levels. As a control, 30 healthy donors were enrolled. NK cell frequency, phenotype and function were assessed using flow cytometry and correlated with HBsAg levels and liver enzymes. Compared to the healthy controls, a reshaping of NK cell pool towards more CD56bright NK cells was observed during CHB infection. Importantly, NK cells in patients with low HBsAg levels (<100IU/mL) displayed an activated phenotype with increased expression of activation makers CD38, granzyme B and proliferation marker Ki-67 while presenting with defective functional responses (MIP-1β, CD107a) at the same time. Furthermore, NK cell activation was negatively correlated with patient HBsAg levels while NK function correlated with patient age. The differential regulation of NK cell phenotype and function suggests that activation of NK cells in patients with low serum HBsAg levels may contribute to HBV clearance.

Astımlı Hastalarda Doğal Öldürücü (NK) Hücre İntrasitoplazmik ve Plazma Sitokin Seviyeleri

Astımlı Hastalarda Doğal Öldürücü (NK) Hücre İntrasitoplazmik ve Plazma Sitokin Seviyeleri

Magnesium levels and outcome after allogeneic hematopoietic stem cell transplantation in acute myeloid leukemia

Low intake of magnesium has been associated with the occurrence of lymphomas and decreased magnesium levels suppress the cytotoxic function of T cells and natural killer cells in patients with “X-linked immunodeficiency with magnesium defect, Epstein-Barr virus infection, and neoplasia” (XMEN) syndrome. These cell types are also important mediators of immune-mediated effects after allogeneic hematopoietic stem cell transplantation. Here, we show that high posttransplant magnesium levels independently associate with a lower incidence of relapse, a higher risk of acute graft-versus-host disease, and a higher non-relapse mortality in 368 patients with acute myeloid leukemia from our center. Magnesium serum levels might impact on donor-cell-mediated immune responses in acute myeloid leukemia.

Distinct mRNA and long non-coding RNA expression profiles of decidual natural killer cells in patients with early missed abortion.

Early non-chromosome-related missed abortion (MA) is commonly associated with an altered immunological environment during pregnancy. Human decidual natural killer (dNK) cells, the most abundant lymphocyte population within the first-trimester maternal-fetal interface, are vital maternal regulators of immune tolerance mediating successful embryo implantation and placentation. Previous studies have shown that dNK cells may play a role in MA. However, the gene expression status and specific altered manifestations of dNK cells in patients with early MA remain largely unknown. Here, we show that MA dNK cells have distinct mRNA and lncRNA expression profiles through RNA sequencing, with a total of 276 mRNAs and 67 lncRNAs being differentially expressed compared with controls. Protein-protein interaction analysis of differentially expressed mRNAs was performed to identify hub genes and key modules. An lncRNA-mRNA regulatory network characterized by the small-world property was constructed to reveal the regulation of mRNA transcription by differential hub lncRNAs. Functional annotation of differentially expressed mRNAs and lncRNAs was performed to disclose their potential roles in MA pathogenesis. Our data highlight several enriched biological processes (immune response, inflammatory response, cell adhesion, and extracellular matrix [ECM] organization) and signaling pathways (cytokine-cytokine receptor interaction, ECM-receptor interaction, Toll-like receptor signaling pathway, and phosphatidylinositol signaling system) that may influence MA. This study is the first to demonstrate the involvement of altered mRNA and lncRNA expression profiles in the dNK cell pathogenesis of early MA, facilitating a better understanding of the underlying molecular mechanisms and the development of novel MA therapeutic strategies targeting key mRNAs and lncRNAs.

Gene expression analysis of activating and inhibitory receptors of natural killer cells in patients with acute myeloblastic leukemia

PurposeNatural killer (NK) cells are cytotoxic lymphocytes, which have long been known to play an essential role in immune surveillance of tumor cells. The results of several clinical studies imply evidence of impaired activity of NK cells in acute myeloblastic leukemia (AML). The aim of this study was to investigate the gene expression of activating and inhibitory receptors of NK cells in patients with newly diagnosed AML before and after induction therapy using 7 + 3 regimen in comparison to healthy donors. Materials and methodsSixteen AML patients aged 16–64 years as well as 16 matched healthy individuals were studied. Peripheral blood samples from patients were obtained in two steps, namely, in newly diagnosed patients and 28 days after receiving induction therapy. Real-time PCR was performed to evaluate the expression levels of activating receptors, including DNAM-1 and NKp46 as well as inhibitory receptors of KIR2DL1 and NKG2A. ResultsOur results demonstrated that the newly diagnosed patients showed over 50% decrease in NKp46 expression and a 6-fold increase in KIR2DL1 expression compared to healthy controls. The mRNA expression analysis in patients after induction therapy suggested a significant decrease in mRNA expressions of KIR2DL1 and NKG2A in comparison to newly diagnosed patients. ConclusionHerewith, we show a statistical difference in mRNA expression levels of activating (NKp46) and inhibitory receptors from NK cells in newly diagnosed AML patients when compared with healthy controls or patients who received induction therapy, supporting the findings of researchers who reported the impaired NK cells cytotoxicity in AML patients.