Expression Level of SOCS3 in Acute Lymphoblastic Leukemia Cells Affects the Cytotoxicity of NK Cells / 中国实验血液学杂志

OBJECTIVE@#To detect the expression level of suppressors of cytokine signaling 3 （SOCS3） in acute lymphoblastic leukemia (ALL), and to observe the effect of over-expresson of SOCS3 in Jurkat cells on the cytotoxicity of NK cells.@*METHODS@#The expression levels of SOCS3 mRNA in peripheral blood mononuclear cells of 20 children with ALL and 20 healthy children (normal control group) were detected by RT-PCR. The peripheral blood NK cells from healthy subjects were selected by immunomagnetic technique, and the purity was detected by flow cytometry. SOCS3 was overexpressed in Jurkat cells infected with lentivirus vector, and SOCS3 mRNA expression was detected by RT-PCR after lentivirus infection. The NK cells were co-cultured with the infected Jurkat, and LDH release method was used to detect the cytotoxicity of NK cells on the infected Jurkat cells. The concentrations of TNF-α and IFN-γ were determined by ELISA. The expression of NKG2D ligands MICA and MICB on the surface of Jurkat cells were detected by flow cytometry. Western blot was used to detect the effect of SOCS3 overexpression on STAT3 phosphorylation in Jurkat cells.@*RESULTS@#Compared with the control group, the mRNA expression of SOCS3 in the peripheral blood mononucleated cells of ALL children was significantly decreased. The purity of NK cells isolated by flow cytometry could reach more than 70%. The expression of SOCS3 mRNA in Jurkat cells increased significantly after lentivirus infection. Overexpression of SOCS3 in Jurkat cells significantly promoted the killing ability of NK cells and up-regulated the secretion of TNF-α and IFN-γ from NK cells. The results of flow cytometry showed that the expression of NKG2D ligands MICA and MICB on Jurkat cells increased significantly after SOCS3 overexpression. Western blot results showed that overexpression of SOCS3 significantly reduced the phosphorylation level of STAT3 protein in Jurkat cells.@*CONCLUSION@#SOCS3 mRNA expression was significantly decreased in ALL patients, and overexpression of SOCS3 may up-regulate the expression of MICA and MICB of NKG2D ligands on Jurkat cell surface through negative regulation of JAK/STAT signaling pathway, thereby promoting the cytotoxic function of NK cells.

Reconstitución de células natural killer después del trasplante de células progenitoras hematopoyéticas en niños / Natural killer cell reconstitution after hematopoietic stem-cell transplantation in children

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.

Human Leukocyte Antigen-C Genotype and Killer Immunoglobulin-like Receptor-Ligand Matching in Korean Living Donor Liver Transplantation

BACKGROUND: The interaction between killer immunoglobulin-like receptors (KIRs) and HLA class I regulates natural killer (NK) cell cytotoxicity and function. The impact of NK cell alloreactivity through KIR in liver transplantation remains unelucidated. Since the frequency of HLA-C and KIR genotypes show ethnic differences, we assessed the impact of HLA-C, KIR genotype, or KIR-ligand mismatch on the allograft outcome of Korean liver allografts. METHODS: One hundred eighty-two living donor liver transplant patients were studied. Thirty-five patients (19.2%) had biopsy-confirmed acute rejection (AR), and eighteen (9.9%) had graft failure. The HLA-C compatibility, KIR genotypes, ligand-ligand, and KIR-ligand matching was retrospectively investigated for association with allograft outcomes. RESULTS: Homozygous C1 ligands were predominant in both patients and donors, and frequency of the HLA-C2 allele in Koreans was lower than that in other ethnic groups. Despite the significantly lower frequency of the HLA-C2 genotype in Koreans, donors with at least one HLA-C2 allele showed higher rates of AR than donors with no HLA-C2 alleles (29.2% vs 15.7%, P=0.0423). Although KIR genotypes also showed ethnic differences, KIR genotypes and the number of activating KIR/inhibitory KIR were not associated with the allograft outcome. KIR-ligand mismatch was expected in 31.6% of Korean liver transplants and had no impact on AR or graft survival. CONCLUSIONS: This study could not confirm the clinical impact of KIR genotypes and KIR-ligand mismatch. However, we demonstrated that the presence of HLA-C2 allele in the donor influenced AR of Korean liver allografts.

