Evaluating a combination treatment of NK cells and reovirus against bladder cancer cells using an in vitro assay to simulate intravesical therapy.

Intravesical treatment using either reovirus or natural killer (NK) cells serves as an efficient strategy for the treatment of bladder cancer cells (BCCs); however, corresponding monotherapies have often shown modest cytotoxicity. The potential of a locoregional combination using high-dose reovirus and NK cell therapy in an intravesical approach has not yet been studied. In this study, we evaluated the effectiveness of reoviruses and expanded NK cells (eNK) as potential strategies for the treatment of bladder cancer. The anti-tumor effects of mono-treatment with reovirus type 3 Dearing strain (RC402 and RP116) and in combination with interleukin (IL)-18/-21-pretreated eNK cells were investigated on BCC lines (5637, HT-1376, and 253J-BV) using intravesical therapy to simulate in vitro model. RP116 and IL-18/-21-pretreated eNK cells exhibited effective cytotoxicity against grade 1 carcinoma (5637 cells) when used alone, but not against HT-1376 (grade 2 carcinoma) and 253J-BV cells (derived from a metastatic site). Notably, combining RP116 with IL-18/-21-pretreated eNK cells displayed effective cytotoxicity against both HT-1376 and 253J-BV cells. Our findings underscore the potential of a combination therapy using reoviruses and NK cells as a promising strategy for treating bladder cancer.

Platycodin D induces apoptosis via regulating MAPK pathway and promotes autophagy in colon cancer cell.

Platycodin D (PD) is the main component of triterpene saponins found in Platycodi radix. In this study, we observed a decrease in cell viability, an increase in apoptotic bodies, and an increase in the rate of apoptosis. Also, we observed an increase in cleaved PARP and Bax, a decrease in Bcl-2, and p-ERK, and an increase in p-p38 and p-JNK. Furthermore, a change in cell viability and the expression of p-p38, Bax, and Bcl-2 using the p38 inhibitor revealed a decrease in p-p38 and Bax and an increase in Bcl-2 in the inhibitor treatment group. In addition, we observed an increase in vacuole formation through morphological changes and an increase in acidic vesicular organelles (AVOs). We also observed an increase in the expression of beclin 1, LC 3-I, and -II. There was no significant decrease in cell viability in the group treated with 3-MA, but a decrease in cell viability was noted in the group treated with HCQ. HCQ treatment resulted in an increase in Bax and a decrease in Bcl-2. These findings reveal that in HT-29 colon cancer cells, PD induces apoptosis through the MAPK pathway, thereby exerting anticancer effects. Moreover, autophagy caused by PD inhibits apoptosis by protecting the cells.

Comparative analysis of the aberrant immunophenotype and clinical characteristics in dogs with lymphoma: a study of 27 cases.

Introduction: Aberrant lymphoma phenotypes are frequently found in dogs, but the clinical implications are sparse. Methods: Twenty-seven dogs with aberrant lymphoma diagnosed using flow cytometry between 2017 and 2023 were analyzed. Major paraneoplastic syndromes, prognostic factors, and clinical features of lymphoma were compared to their immunophenotypes. Results: Twenty-seven dogs had aberrant immunophenotypes, with MHCII- (48%) and CD3+/CD21+ (44%) being the most commonly identified aberrancies. In B-cell lymphoma, the most frequent aberrancies were MHC II- (53%), CD3+/CD21+ (41%), CD34+ (24%), and CD79a- (24%). Meanwhile, in T-cell lymphoma, CD3+/CD21+ (63%), CD4-/CD8-(50%), CD5- (50%), and CD45- (50%) were the most common. The platelet-neutrophil ratio was significantly higher in the CD3+/CD21+ group than in the other groups, where either one or both markers were not expressed (55.23 ± 39.64; 18.72 ± 14.95, respectively; p = 0.001). Serum albumin concentration was significantly lower in the MHCII-group (2.59 g/dL, 95% CI 2.31-2.87) than in the MHCII+ group (3.06 g/dL, 95% CI 2.88-3.23; p = 0.009). CD34 expression showed significant correlations with cranial mediastinal mass, WHO clinical substage, and fever (p = 0.028, p = 0.041, and p = 0.047, respectively). MHCII expression was correlated with adverse reactions to chemotherapy, cranial mediastinal masses, and fever (p = 0.009, p = 0.023, and p < 0.001, respectively). No statistically significant differences in the survival period were observed for any of the phenotypic aberrancies. Conclusion: Aberrant lymphomas are common in dogs. Some clinical prognostic factors that significantly correlate with aberrant immunophenotypes have been identified and can be applied clinically.

