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1.
Hematol., Transfus. Cell Ther. (Impr.) ; 45(4): 419-427, Oct.-Dec. 2023. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1528655

RESUMO

ABSTRACT Introduction and hypothesis: Umbilical cord blood (UCB) is an alternative source of hematopoietic stem cells for allogeneic hematopoietic stem cell transplantation in the absence of a compatible donor. The UCB transplantation has a lower incidence of chronic graft versus host disease (GvHD), but is associated with slower engraftment and slower immune reconstitution, compared to other sources. Dendritic cells (DCs) and Natural Killer cells (NKs) play a central role in the development of GvHD and the graft versus leukemia (GvL) effect, as well as in the control of infectious complications. Method: We quantified by multiparametric flow cytometry monocytes, lymphocytes, NK cells, and DCs, including their subsets, in UCB samples from 54 healthy newborns and peripheral blood (PB) from 25 healthy adult volunteers. Results: In the UCB samples, there were higher counts of NK cells 56bright16- (median 0.024 × 109/L), compared to the PB samples (0.012 × 109/L, p < 0.0001), NK 56dim16bright (median 0.446 × 109/L vs. 0.259 × 109/L for PB samples, p = 0.001) and plasmacytoid dendritic cells (pDCs, median 0.008 × 109/L for UCB samples vs. 0.006 × 109/L for PB samples, p = 0.03). Moreover, non-classic monocyte counts were lower in UCB than in PB (median 0.024 × 109/L vs. 0.051 × 109/L, respectively, p < 0.0001). Conclusion: In conclusion, there were higher counts of NK cells and pDCs and lower counts of non-classic monocytes in UCB than in PB from healthy individuals. These findings might explain the lower incidence and severity of chronic GvHD, although maintaining the GvL effect, in UCB transplant recipients, compared to other stem cell sources.


Assuntos
Sangue Fetal
2.
Artigo em Chinês | WPRIM | ID: wpr-1003808

RESUMO

Adoptive cell immunotherapy has been a hot spot in tumor research in recent years. Chimeric antigen receptor T cells (CAR-T) have achieved great success in hematological tumors and have changed the current tumor treatment landscape to a certain extent. However, the application of CAR-T therapy in clinics is limited due to its serious side effects and high treatment costs. Natural killer (NK) cells are important immune cells in the body and have native cytotoxicity and well safety. NK cells based on CAR engineering (CAR-NK) have shown powerful anti-tumor activity and safety in preclinical research and could be the next generation of CAR platform-based cellular immunotherapy. This review will systematically introduce the current research status of CAR-NK cells in lymphoma.

3.
Zhongguo yi xue ke xue yuan xue bao ; Zhongguo yi xue ke xue yuan xue bao;(6): 290-297, 2023.
Artigo em Chinês | WPRIM | ID: wpr-981266

RESUMO

Although the development of novel drugs has significantly improved the survival of patients with multiple myeloma (MM) over the past decades,the lack of effective therapeutic options for relapsed and refractory MM results in poor prognosis.The chimeric antigen receptor (CAR) T-cell therapy has achieved considerable progress in relapsed and refractory MM.Nevertheless,this therapy still has limitations such as cytokine release syndrome,neurotoxicity,and off-target effects.Natural killer (NK) cells,as a critical component of the innate immune system,play an essential role in tumor immunosurveillance.Therefore,CAR-modified NK (CAR-NK) cells are put forward as a therapeutic option for MM.The available studies have suggested that multiple targets can be used as specific therapeutic targets for CAR-NK cell therapy and confirmed their antitumor effects in MM cell lines and animal models.This review summarizes the anti-tumor mechanisms,biological characteristics,and dysfunction of NK cells in the MM tumor microenvironment,as well as the basic and clinical research progress of CAR-NK cells in treating MM.


Assuntos
Animais , Receptores de Antígenos Quiméricos/metabolismo , Mieloma Múltiplo/metabolismo , Células Matadoras Naturais/metabolismo , Imunoterapia Adotiva/métodos , Microambiente Tumoral
4.
Beijing Da Xue Xue Bao ; (6): 975-981, 2023.
Artigo em Chinês | WPRIM | ID: wpr-1010156