Familial Hemophagocytic Lymphohistiocytosis Type 2 in a Korean Infant With Compound Heterozygous PRF1 Defects Involving a PRF1 Mutation, c.1091T>G

No abstract available.

Understanding of molecular mechanisms in natural killer cell therapy

Cancer cells and the immune system are closely related and thus influence each other. Although immune cells can suppress cancer cell growth, cancer cells can evade immune cell attack via immune escape mechanisms. Natural killer (NK) cells kill cancer cells by secreting perforins and granzymes. Upon contact with cancer cells, NK cells form immune synapses to deliver the lethal hit. Mature NK cells are differentiated from hematopoietic stem cells in the bone marrow. They move to lymph nodes, where they are activated through interactions with dendritic cells. Interleukin-15 (IL-15) is a key molecule that activates mature NK cells. The adoptive transfer of NK cells to treat incurable cancer is an attractive approach. A certain number of activated NK cells are required for adoptive NK cell therapy. To prepare these NK cells, mature NK cells can be amplified to obtain sufficient numbers of NK cells. Alternatively, NK cells can be differentiated and amplified from hematopoietic stem cells. In addition, the selection of donors is important to achieve maximal efficacy. In this review, we discuss the overall procedures and strategies of NK cell therapy against cancer.

Lymphocyte subsets in human immunodeficiency virus-unexposed Brazilian individuals from birth to adulthood

Ethnic origin, genetics, gender and environmental factors have been shown to influence some immunologic indices, so that development of reference values for populations of different backgrounds may be necessary. We have determined the distribution of lymphocyte subsets in healthy Brazilian individuals from birth to adulthood. Lymphocyte subsets were determined using four-colour cytometry in a cross-sectional study of 463 human immunodeficiency virus-unexposed children and adults from birth through 49 years of age. Lymphocyte subsets varied according to age, as previously observed in other studies. However, total CD4+ T cell numbers were lower than what was described in the Pediatric AIDS Clinical Trials Group P1009 (PACTG P1009), which assessed an American population of predominantly African and Hispanic backgrounds until the 12-18 year age range, when values were comparable. Naïve percentages and absolute values of CD8+ T cells, as assessed by CD45RA expression, were also lower than the PACTG P1009 data for all analysed age ranges. CD38 expression on both CD4+ and CD8+ T cells was lower than the PACTG P1009 values, with a widening gap between the two studies at older age ranges. Different patterns of cell differentiation seem to occur in different settings and may have characteristic expression within each population.

Rapid flow cytometry based cytotoxicity assay for evaluation of NK cell function.

Assessment of natural killer cells (NK-cell) cytotoxicity is used not only in research settings but is also important in diagnosis of various diseases. NK-cell cytotoxicity assays are based on measurement of target cells killed by cytotoxic cells analyzed either by chromium (51Cr) release assay or flow cytometry. Both these methods use peripheral blood mononuclear cells (PBMC) or pure NK-cell population and hence require large volume of blood sample which is difficult to obtain in pediatric patients and patients with cytopenia. Hence, a flow cytometric assay was designed to determine NK cell activity using whole blood, eliminating the need for isolation of PBMCs or pure NK cells. This assay is based on a dual fluorescent staining of target cells (K562 cell line). The DIOC18 dye labeled K562 cells are incubated with whole blood and then counterstained with 7-AAD enabling the measurement of dead target cell and then percent cytotoxicity is calculated. This study compared the NK cell cytotoxicity using PBMC and whole blood in clinically relevant samples. There was no significant difference between two assays in the measurement of lytic activity or in reproducibility in the repeated samplings of healthy individuals. The whole blood assay required less volume of blood and also less processing time as compared to PBMC assay. It was also validated by testing patients diagnosed with familial hemophagocytic lymphohistiocytosis expected to have low NK-cell activity. This assay is rapid, sensitive and reproducible and requires significantly less volume of blood which is important for clinical evaluation of NK-cell function.