Intensified NK cell therapy in combination with low-dose chemoradiotherapy against human colorectal cancer.

The therapeutic potential of adoptive natural Killer (NK) cells immunotherapy in combination with chemoradiotherapy, the main treatment modality for colorectal cancer (CRC), has not yet been explored. Here, we aimed to investigate the efficacy of NK cells to potentiate primary tumor control and improve survival outcomes, especially in combination with low-dose chemoradiotherapy. Ex vivo activated NK cells (> 90% purity) from healthy donors were obtained. NK cells were administered intravenously to the CRC-bearing mice and intensified in vivo in combination with low-dose 5-fluorouracil (0.5 mg/kg or 1 mg/Kg) and irradiated tumors with low doses (2 Gy or 4 Gy). Real-time NK cell cytotoxicity demonstrated a synergistic killing effect of a combination of low-dose chemoradiotherapy, mainly through NKp30 and NKG2D, showing a decrease in NK cell degranulation after blocking NKG2D and NKp30. In vivo tumor characteristics after combination treatment showed decreased CD112, CD155, MICA, and MICB expression. Under the combination strategy, 70% of the mice had free lung metastasis and 90% without secondary gross tumors, indicating suppressed distant metastasis to lung and axillary regions. This combination therapy resulted in significantly synergistic antitumor activity against primary solid tumors compared to chemoradiotherapy only. Furthermore, the intensified NK cell administration showed significantly better primary tumor control and survival outcomes than the non-intensified NK cell administration in a human colorectal HT-29 model treated with low-dose chemoradiotherapy. Optimized NK cell therapy combined with low-dose chemoradiotherapy can provide effective therapeutic potential for intractable cold human colorectal cancer.

Viscum album Induces Apoptosis by Regulating STAT3 Signaling Pathway in Breast Cancer Cells.

In this study, we investigated the potential anticancer effects of Viscum album, a parasitic plant that grows on Malus domestica (VaM) on breast cancer cells, and explored the underlying mechanisms. VaM significantly inhibited cell viability and proliferation and induced apoptosis in a dose-dependent manner. VaM also regulated cell cycle progression and effectively inhibited activation of the STAT3 signaling pathway through SHP-1. Combining VaM with low-dose doxorubicin produced a synergistic effect, highlighting its potential as a promising therapeutic. In vivo, VaM administration inhibited tumor growth and modulated key molecular markers associated with breast cancer progression. Overall, our findings provide strong evidence for the therapeutic potential of VaM in breast cancer treatment and support further studies exploring clinical applications.

Chrysin Induces Apoptosis via the MAPK Pathway and Regulates ERK/mTOR-Mediated Autophagy in MC-3 Cells.