RESUMO

OBJECTIVE@#To investigate the regulatory effect of interferon-α (IFN-α) on the apoptosis and killing function of CD56dimCD57+ natural killer (NK) cells in systemic lupus erythematosus (SLE) patients, and to explore the specific mechanism.@*METHODS@#A total of sixty-four newly treated SLE patients and sixteen healthy controls (HC) enrolled in the Second Hospital of Dalian Medical University were selected as the research subjects. And the gene expression levels of molecules related to NK cell-killing function were detected by real-time quantitative polymerase chain reaction. CD56dimCD57+ NK cells were co-cultured with the K562 cells, and the apoptotic K562 cells were labeled with Annexin-Ⅴ and 7-amino-actinomycin D. Peripheral blood mononuclear cells were treated with 20, 40, and 80 μmol/L hydrogen peroxide (H2O2), and treated without H2O2 as control, the expression level of perforin (PRF) was detected by flow cytometry. The concentration of IFN-α in serum was determined by enzyme linked immunosorbent assay. The expression levels of IFN-α receptors (IFNAR) on the surface of CD56dimCD57+ NK cells were detected by flow cytometry, and were represented by mean fluorescence intensity (MFI). CD56dimCD57+ NK cells were treated with 1 000 U/mL IFN-α for 24, 48 and 72 h, and no IFN-α treatment was used as the control, the apoptosis and the expression levels of mitochondrial reactive oxygen species (mtROS) were measured by flow cytometry and represented by MFI.@*RESULTS@#Compared with HC(n=3), the expression levels of PRF1 gene in peripheral blood NK cells of the SLE patients (n=3) were decreased (1.24±0.41 vs. 0.57±0.12, P=0.05). Compared with HC(n=5), the ability of peripheral blood CD56dimCD57+ NK cells in the SLE patients (n=5) to kill K562 cells was significantly decreased (58.61%±10.60% vs. 36.74%±6.27%, P < 0.01). Compared with the control (n=5, 97.51%±1.67%), different concentrations of H2O2 treatment significantly down-regulated the PRF expression levels of CD56dimCD57+ NK cells in a dose-dependent manner, the 20 μmol/L H2O2 PRF was 83.23%±8.48% (n=5, P < 0.05), the 40 μmol/L H2O2 PRF was 79.53%±8.56% (n=5, P < 0.01), the 80 μmol/L H2O2 PRF was 76.67%±7.16% (n=5, P < 0.01). Compared to HC (n=16), the serum IFN-α levels were significantly increased in the SLE patients (n=45) with moderate to high systemic lupus erythematosus disease activity index (SLEDAI≥10) [(55.07±50.36) ng/L vs. (328.2±276.3) ng/L, P < 0.001]. Meanwhile, compared with HC (n=6), IFNAR1 expression in peripheral blood CD56dimCD57+ NK cells of the SLE patients (n=6) were increased (MFI: 292.7±91.9 vs. 483.2±160.3, P < 0.05), and compared with HC (n=6), IFNAR2 expression in peripheral blood CD56dimCD57+ NK cells of the SLE patients (n=7) were increased (MFI: 643.5±113.7 vs. 919.0±246.9, P < 0.05). Compared with control (n=6), the stimulation of IFN-α (n=6) significantly promoted the apoptosis of CD56dimCD57+ NK cells (20.48%±7.01% vs. 37.82%±5.84%, P < 0.05). In addition, compared with the control (n=4, MFI: 1 049±174.5), stimulation of CD56dimCD57+ NK cells with IFN-α at different times significantly promoted the production of mtROS in a time-dependent manner, 48 h MFI was 3 437±1 472 (n=4, P < 0.05), 72 h MFI was 6 495±1 089 (n=4, P < 0.000 1), but there was no significant difference at 24 h of stimulation.@*CONCLUSION@#High serum IFN-α level in SLE patients may induce apoptosis by promoting mtROS production and inhibit perforin expression, which can down-regulate CD56dimCD57+ NK killing function.


Assuntos
Humanos , Interferon-alfa/metabolismo , Perforina/metabolismo , Leucócitos Mononucleares/metabolismo , Peróxido de Hidrogênio/metabolismo , Interferon gama/metabolismo , Antígeno CD56/metabolismo , Células Matadoras Naturais/metabolismo , Lúpus Eritematoso Sistêmico
5.
Tumor ; (12): 854-865, 2023.
Artigo em Chinês | WPRIM | ID: wpr-1030336

RESUMO

Objective:To investigate the effect of solute carrier family 38 member 2(SLC38A2)on the cytotoxicity of natural killer(NK)cells against tumor cells. Methods:Real-time fluorescence quantitative PCR was used to detect the mRNA expression of different glutamine transporters(SLC38A2,SLC1A5,SLC7A5,SLC7A1 and SLC1A4)in natural killer(NK)cells under glutamine deficiency or the spleens of dieting mice.NK-92MI cells were infected with the recombinant lentivirus carrying SLC38A2 gene to construct SLC38A2-overexpressing NK cells.After SLC38A2 overexpression or increasing glutamine concentration,the lactate dehydrogenase releasing assay was used to detect the cytotoxicity of NK cells against pancreatic tumor cell PANC-1 and liver cancer cell HUH-7,and the apoptosis of two tumor cells was detected by flow cytometry assay after AnnexinV/7-AAD staining.Finally,the expression level of cell surface CD107a,a degranulation marker,as well as the expression of cytotoxic effectors interferon-γ(IFN-γ)and tumor necrosis factor-α(TNF-α),in NK cells was further investigated by flow cytometry. Results:The mRNA expression of glutamine transporter SLC38A2 was significantly upregulated in NK cells under glutamine deficient conditions and the spleens of dieting mice(P<0.001,P<0.01).SLC38A2-overexpressing NK-92MI cell model were successfully established.Overe-xpression of SLC38A2 or glutamine treatment could significantly increase the cytotoxicity of NK-92MI cells against pancreatic tumor cell PANC-1 and liver cancer cell HUH-7(P<0.05)and obviously promote the apoptosis of tumor cells(P<0.01).Flow cytometry analysis results showed that SLC38A2-overexpressing NK-92MI cells significantly increased CD1 07a expression on the cell surface and produced more IFN-γ and TNF-α when co-cultured with tumor cells(P<0.001). Conclusion:The amino acid transporter SLC38A2 can significantly enhance the cytotoxicity of NK cells against tumor cells.