Effects of Psychosocial Interventions on Cortisol and Immune Parameters in Patients with Cancer: A Meta-analysis

PURPOSE: This study was done to evaluate the effects of psychosocial interventions on cortisol and immune response in adult patients with cancer. METHODS: MEDLINE via PubMed, Cochrane Library CENTRAL, EMBASE, CINAHL and domestic electronic databases were searched. Twenty controlled trials (11 randomized and 9 non-randomized trials) met the inclusion criteria with a total of 862 participants. Methodological quality was assessed using the Cochrane's Risk of Bias for randomized studies and the Risk of Bias Assessment tool for non randomized studies. Data were analyzed using the RevMan 5.2.11 program of Cochrane library. RESULTS: Overall, study quality was moderate to high. The weighted average effect size across studies was -0.32 (95% CI [-0.56, -0.07], p=.010, I2=45%) for cortisol concentration, -0.62 (95%CI [-0.96,-0.29], p<.001, I2=0%) for T lymphocyte (CD3) and -0.45 (95%CI [-0.74, -0.16], p=.003, I2=0%) for Th lymphocyte (CD4) numbers. Psychosocial interventions were not effective for Tc lymphocyte (CD4), NK cell, monocyte, and cytokine response. CONCLUSION: Although these results provide only small evidence of successful immune modulation, they support the conclusion that psychosocial interventions can assist cancer patients in reducing emotional distress and improving immune response.

Implication of Early Lymphocyte Recovery after Allogeneic Hematopoietic Stem Cell Transplantation in Children with Leukemia

PURPOSE: The repopulating lymphocytes after allogeneic hematopoietic stem cell transplantation have an important role not only on the prevention of serious infections in the early transplantation period, but also on the killing of residual leukemic cells by graft-versus-leukemia effect. The aim of this study was to analyze the impact of lymphocyte recovery after allogeneic stem cell transplantation in children with hematologic malignancies. MATERIALS AND METHODS: We evaluated 69 children transplanted for acute lymphoblastic leukemia (ALL) (n=34), acute myeloid leukemia (AML) (n=26), chronic leukemia (n=7) and juvenile myelomonocytic leukemia (n=2) between 1996 and 2008 at the Chonnam National University Hospital, Korea. The patients were grouped based on absolute lymphocyte counts (ALC) or =500/microL at D+21 and D+30 after transplant. RESULTS: Patients with a High ALC at D+21 and D+30 had a faster neutrophil and platelet engraftment. The High at D+30 group had a better 5 year overall survival (71% vs. 53%, p=0.043) and event-free survival (72% vs. 53%, p=0.065) than the Low at D+30 group. The incidence of grade II-IV acute and chronic graft-versus-host disease (GVHD), and relapse rate did not differ by the ALC counts. However, the Low at D+30 group had a significantly increased risk for transplant-related mortality (p=0.019). The univariate analysis showed that the factors associated with decreased survival were a Low ALC at D+30, patients with high risk ALL, and grade II-IV aGVHD in patients with ALL and AML. CONCLUSION: Early posttransplant serial lymphocyte measurement would be a simple but useful method for predicting transplant outcomes.

Analysis of NK cells in peripheral blood and tumor infiltrating lymphocytes in cervical cancer patients / Análisis de la población de células asesinas naturales (NK) en sangre periférica y en linfocitos infiltrantes de tumor en pacientes con cáncer de cuello uterino