Chrysin is a flavonoid found abundantly in substances, such as honey and phytochemicals, and is known to exhibit anticancer effects against various cancer cells. Nevertheless, the anticancer effect of chrysin against oral cancer has not yet been verified. Furthermore, the mechanism underlying autophagy is yet to be clearly elucidated. Thus, this study investigated chrysin-mediated apoptosis and autophagy in human mucoepidermoid carcinoma (MC-3) cells. The change in MC-3 cell viability was examined using a 3-(4,5-dimethylthiazolyl-2)-2, 5-diphenyltetrazolium bromide cell viability assay, as well as 40,6-diamidino-2-phenylindole, annexin V, and propidium iodide staining. Western blotting was used to analyze the proteins related to apoptosis and the mitogen-activated protein kinase (MAPK) pathway. In addition, the presence or absence of autophagy and changes in the expression of related proteins were investigated using acridine orange staining and Western blot. The results suggested that chrysin induced apoptosis and autophagy in MC-3 oral cancer cells via the MAPK/extracellular signal-regulated kinase pathway. Moreover, the induced autophagy exerted a cytoprotective effect against apoptosis. Thus, the further reduced cell viability due to autophagy as well as apoptosis induction highlight therapeutic potential of chrysin for oral cancer.

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. Here, we present an effective expansion method using genetically modified K562-HLA-E feeder cells for long-term proliferation of adaptive NK cells displaying highly differentiated phenotype and comparable cytotoxicity, CD107a, and interferon-γ (IFN-γ) production. More importantly, our expansion method achieved more than a 10,000-fold expansion of adaptive NK cells after 6 weeks of culture, providing a high yield of alloreactive NK cells for cell therapy against cancer.

Myricetin induces apoptosis through the MAPK pathway and regulates JNK­mediated autophagy in SK­BR­3 cells.

Myricetin, a flavonoid found in fruits and vegetables, is known to have antioxidant and anticancer effects. However, the anticancer effects of myricetin on SK­BR­3 human breast cancer cells have not been elucidated. In the present study, the anticancer effects of myricetin were confirmed in human breast cancer SK­BR­3 cells. As the concentration of myricetin increased, the cell viability decreased. DAPI (4',6­diamidino­2­phenylindole) and Annexin V/PI staining also revealed a significant increase in apoptotic bodies and apoptosis. Western blot analysis was performed to confirm the myricetin­induced expression of apoptosis­related proteins. The levels of cleaved PARP and Bax proteins were increased, and that of Bcl­2 was decreased. The levels of proteins in the mitogen­activated protein kinase (MAPK) pathway were examined to confirm the mechanism of myricetin­induced apoptosis, and it was found that the expression levels of phosphorylated c­Jun N­terminal kinase (p­JNK) and phosphorylated mitogen­activated protein kinases (p­p38) were increased, whereas that of phosphorylated extracellular­regulated kinase (p­ERK) was decreased. It was also demonstrated that myricetin induced autophagy by promoting autophagy­related proteins such as microtubule­associated protein 1A/1B­light chain 3 (LC 3) and beclin 1. In addition, 3­methyladenine (3­MA) was used to evaluate the association between cell viability and autophagy in cells treated with myricetin. The results showed that simultaneous treatment with 3­MA and myricetin promoted the apoptosis of breast cancer cells. Furthermore, treatment with a JNK inhibitor reduced cell viability, promoted Bax expression, and reduced the expression of p­JNK, Bcl­2, and LC 3­II/I. These results suggest that myricetin induces apoptosis via the MAPK pathway and regulates JNK­mediated autophagy in SK­BR­3 cells. In conclusion, myricetin shows potential as a natural anticancer agent in SK­BR­3 cells.

A case of leukaemia cutis in a dog with T-cell chronic lymphocytic leukaemia.