6.
Acta Pharmaceutica Sinica B ; (6): 3093-3105, 2023.
Artigo em Inglês | WPRIM | ID: wpr-982892

RESUMO

Deficiency of natural killer (NK) cells shows a significant impact on tumor progression and failure of immunotherapy. It is highly desirable to boost NK cell immunity by upregulating active receptors and relieving the immunosuppressive tumor microenvironment. Unfortunately, mobilization of NK cells is hampered by poor accumulation and short retention of drugs in tumors, thus declining antitumor efficiency. Herein, we develop an acid-switchable nanoparticle with self-adaptive aggregation property for co-delivering galunisertib and interleukin 15 (IL-15). The nanoparticles induce morphology switch by a decomposition-metal coordination cascade reaction, which provides a new methodology to trigger aggregation. It shows self-adaptive size-enlargement upon acidity, thus improving drug retention in tumor to over 120 h. The diameter of agglomerates is increased and drug release is effectively promoted following reduced pH values. The nanoparticles activate both NK cell and CD8+ T cell immunity in vivo. It significantly suppresses CT26 tumor in immune-deficient BALB/c mice, and the efficiency is further improved in immunocompetent mice, indicating that the nanoparticles can not only boost innate NK cell immunity but also adaptive T cell immunity. The approach reported here provides an innovative strategy to improve drug retention in tumors, which will enhance cancer immunotherapy by boosting NK cells.

7.
Artigo em Chinês | WPRIM | ID: wpr-1025017

RESUMO

Natural killer(NK)cells as intrinsic immune cells kill tumor cells without the need for pre-stimulation by tumor antigens.Therefore,NK cell based immunotherapy has unique advantages and has made significant progress in tumor treatment.In this article,we review the development,classification,and mechanism of NK cells as well as the applications of NK cell based immunotherapies,including immune checkpoint inhibitors,adoptive cell therapy,and NK cell adapters in tumor immunity.Thus,we elucidate the principle,current status,and developmental trend of NK cell-based anti-tumor immunotherapies to provide ideas for their development and application in the field of tumor immunotherapy.

8.
Artigo em Chinês | WPRIM | ID: wpr-986524

RESUMO

Multiple myeloma is one type of hematological malignancy, characterized by the proliferation and accumulation of monoclonal plasma cells in bone marrow. Bone marrow microenvironment plays a key supporting role in the proliferation and survival of myeloma cells, where a large number of immune cells exist but are functionally suppressed. Based on the studies of myeloma immune microenvironment in recent years, we summarize the recent advances and existing problems in the treatment of multiple myeloma and put forward some considerations and suggestions, to provide references for researchers in this field.