Leukaemia cutis (LC) is the infiltration of neoplastic leukocytes into the skin, characterised by haemorrhagic papules, nodules, and plaques. LC has been reported in human leukaemia patients, but it is extremely rare in dogs. A 13-year-old spayed female Golden Retriever that was previously diagnosed with chronic lymphocytic leukaemia was managed with chlorambucil (20 mg/m2 orally, every 2 weeks) and prednisolone (2 mg/kg orally, every other day) for 8 months; however, immunosuppression was temporarily discontinued because of a bacterial urinary tract infection. Cutaneous signs, including multifocal ecchymosis and white plaques, appeared 1 month after cessation of chemotherapy. Histopathological examination revealed small- to intermediate-sized lymphocytes with mild atypia in a perivascular to interstitial pattern within the superficial dermis. The bands of atypical cells within the superficial dermis were strongly and extensively positive for CD3 on immunohistochemistry. Polymerase chain reaction analysis of the biopsied skin revealed clonal rearrangement of the T-cell receptor gamma locus gene. Given the evidence of clinical signs, peripheral immunophenotyping, histopathology, immunohistochemistry, and clonal gene arrangement, LC was diagnosed. The lesions disappeared when chemotherapy was restarted but were occasionally observed when chemotherapy was stopped. To the authors' best knowledge, this is the first case report of LC in a dog.

Safety analysis of ex vivo-expanded canine natural killer cells in a xenogeneic mouse model of graft-versus-host disease.

Canine natural killer (NK) cells are large, granular lymphocytes that are neither B lymphocytes nor T lymphocytes. However, it has been reported that canine NK cells share some of the phenotypic characteristics of T lymphocytes, such as CD3 and CD5. Studies are needed to assess the safety of canine NK cells for immunotherapy, especially because the safety of using allogeneic NK cells as an immunotherapy for dogs has yet to be shown. In this study, the safety of cultured canine NK cells was assessed using a xenogeneic mouse model of graft-versus-host disease (GVHD). Mice were injected with either canine peripheral blood mononuclear cells (PBMCs) or cultured NK cells for 2 or 3 weeks. Data were then collected on changes in mice body weights, disease severity scores, and survival rates. Histopathological and immunohistochemical evaluations were also performed. All mice injected with canine PBMCs died within 45 days after injection. Severe clinical signs were caused by GVHD. The histopathological and immunohistochemical evaluations showed that mice injected with canine PBMCs had multiple lesions, including necrosis in their lungs, livers, kidneys, and stomachs, and the injected cells were present around the lesions. By contrast, no mice injected with cultured NK cells without removing the CD3+ TCR- cells exhibited any clinical abnormalities. Moreover, they all survived the 90-day experimental period without exhibiting any histopathological changes. Accordingly, the results of this study suggest that canine NK cells do not cause significant side effects such as GVHD and allogeneic NK cells can safely be used for cancer immunotherapy in dogs.

Comparison of clinical and inflammatory parameters in dogs with pyometra before and after ovariohysterectomy.

This study aimed to identify potential biomarkers of canine pyometra and their correlations with clinical parameters. First, 90 dogs with pyometra and 26 healthy female dogs were compared. Then, paired samples (before and after ovariohysterectomy) from 22 dogs with pyometra and 9 healthy controls from the initial cohort were compared. Concentrations of acute inflammatory proteins, C-reactive protein (CRP) and serum amyloid A (SAA), and cell-free DNA (cfDNA), were significantly higher in dogs with pyometra than in clinically healthy dogs. Cell-free DNA was the most sensitive biomarker for systemic inflammation, based on the receiver operating characteristic curve analysis (area under the curve = 0.959). In addition, cfDNA and CRP were significantly associated with inflammation and organ injury-related clinical parameters. Following the surgical removal of the inflamed uterus, interleukin-6 (IL-6), high-mobility group box 1 (HMGB1), and procalcitonin (PCT) significantly decreased, whereas changes in CRP, SAA, and cfDNA were not significant. These findings indicate that cfDNA, CRP, and SAA are potential clinical biomarkers of systemic inflammation in dogs with pyometra and PCT, IL-6, and HMGB1 are potential biomarkers of clinical recovery.