9.
Artigo em Chinês | WPRIM | ID: wpr-923776

RESUMO

Objective To examine the effects of Toxoplasma gondii infection on the proportion, quantity, differentiation and function of mouse and human uterine natural killer cells (uNK cells), so as to explore the role of uNK cells in abortion of early pregnancy caused by T. gondii infection. Methods Pregnant mice were injected intraperitoneally with T. gondii tachyzoites on day 6.5 of pregnancy, and the abortion mouse model caused by T. gondii infections was constructed. Mouse uterine lymphocytes were isolated on day 9.5 of pregnancy. Human uterine lymphocytes were isolated from fresh human decidual specimens after abortion in normal early pregnancy and co-cultured with tachyzoites of the T. gondii RH strain for 48 h at T. gondii/uterine lymphocytes ratios of 0.5:1, 1:1 and 2:1. The phenotypes of mouse uNK cells (CD122, NK1.1, DX5) and human uNK cells (CD3, CD56, CD11b, CD27) and the expression of intracellular cytokines interferon-γ (IFN-γ) and tumor necrosis factor-α (TNF-α) were detected by flow cytometry. Mouse and human uNK cells were sorted by magnetic beads, and the cytotoxicity of uNK cells was tested using the lactate dehydrogenase (LDH) release assay at effector/target cell ratios of 1:1, 5:1, 10:1 and 20:1 with mouse or human uNK cells as effector cells and mouse YAC-1 cells or human K562 cells as target cells. Results On day 9.5 of pregnancy, the mouse abortion rate was significantly higher in the infected group than that in the control group (83.02% vs. 3.51%; χ2 = 71.359, P < 0.001). Significantly lower absolute number of uNK cells [(4 547 ± 1 610) cells/mouse vs. (8 978 ± 3 339) cells/mouse; U = 2.000, P < 0.05], lower NK1.1 expression on uNK cell surface [(74.53 ± 8.37)% vs. (93.00 ± 1.11)%; U = 0.000, P < 0.05], higher proportion of NK1.1-DX5-cells [(20.10 ± 8.03)% vs. (5.04 ± 0.68)%; U = 0.000, P < 0.05], lower proportion of NK1.1+ DX5+ cells [(21.70 ± 12.48)% vs. (45.75 ± 2.26)%; U = 0.000, P < 0.05] and higher IFN-γ expression [(16.74 ± 1.36)% vs. (8.13 ± 1.90)%; U = 0.000, P < 0.05] were detected in the infected group than in the control group, while no significant difference was seen in TNF-α expression between the two groups [(67.98 ± 9.20)% vs. (52.93 ± 10.42)%; U = 2.000, P > 0.05]. The mouse uNK cells showed a strong cytotoxicity in the infected group, and the cytotoxicity gradually increased with the effector/target cell ratio. The cytotoxicity of uNK cells against YAC-1 cells was 2.30%, 4.32%, 8.12% and 12.65% in the infected group and 1.21%, 1.63%, 2.51% and 3.22% in the control group at effector/target cell ratios of 1:1, 5:1, 10:1 and 20:1, respectively. Following co-culture of human uterine lymphocytes and tachyzoites of the T. gondii RH strain for 48 h, the proportion [TOX 2:1 group vs. control group: (6.61 ± 1.75)% vs. (17.48 ± 4.81)%; F = 7.307, P < 0.01], and absolute number of human uNK cells in uterine lymphocytes of human uNK cells in uterine lymphocytes [TOX 2:1 group vs. control group: (12 104 ± 5 726) cells/well vs. (65 285 ± 21 810) cells/well; H = 11.540, P < 0.01] were significantly lower in the infected group than in the control group. A lower proportion of CD56brightCD16- NK cells [TOX 2:1 group vs. control group: (25.25 ± 5.90)% vs. (36.03 ± 4.51)%; F = 3.213, P > 0.05] and higher proportion of CD56dimCD16+ NK cells [TOX 2:1 group vs. control group: (11.15 ± 2.15)% vs. (7.09 ± 2.24)%; F = 2.992, P > 0.05] were detected in uNK cells in the infected group than in the control group, and the ratio of CD56brightCD16- cells/CD56dimCD16+ cells was significantly lower in the infected group than in the control group [TOX2:1 group vs. control group: (2.37 ± 0.92) vs. (5.58 ± 2.39); H = 8.228, P < 0.05]. In addition, the proportion of CD11b+CD27- cells in human uNK cells was significantly higher in the infected group than in the control group [TOX 2:1 group vs. control group: (30.28 ± 6.91)% vs. (17.48 ± 4.67)%; H = 6.556, P < 0.05], while no significant differences were found between the two groups in terms of IFN-γ [TOX 2:1 group vs. control group: (14.13 ± 1.28)% vs. (15.19 ± 1.64)%; F = 1.639, P > 0.05] or TNF-α expression [TOX 2:1 group vs. control group: (54.76 ± 10.02)% vs. (50.33 ± 3.67)%; F = 0.415, P > 0.05]. Human uNK cells presented a strong cytotoxicity in the infected group, and the cytotoxicity gradually increased with the effector/target cell ratio. The cytotoxicity of human uNK cells against K562 cells was 11.90%, 28.11%, 49.91% and 73.35% in the infected group and 12.21%, 21.63%, 33.51% and 48.22% in the control group at effector/target cell ratios of 1:1, 5:1, 10:1 and 20:1, respectively. Conclusions T. gondii infection presents diverse effects on the differentiation and secretion ability of mouse and human uNK cells. However, T. gondii infection causes a reduction in the absolute number and enhances the cytotoxicity of both mouse and human uNK cells.

10.
Artigo em Chinês | WPRIM | ID: wpr-955222

RESUMO

Transplant rejection involves natural immune cells and acquired immune cells. For decades, acquired immune cells have been dominating the study of transplant immunity. Researchers have found the surprising new features of innate immune cells, including immune memory, which may be of great significance to further improve graft survival. The short-term survival rate of grafts is very good, but the long-term graft outcomes are less so and most transplants are eventually lost to chronic rejection in the clinic. In animal models and clinical studies, innate immune cells, especially macrophages and natural killer cells, often predominate the chronic rejection process which lead grafts lost. Recent studies suggest that innate immune cells are capable of acquiring adaptive features in that they either directly recognize the allografts or become "trained" in the allogeneic milieu to further acquire features of memory and donor specificity. In selected transplant models, targeting the adaptive features of innate immune cells has been shown to promote long-term graft survival. Clearly, these findings highlight new therapeutic opportunities in further improvement of transplant outcomes as well as in treatment of cancers and autoimmune diseases in the clinic. The authors summarize the literature reports, introduce the recent acquired response characteristics of natural immune cells, and stimulate researchers to carry out more exploration in this field by fully discussing the heterogeneity and plasticity of natural immune cell types and the outstanding problems in related field.