Cette étude visait à identifier les biomarqueurs potentiels du pyomètre canin et leurs corrélations avec les paramètres cliniques. Tout d'abord, 90 chiens avec pyomètre et 26 chiennes en bonne santé ont été comparés. Ensuite, des échantillons appariés (avant et après ovariohystérectomie) de 22 chiens avec pyomètre et neuf témoins sains de la cohorte initiale, ont été comparés.Les concentrations des protéines inflammatoires aiguës, protéine C réactive (CRP) et amyloïde sérique A (SAA), et d'ADN acellulaire (cfDNA), étaient significativement plus élevées chez les chiens atteints de pyomètre que chez les chiens cliniquement sains. L'ADN acellulaire était le biomarqueur le plus sensible pour l'inflammation systémique, sur la base de l'analyse de la courbe caractéristique de fonctionnement du récepteur (aire sous la courbe = 0,959). De plus, le cfDNA et la CRP étaient significativement associés à l'inflammation et aux paramètres cliniques liés aux lésions aux organes.Après l'ablation chirurgicale de l'utérus enflammé, l'interleukine-6 (IL-6), la protéine HMGB1 (« high-mobility groupe box 1 ¼) et la procalcitonine (PCT) ont significativement diminué, alors que les changements de CRP, SAA et cfDNA n'étaient pas significatifs. Ces résultats indiquent que cfDNA, CRP et SAA sont des biomarqueurs cliniques potentiels de l'inflammation systémique chez les chiens avec pyomètre et PCT, IL-6 et HMGB1 sont des biomarqueurs potentiels de récupération clinique.(Traduit par Docteur Serge Messier).

Live cell imaging of highly activated natural killer cells against human hepatocellular carcinoma in vivo.

BACKGROUND AIMS: Tracking administered natural killer (NK) cells in vivo is critical for developing an effective NK cell-based immunotherapy against human hepatocellular carcinoma (HCC). Here the authors established a new molecular imaging using ex vivo-activated NK cells and investigated real-time biodistribution of administered NK cells during HCC progression. METHODS: Ex vivo-expanded NK cells from healthy donors were labeled with a near-infrared lipophilic cytoplasmic dye, and their proliferation, surface receptor expression and cytotoxicity activity were evaluated. Human HCC HepG2 cells were implanted into the livers of NOD.Cg-Prkdcscid IL2rgtm1Wjl/SzJ (NSG) mice. The authors administered 1,1'-dioctadecyltetramethyl indotricarbocyanine iodide (DiR)-labeled NK cells intravenously to non-tumor-bearing and intrahepatic HCC tumor-bearing NSG mice. Fluorescent imaging was performed using a fluorescence-labeled organism bioimaging instrument. Single cell suspensions from the resected organs were analyzed using flow cytometry. RESULTS: The fluorescent DiR dye was nontoxic and did not affect the proliferation or surface receptor expression levels of the NK cells, even at high doses. The administered DiR-labeled NK cells immediately migrated to the lungs of the non-tumor-bearing NSG mice, with increased NK cell signals evident in the liver and spleen after 4 h. NK cells migrated to the intrahepatic tumor-bearing livers of both early- and late-stage HCC mice within 1 h of injection. In early-stage intrahepatic tumor-bearing mice, the fluorescence signal increased in the liver until 48 h post-injection and decreased 7 days after NK injection. In late-stage HCC, the NK cell fluorescence signal was the highest in the liver for 7 days after NK injection and persisted for 14 days. The purity of long-term persistent CD45+CD56+CD3- NK cells was highest in early- and late-stage HepG2-bearing liver compared with normal liver 2 weeks after NK injection, whereas highest purity was still observed in the lungs of non-tumor-bearing mice. In addition, Ki-67 expression was detected in migrated human NK cells in the liver and lung up to 72 h after administration. With HepG2 tumor progression, NK cells reduced the expression of NKp30 and NKG2D. CONCLUSIONS: Administered NK cells were successfully tracked in vivo by labeling the NK cells with near-infrared DiR dye. Highly expanded, activated NK cells migrated rapidly to the tumor-bearing liver, where they persisted for 14 days after administration, with high purity of CD45+CD56+CD3- NK cells. Liver biodistribution and persistence of administered NK cells showed significantly different accumulation patterns during HCC progression.