11.
Frontiers of Medicine ; (4): 79-90, 2021.
Artigo em Inglês | WPRIM | ID: wpr-880969

RESUMO

Natural killer (NK) cells, a type of cytotoxic lymphocytes, can infiltrate into ischemic brain and exacerbate neuronal cell death. Astragaloside IV (ASIV) is the major bioactive ingredient of Astragalus membranaceus, a Chinese herbal medicine, and possesses potent immunomodulatory and neuroprotective properties. This study investigated the effects of ASIV on post-ischemic brain infiltration and activation of NK cells. ASIV reduced brain infarction and alleviated functional deficits in MCAO rats, and these beneficial effects persisted for at least 7 days. Abundant NK cells infiltrated into the ischemic hemisphere on day 1 after brain ischemia, and this infiltration was suppressed by ASIV. Strikingly, ASIV reversed NK cell deficiency in the spleen and blood after brain ischemia. ASIV inhibited astrocyte-derived CCL2 upregulation and reduced CCR2


Assuntos
Animais , Ratos , Encéfalo , Histona Desacetilases , Células Matadoras Naturais , Saponinas/farmacologia , Triterpenos/farmacologia
12.
Artigo em Chinês | WPRIM | ID: wpr-1004605

RESUMO

The killer cell immunoglobulin-like receptor (KIR) is located in 100-200kb region of the leukocyte receptor complex (LRC) on chromosome 19. KIR, mainly expresses on the surface of natural killer (NK) cells, is divided into inhibitory and activated receptor in function. Tumor cells could evade the killing of NK cells by regulating down the expression of HLA molecules on the cell surface. KIR molecules regulate the killing effect of NK cells by combining with human leukocyte antigen (HLA) to conduct inhibitory and active signals. In recent years, KIR and its immune regulation on tumors have become a research hotspot. The article reviews the research progress of KIR and its association with tumors, especially the correlation between KIR and high incidence of nasopharyngeal carcinoma (NPC) in Guangdong and Guangxi of China.

13.
Beijing Da Xue Xue Bao ; (6): 721-727, 2021.
Artigo em Chinês | WPRIM | ID: wpr-942243

RESUMO

OBJECTIVE@#To explore the significance of lymphocytes in systemic sclerosis (SSc), by detecting the levels of T lymphocytes, B lymphocytes and natural killer (NK) cells, and analyzing the correlation between the lymphocytes and clinical laboratory indexes.@*METHODS@#The numbers and proportion of T, CD4+T, CD8+T, B, and NK cells were detected by flow cytometry in peripheral blood of 32 SSc patients who had taken immunosuppressive drugs and 30 healthy controls (HC). The comparison of the lymphocyte subsets in SSc with them in the HC groups, and the correlation between the lymphocytes and other clinical and laboratory indicators were analyzed by the relevant statistical analysis.@*RESULTS@#Compared with the HC group, the numbers of T, CD4+T, CD8+T, and NK cells in peripheral blood of SSc group, who had taken immunosuppressive drugs, were significantly decreased (P < 0.05). More-over, the proportion of NK cells in peripheral blood of the SSc group was also significantly lower than that in the HC group (P=0.004). In addition, all the lymphocyte subsets were decreased in peripheral blood of more than 65% of the SSc patients who had taken immunosuppressive drugs. Compared with CD4+T normal group, the positivity of Raynaud's phenomenon, erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) was significantly increased in CD4+T reduction group, respectively (P=0.024, P < 0.001, P=0.018). ESR was higher in CD8+T reduction group than CD8+T normal group (P=0.022). The prevalence of fingertip ulcer was significantly increased in B cell decrease group (P=0.019). Compared with NK cell normal group, the prevalence of fingertip ulcer was significantly increased in NK cell lower group (P=0.033), IgM was remarkablely decreased yet (P=0.049). The correlation analysis showed that ESR was negatively correlated with the counts of T lymphocytes (r=-0.455, P=0.009), CD4+T lymphocytes (r=-0.416, P=0.018), CD8+T lymphocytes (r=-0.430, P=0.014), B cells (r=-0.366, P=0.039).@*CONCLUSION@#The number of CD4+T, CD8+T, B, and NK cells significantly decreased in peripheral blood of SSc patients who had used immunosuppressive drugs, some lymphocyte subsets might be related with Raynaud's phenomenon and fingertip ulcer, and reflected the disease activity by negatively correlated with ESR and CRP; the numbers of lymphocyte subsets in peripheral blood should be detected regularly in SSc patients who had taken immunosuppressive drugs.