Safety and immunological effects of recombinant canine IL-15 in dogs.

Interleukin-15 (IL-15) is a pleiotropic cytokine that plays pivotal roles in innate and adaptive immunity. It is also a promising cytokine for treating cancer. Despite growing interest in its use as an immunotherapeutic, its safety and immunological effects in dogs have not been reported. In this study, healthy dogs were given recombinant canine IL-15 (rcIL-15) intravenously at a daily dose of 20 µg/kg for 8 days and monitored for 32 days to determine the safety and immunological effects of rcIL-15. The repeated administration of rcIL-15 was well tolerated, did not cause any serious side effects, and promoted the selective proliferation and activation of canine anti-cancer effector cells, including CD3+CD8+ cytotoxic T lymphocytes, CD3+CD5dimCD21-, and non-B/non-T NK cell populations, without stimulating Treg lymphocytes. The rcIL-15 injections also stimulated the expression of molecules and transcription factors associated with the activation and effector functions of NK cells, including CD16, NKG2D, NKp30, NKp44, NKp46, perforin, granzyme B, Ly49, T-bet, and Eomes. These results suggest that rcIL-15 might be a valuable therapeutic adjuvant to improve immunity against cancer in dogs.

Apigenin induces apoptosis by regulating Akt and MAPK pathways in human melanoma cell A375SM.

Apigenin, an aromatic compound, exhibits antioxidant, anti­inflammatory and anti­viral effects. The present study aimed to investigate the effects of apigenin on cell proliferation and apoptosis of human melanoma cells A375P and A375SM. Therefore, melanoma cells were treated with apigenin to determine its anti­proliferative and survival effects, using wound healing and MTT assays. The results revealed that melanoma cell viability was decreased in a dose­dependent manner. Furthermore, chromatin condensation, indicating apoptosis, was significantly increased in a dose­dependent manner, as demonstrated by DAPI staining. In addition, increased apoptosis rate following treatment with apigenin was confirmed by Annexin V­propidium iodide staining. The changes in the expression levels of apoptosis­related proteins in A375P and A375SM melanoma cells were subsequently detected using western blot analysis. The results demonstrated that the protein expression levels of Bcl­2 were decreased, whereas those of Bax, cleaved poly ADP­ribose polymerase, cleaved caspase­9 and p53 were upregulated in a dose­dependent manner in apigenin­treated cells compared with those noted in untreated cells. In addition, in apigenin­treated A375P cells, phosphorylated (p)­p38 was upregulated and p­extracellular signal­regulated kinase (ERK), p­c­Jun N­terminal kinase (JNK) and p­protein kinase B (Akt) were downregulated. However, in A375SM cells, apigenin treatment increased p­ERK and p­JNK and decreased p­p38 and p­Akt protein expression levels. Subsequently, the inhibitory effect of apigenin on tumor growth was investigated in vivo. Tumor volume was significantly reduced in the 25 and 50 mg/kg apigenin­treated groups compared with the control group. Additionally, a TUNEL assay was performed to detect apoptotic cells. Immunohistochemical staining also revealed elevated p­ERK expression in the apigenin­treated group compared with the control group. Overall, the findings of the present study indicated that apigenin attenuated the growth of A375SM melanoma cells by inducing apoptosis via regulating the Akt and mitogen­activated protein kinase signaling pathways.

Combined NK Cell Therapy and Radiation Therapy Exhibit Long-Term Therapeutic and Antimetastatic Effects in a Human Triple Negative Breast Cancer Model.

PURPOSE: We investigated whether adoptive cell therapy with ex vivo-activated natural killer (NK) cells enhances the therapeutic efficacy of local tumor radiation therapy (RT) using a human triple-negative breast cancer xenograft model. METHODS AND MATERIALS: NK cells from healthy donors were expanded ex vivo. MDA-MB-231/Luc-GFP cells were subcutaneously implanted into the thighs of NSG mice. The animals were divided into 4 experimental groups: control, RT, NK, and RT + NK. On day 17 after tumor implantation, tumors from the RT groups were irradiated. The ex vivo-expanded NK cells were intravenously administered twice, on days 17 and 19. Primary and secondary tumors were evaluated using long-term bioluminescence imaging, and histopathology was performed on resected tumor tissue specimens. RESULTS: The luciferase signals of the primary tumors in the RT + NK group were significantly lower than those of comparably sized primary tumors in the RT group. The long-term migration and infiltration of NK cells into the primary tumor sites were significantly higher in RT + NK than in NK mice. Moreover, lymphatic metastasis to the axillary lymph nodes and liver and lung metastases were highly suppressed in the RT + NK group, as demonstrated by BLI and p53 immunohistochemistry. The long-term survival of the RT + NK group was significantly higher than that of the RT or NK groups. CONCLUSIONS: Reduction in tumor burden by combining RT and systemic NK cell therapy improved the suppression of primary tumor growth, with efficient NK cell migration and penetration into the primary tumor site. Administered NK cells were maintained in the primary tissue for a significantly longer time in RT + NK group compared with NK group. Both lymphatic spread and distant metastasis to the lungs and liver were effectively suppressed by the combined therapy.

Canine non-B, non-T NK lymphocytes have a potential antibody-dependent cellular cytotoxicity function against antibody-coated tumor cells.

BACKGROUND: The antibody-dependent cellular cytotoxicity (ADCC) is a cell-mediated immune defense mechanism in which effector immune cells actively lyse antibody-coated target cells. The ADCC of tumor cells is employed in the treatment of various cancers overexpressing unique antigens, and only natural killer (NK) cells are known to be major effectors of antibody mediated ADCC activity. Canine NK cells are still defined as non-B, non-T large granular lymphocytes because of the lack of information regarding the NK cell-restricted specific marker in dogs, and it has never been demonstrated that canine NK cells have ADCC ability against tumor cells. In the present study, we investigated whether canine non-B, non-T NK cells have ADCC ability against target antibody-coated tumor cells, using cetuximab and trastuzumab, the only human antibodies reported binding to canine cancer cells. RESULTS: Activated canine non-B, non-T NK cells (CD3-CD21-CD5-TCRαß-TCRγδ-) for 13~17 days ex vivo showed ADCC ability against trastuzumab- or cetuximab-coated target tumor cells expressing various levels of human epidermal growth factor receptor 2 (HER-2) and epidermal growth factor receptor (EGFR). Trastuzumab and cetuximab induced significant ADCC responses of canine NK cells even in CMT-U334 and CF41.Mg cells expressing low levels of HER-2 and/or EGFR, as well as in SKBR3 and DU145 cells overexpressing HER-2 and/or EGFR. The trastuzumab-mediated ADCC activity of NK cells was significantly enhanced by treatment with rcIL-21. CONCLUSIONS: The results of this study suggest that canine non-B, non-T NK lymphocytes have a potential ADCC function and that combinational strategies of monoclonal antibodies with either cytokines, which activate NK cells in vivo, or adoptive transfer of NK cells may be a feasible method for amplifying the efficacy of immunotherapy against malignant cancers even with very low expression of target molecules in dogs.