Assuntos
Humanos , Linfócitos B , Citometria de Fluxo , Células Matadoras Naturais , Subpopulações de Linfócitos , Escleroderma Sistêmico , Subpopulações de Linfócitos T , Linfócitos T
14.
Ghana Med. J. (Online) ; 55(2): 56-63, 2021.
Artigo em Inglês | AIM | ID: biblio-1337553

RESUMO

Malaria-endemic areas of the world are noted for high morbidity and mortality from malaria. Also noted in these areas is the majority of persons in the population having acquired malaria immunity. Though this acquired malaria immunity does not prevent infection, it resists the multiplication of Plasmodium parasites, restricting disease to merely uncomplicated cases or asymptomatic infections. Does this acquired malaria immunity in endemic areas protect against other diseases, especially outbreak diseases like COVID-19? Does malaria activation of innate immunity resulting in trained or tolerance immunity contribute to protection against COVID-19? In an attempt to answer these questions, this review highlights the components of malaria and viral immunity and explores possible links with immunity against COVID-19. With malaria-endemic areas of the world having a fair share of cases of COVID-19, it is important to direct research in this area to evaluate and harness any benefits of acquired malaria immunity to help mitigate the effects of COVID-19 and any possible future outbreaks


Assuntos
Humanos , COVID-19 , Imunidade Inata , Malária
15.
Gac. méd. Méx ; Gac. méd. Méx;156(3): 188-194, may.-jun. 2020. tab, graf
Artigo em Inglês, Espanhol | LILACS | ID: biblio-1249893

RESUMO

Resumen Introducción: Después de un trasplante de células progenitoras hematopoyéticas (TCPH), la reconstitución de las células natural killer (NK) es la principal barrera contra las infecciones virales. Objetivo: Determinar que el conocimiento sobre la cinética de la reconstitución de las células NK posterior al TCPH contribuye a un eficiente monitoreo del trasplante, lo que incrementa la posibilidad de éxito de este. Método: Se incluyeron 21 pacientes sometidos a TCPH, así como un grupo control de individuos clínicamente sanos. En diferentes momentos después del trasplante (intervalo de 21 a 670 días), mediante citometría de flujo se cuantificaron las células NK CD3− CD16+ CD56+ en muestras de sangre periférica. Resultados: La recuperación de las células NK ocurre entre los tres y seis meses y entre los 10 y 12 meses postrasplante; su número fue significativamente menor (en comparación con el grupo control) en el tiempo restante del monitoreo. Conclusiones: El primer periodo de recuperación de las células NK ocurre entre los tres y seis meses posteriores al trasplante. La reconstitución es transitoria y el número de células NK varía en los primeros años.


Abstract Introduction: After hematopoietic stem cell transplantation (HSCT), natural killer (NK) cells reconstitution is the main barrier against viral infections. Objective: To determine that the knowledge on the kinetics of NK cell reconstitution after HSCT contributes to transplant efficient monitoring, which increases the possibility of its success. Method: Twenty-one patients undergoing HSCT were included, as well as a control group of clinically healthy individuals. At different time points after transplantation (range of 21 to 670 days), CD3- CD16+ CD56+ NK cells were quantified by flow cytometry in peripheral blood samples. Results: NK cell recovery occurs at three to six months and 10 to 12 months post-transplantation; their number was significantly lower (in comparison with the control group) in the rest of the monitoring time. Conclusions: The first period of NK cell recovery occurs between three and six months after transplantation. Reconstitution is transient and the number of NK cells varies in the first years.


Assuntos
Humanos , Masculino , Feminino , Lactente , Pré-Escolar , Criança , Adolescente , Células Matadoras Naturais/citologia , Transplante de Células-Tronco Hematopoéticas/métodos , Fatores de Tempo , Estudos Prospectivos , Receptores de IgG , Complexo CD3 , Antígeno CD56 , Proteínas Ligadas por GPI , Citometria de Fluxo
16.
J Biosci ; 2020 May; : 1-10
Artigo | IMSEAR | ID: sea-214296

RESUMO

Natural killer (NK) cells have pivotal role in immunotherapy of human ovarian cancer (OC). AlthoughmicroRNAs (miRNAs) participate in dysfunction of NK cells, how and whether miR-140-3p regulates cytotoxicity of NK cells in OC are uncertain. miR-140-3p and mitogen activated protein kinase 1 (MAPK1)abundances were examined via quantitative real-time polymerase chain reaction or western blot. Tumornecrosis factor-a (TNF-a) and interferon-c (IFN-c) abundances were examined via enzyme linkedimmunosorbent assay. NK cytotoxicity to OC was evaluated via lactate dehydrogenase release. The relevanceof miR-140-3p and MAPK1 was proved via luciferase activity analysis. Murine xenograft experiment wasapplied to assess the function of miR-140-3p on NK cytotoxicity. miR-140-3p was elevated and MAPK1 wasdeclined in NK cells from OC patients, while the levels were reversed after treatment of interleukin-2 (IL-2).MiR-140-3p addition mitigated IFN-c and TNF-a production induced via IL-2 as well as NK-92 cytotoxicityto OC cells. Additionally, MAPK1 was negatively regulated via miR-140-3p and ablated the influence of miR140-3p on cytotoxicity, cytokines levels. Besides, miR-140-3p enrichment facilitated tumor growth via suppressing function of NK cells in a xenograft model. miR-140-3p suppressed NK cytotoxicity to OC cells viamediating MAPK1, indicating a new avenue of ameliorating NK cells function for OC treatment.