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

Background: 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 ex vivo 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. Methods: K562-OX40L cells were generated by lentiviral transduction and were used as feeder cells to expand and activate NK cells from PBMCs in the presence of IL-2/IL-15. Soluble IL-21 was also added in various concentrations only once at the beginning of the culture. NK cells were expanded for 4-5 weeks, and the purity, expansion rate, phenotype and function (cytotoxicity, antibody-dependent cell-mediated cytotoxicity (ADCC), cytokine production, CD107a degranulation) of these expanded NK cells were compared to those generated by using K562 feeder cells. Results: The culture of NK cells with K562-OX40L cells in combination with the transient exposure to IL-21 highly enhanced NK cell expansion to approximately 2,000-fold after 4 weeks of culture, compared to a 303-fold expansion using the conventional K562 cells. Mechanistically, the OX40-OX40L axis between the feeder cells and NK cells as well as the homotypic interaction between NK cells through the OX40-OX40L axis were both necessary for NK cell expansion. The short exposure of NK cells to IL-21 had a synergistic effect with OX40 signaling for NK cell expansion. Apart from their enhanced expansion, NK cells grown with K562-OX40L feeder cells were similar to those grown with conventional K562 cells in regard to the surface expression of various receptors, cytotoxicity, ADCC, cytokine secretion, and CD107 degranulation. Conclusion: Our data suggest that OX40 ligand is a potent co-stimulant for the robust expansion of human NK cells and the homotypic NK cell interactions through the OX40-OX40L axis is a mechanism of NK cell expansion.

Identification of microsatellite markers and their application in yellow catfish (Pseudobagrus fulvidraco Richardson, 1846) population genetics of Korea.

Microsatellite markers from a fresh water yellow catfish, Pseudobagrus fulvidraco, were developed by whole-genome sequencing in the Ion S5 system. Of the 40 chosen sets of microsatellite markers, with tetra-repeat and penta-repeat motifs, from a total 19,743 sequence, only 13 markers were successfully applied in 78 individual fish sampled to detect genomic variability from four natural populations of Korea. On an average, the number of alleles per marker was 6.7. The observed heterozygosity varied from 0.048 to 0.810. Twelve microsatellite markers conformed to Hardy-Weinberg equilibrium and none exhibited significant linkage disequilibrium. In yellow catfish, genetic differentiation among four natural populations was further supported by FST (P < 0.05) and STRUCTURE analysis. The microsatellite markers identified could facilitate genetic diversity and population structure studies and thus aid in conservation of the yellow catfish.

Cellular immunotherapy in multiple myeloma.

In multiple myeloma (MM), the impaired function of several types of immune cells favors the tumor's escape from immune surveillance and, therefore, its growth and survival. Tremendous improvements have been made in the treatment of MM over the past decade but cellular immunotherapy using dendritic cells, natural killer cells, and genetically engineered T-cells represent a new therapeutic era. The application of these treatments is growing rapidly, based on their capacity to eradicate MM. In this review, we summarize recent progress in cellular immunotherapy for MM and its future prospects.

Effects of irradiation and leukoreduction on down-regulation of CXCL-8 and storage lesion in stored canine whole blood.

White blood cells (WBCs) and storage period are the main factors of transfusion reactions. In the present study, cytokine/chemokine concentrations after leukoreduction (LR) and irradiation (IR) in stored canine whole blood were measured. Red blood cell storage lesion caused by IR and LR were also compared. Blood samples from 10 healthy Beagles were divided into four groups (no treatment, LR-, IR-, and LR + IR-treated). Leukocytes were removed by filtration in the LR group and gamma radiation (25 Gy) was applied in the IR group. Immunologic factors (WBCs, interleukin-6 [IL-6], C-X-C motif chemokine ligand 8 [CXCL-8], and tumor necrosis factor-alpha) and storage lesion factors (blood pH, potassium, and hemolysis) were evaluated on storage days 0, 7, 14, 21, and 28. Compared to the treated groups, IL-6 and CXCL-8 concentrations during storage were significantly higher in the control (no treatment) group. LR did not show changes in cytokine/chemokine concentrations, and storage lesion presence was relatively mild. IR significantly increased CXCL-8 after 14 days of storage, but IR of leukoreduced blood did not increase CXCL-8 during 28 days of storage. Storage lesions such as hemolysis, increased potassium, and low pH were observed 7 days after IR and storage of blood, regardless of LR. IR of leukoreduced blood is beneficial to avoid immune reactions; however, storage lesions should be considered upon storage.