17.
Artigo em Chinês | WPRIM | ID: wpr-828939

RESUMO

OBJECTIVE@#To assess the effect of neutralizing CD96 on natural killer (NK) cell functions in mice with pulmonary infection and explore the possible mechanism.@*METHODS@#Male BALB/c mice were randomly divided into infection group (Cm group), anti-CD96 treatment group (anti-CD96 group) and control group (=5). In the former two groups, was inoculated intranasal administration to establish mouse models of pulmonary infection, and the mice in the control group received intranasal administration of the inhalation buffer. In anti-CD96 group, the mice were injected with anti-CD96 antibody intraperitoneally at the dose of 250 μg every 3 days after the infection; the mice in Cm group received intraperitoneal injections of saline. The body weight of the mice was recorded daily. The mice were sacrificed 5 days after infection, and CD96 expression was detected by quantitative real-time PCR and Western blotting. HE staining and pathological scores were used to evaluate pneumonia of the mice. The inclusion body forming units (IFUs) were detected in the lung tissue homogenates to assess lung tissue chlamydia load. Flow cytometry and ELISA were used to assess the capacity of the lung NK cells to produce interferon-γ (IFN-γ) and regulate macrophages and Th1 cells.@*RESULTS@# infection inhibited CD96 expression in NK cells of the mice. Compared with those in Cm group, the mice in antiCD96 mice showed significantly milder lung inflammation ( < 0.05) and reduced chlamydia load in the lung tissue ( < 0.05). Neutralizing CD96 with anti-CD96 significantly enhanced IFN-γ secretion by the NK cells ( < 0.05) and augmented the immunoregulatory effect of the NK cells shown by enhanced responses of the lung macrophages ( < 0.05) and Th1 cells ( < 0.05).@*CONCLUSIONS@#Inhibition of CD96 alleviates pneumonia in -infected mice possibly by enhancing IFN-γ secretion by NK cells and augmenting the immunoregulatory effect of the NK cells on innate and adaptive immunity.


Assuntos
Animais , Masculino , Camundongos , Antígenos CD , Infecções por Chlamydia , Chlamydia muridarum , Interferon gama , Células Matadoras Naturais , Lesão Pulmonar , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL
18.
Artigo em Chinês | WPRIM | ID: wpr-841552

RESUMO

Objective: To investigate the killing effect of amplified natural killer (NK) cells on the gastric cancer cells, and to elucidate its mechanism. Methods: The peripheral blood mononuclear cells (PBMCs) from 15 patients with gastric cancer were extracted and isolated. The morphology of NK cells before and after amplification was observed, the percentages of NK cells before and after amplification were detected, and the amplification time of NK cells after amplification was calculated. The killing effects of NK cells on the gastric cancer cells before and after amplification were detected. The percentages of expressions of killing activating receptors NKG2D and DNAM-1 and killing inhibitory receptors KIR2DL1 and KIR3DL1 were detected by flow cytometry. Results: Before amplification, the NK cells were round, small in size and scattered in distribution. After amplification, the NK cells were increased in size and irregular in shape. The percentage of NK cells after amplification was significantly higher than that before amplification ( P<.0. 01). and the number of the NK cells after amplification was (596 ± 152) times of before amplification. When the effective target ratio was 5 : 1. the killing activity of NK cells on the gastric cancer cells after amplification was significantly higher than that before amplification (P<0.01). After amplification, the percentages of expressions of killing activating receptors NKG2D and DNAM-1 were significantly higher than those before amplification ( P<0. 01). After amplification, the percentages of expressions of killing inhibitory receptors KIR2DL1 and KIR3DL1 were significantly lower than those before amplification (P<0.05). Conclusion: The killing effect of NK cells on the gastric cancer cells after amplification is stronger than before amplification. The mechanism may be related to increasing the expressions of activated receptors and decreasing the expressions of inhibitory receptors on the surface of NK cells after amplification.

19.
Bol. méd. Hosp. Infant. Méx ; 76(4): 188-192, jul.-ago. 2019. graf
Artigo em Espanhol | LILACS | ID: biblio-1089129

RESUMO

Resumen Introducción: Las neoplasias de células natural killer (NK) son poco frecuentes y representan <5% de todas las neoplasias linfoides. Comprometen diferentes entidades clínicas, como la leucemia de células NK, que es una neoplasia hematológica altamente agresiva con un pronóstico precario, que se presenta en hombres jóvenes y se observa con mayor frecuencia en ascendencia asiática. El virus de Epstein-Barr (VEB) parece estar relacionado con la patogenia de esta leucemia. Caso clínico: Se presenta el caso de un paciente de sexo masculino de 1 año y 7 meses de edad, quien inició su padecimiento con síndrome anémico, febril, infiltrativo e hiperleucocitosis. En el aspirado de médula ósea se detectaron blastos de morfología L2 (96%), inmunofenotipo CD56 (80.87%) y desoxinucleotidil transferasa terminal (84.11%). En la biopsia de médula ósea se identificó CD2+ membranoso, CD3+ citoplásmico y CD56+ membranoso; la serología para VEB fue positiva. El paciente recibió dos esquemas diferentes de quimioterapia basados en metotrexato, ifosfamida, etopósido, dexametasona y L-asparaginasa, y se documentó remisión parcial. Actualmente, se encuentra vivo con la enfermedad. Conclusiones: La leucemia de células NK es rara en adultos jóvenes, pero aún más en pacientes en edad pediátrica. Además, es de muy difícil tratamiento, ya que solo se cuenta con algunos reportes de casos, la sobrevida es de semanas a meses y las oportunidades de tratamiento se limitan. Recientemente, se ha evidenciado la utilidad del trasplante de médula ósea alogénico o células de cordón umbilical, y se ha logrado una sobrevida a 2 años. Las posibilidades terapéuticas en estos pacientes se encuentran en estudio. Se espera lograr en un futuro cercano la remisión completa y sobrevida a 5 años.


Abstract Background: Natural killer (NK) cell neoplasms are rare and represent <5% of all lymphoid neoplasms. They involve different clinical entities, of which one is NK cell leukemia, a highly aggressive hematologic neoplasm with poor prognosis that presents in young men and is more frequently seen in Asian descent. Epstein-Barr virus (EBV) seems to be related to the pathogenesis. Case report: A male patient of 1 year and 7 months of age, who began his condition with anemic, febrile, infiltrative syndrome and hyperleukocytosis is described. Bone marrow aspirate showed L2 morphology blasts (96%), CD56 (80.87%) and terminal deoxynucleotidyl transferase (84.11%) immunophenotype. Bone marrow biopsy showed membranous CD2+, cytoplasmic CD3+ and membranous CD56+; serology positive to EBV. The patient received two different chemotherapy schemes based on methotrexate, ifosfamide, etoposide, dexamethasone and L-asparaginase, which resulted in partial remission. Currently, the patient lives with the disease. Conclusions: NK cells leukemia is rare in young adults, but even more in pediatric patients, for which it is very difficult to treat because only a few cases have been reported in the literature, the survival varies from weeks to months and the chances of treatment are limited. Recently, the usefulness of allogeneic bone marrow transplantation or umbilical cord cells has been demonstrated, achieving a 2-year survival. The therapeutic possibilities in these patients are under study. In the near future, we hope to achieve the complete remission of the disease and a 5-year survival.


Assuntos
Humanos , Lactente , Masculino , Células Matadoras Naturais/metabolismo , Leucemia/tratamento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Indução de Remissão , Leucemia/diagnóstico , Leucemia/patologia , Herpesvirus Humano 4/isolamento & purificação
20.
Chin. med. j ; Chin. med. j;(24): 1305-1313, 2019.
Artigo em Inglês | WPRIM | ID: wpr-800846

RESUMO

Background@#Extranodal natural killer/T-cell lymphoma (ENKTL), nasal type, is an aggressive entity within the World Health Organization classification of lymphoid tumors. The International Prognostic Index is reported to be prognostically meaningful for ENKTL, but lacks discriminatory power for stage I/II ENKTL with extensive local invasion. This study aimed to evaluate the prognostic effects of local invasion by site and tissue type in patients with ENKTL.@*Methods@#We retrospectively analyzed data of 86 patients who were diagnosed with ENKTL by the Department of Pathology of Beijing Tongren Hospital from June 2002 to April 2016, and ascertained tumor infiltration of adjacent structures (AS), bone, and soft tissue for each patient, using physical findings and imaging scans. We used univariate and multivariate analysis to assess the association of each involved tissue or site with patients’ overall survival (OS).@*Results@#Of the 86 patients, 71(82.6%) experienced invasion of AS, 22(25.6%) of soft tissue, and 26(30.2%) had bone involvement. Overall, patients with AS involvement did not show significantly shorter survival than those without AS involvement (Log rank χ2 = 1.177, P = 0.278); however, patients who had involved eyeballs or brains showed significantly lower 2-year OS rates than those without eyeball involvement (Log rank χ2 = 4.105, P = 0.043) or brain involvement (Log rank χ2 = 7.126, P = 0.008). Patients with involved local soft tissue or bones, respectively, showed lower 2-year OS rates than those without involved local soft tissue (Log rank χ2 = 10.390, P = 0.001) or bones (Log rank χ2 = 8.993, P = 0.003). Multivariate analysis showed that involvement of the cheek or facial muscles (hazard ratio, HR = 5.471, 95% confidence interval [CI]: 1.466–20.416, P = 0.011) and the maxilla bone (HR = 6.120, 95% CI: 1.517–24.694, P = 0.011) were significantly independent predictors of lower 2-year OS rates.@*Conclusions@#Imaging can accurately detect ENKTL invasion of AS, soft tissue, and bone. Involvement of local soft tissue or bone was significantly associated with lower 2-year OS rates. Involvements of the cheek or facial muscle, as well as maxilla bone, are independent predictors of lower 2-year OS rates in ENKTL patients.

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