Objective: To understand the biologic and clinical importance of intratumoral natural killer cells CD16+CD56+CD3 and NKT CD16+CD56+CD3 cells in immune surveillance against cervical cancer. Methods: To understand the significance of NK (CD16+CD56+CD3-) and NKT (CD16+CD56+CD3-) in immune surveillance against cervical cancer, we analysed 39 peripheral blood and 30 biopsy samples from cervical cancer patients, and 40 peripheral blood and 5 biopsy samples from healthy women with normal cytology. The frequencies of NK and NKT and HLA-I expression in keratinocytes were analysed by flow cytometry. Results: In peripheral blood, a higher frequency of NK was observed in the patient group compared with the controls (p=0.002). However, this increase was not reflected in TILs (p=0,095). A significant reduction of HLA-I expression was observed in the patient group compared to the control group (p=0.019). A low number of NK infiltrated was observed in tumors of patients with HLA-I down regulation, but it was not significant (p=0.374). A low number of NK infiltration was associated with shorter survival, but it was not significant (p=0.275). Conclusions: Our results show that although in peripheral blood an increase in NK population was observed in patient group, this increase was not reflected in TILs. It is possible that this inefficient migration of NK´s into the tumor milieu could be related to the expression of immunosuppressive cytokines, in particular IL-10.

Objetivo: Entender la importancia biológica y clínica de las células intratumorales natural killer (NK) CD16+CD56+CD3- y de las células natural killer T (NKT) CD16+CD56+CD3- en la inmunovigilancia del cáncer de cuello uterino (CCU). Métodos: Para comprender el papel de las NK (CD16+CD56+CD3-) y de las células natural killer T (NKT) (CD16+CD56+CD3-) en la inmunovigilancia del CCU, se analizaron 39 muestras de sangre periférica (SP) y 30 biopsias de pacientes con CCU, así como de 40 muestras de SP y 5 biopsias de cuello uterino de mujeres con citología normal. Las frecuencias de NK y NKT y la expresión de HLA-I se analizaron por citometría de flujo. Resultados: Se observó una mayor frecuencia de NK en SP en el grupo de pacientes comparado con el grupo control (p = 0,002). Sin embargo, este aumento no se reflejó en TIL (p = 0,095). Una reducción significativa de HLA-I se observó en el grupo de pacientes (p = 0,019). Esta disminución se asoció una disminución en el número de NK, pero no fue significativa (p = 0,374). Un bajo número de NK se asoció con una menor supervivencia, pero no fue significativo (p = 0,275). Conclusiones: Nuestros resultados muestran que aunque en SP se observa un incremento de NK, este no se refleja en los TIL. Es posible que este tráfico ineficiente de células NK hacia el tumor esté alterado por la expresión de citoquinas inmunosupresoras, en particular IL-10.

Células con propiedades inmunoreguladoras y su impacto en la patogénesis de la sepsis / Cells with immunoregulatory properties and their impact in the pathogenesis of sepsis

Sepsis, defined as a systemic inflammatory response syndrome caused by an infection, is a significant cause of mortality worldwide. It is currently accepted that death associated to sepsis is due to an immune hyperactivation state involving the development of a broad proinflammatory response along with alterations in the coagulation system. It is now clear that besides the inflammatory events, the clinical course of sepsis is characterized by the development of an anti-inflammatory response that could lead to death in its attempt to balance the initial response. The purpose of this review is to summarize current mechanisms that explain the pathogenesis of sepsis, underlying the role that cells with immunoregulatory properties play during the course of this complex syndrome. A better understanding of these processes will contribute in the search of more successful therapeutic strategies.

El síndrome de respuesta sistémica consecuencia de una infección, denominado sepsis, constituye una causa significativa de muerte en el mundo. Históricamente se ha aceptado que la muerte por sepsis se debe a un estado de hiperactivación inmunológica, que implica el desarrollo de una vasta respuesta pro-inflamatoria acompañada de alteraciones en el sistema de coagulación. Ahora es claro que además de los sucesos inflamatorios, el curso clínico de la sepsis se caracteriza por el desarrollo de una respuesta anti-inflamatoria que busca contrarrestar la respuesta inicial, y es ésta finalmente en gran parte responsable de la muerte de los pacientes. El propósito de esta revisión es resumir los mecanismos actuales que explican la patogénesis de la sepsis, y específicamente el papel que desempeñan las subpoblaciones celulares con propiedades inmuno-reguladoras durante el curso de la enfermedad. El mejor entendimiento de estos procesos contribuirá a la búsqueda de estrategias terapéuticas más exitosas.

Study of natural killer and natural killer T cells in chronic hepatitis C infection

Natural killer [NK] and natural killer T [NKT] cells are components of the innate immune system, and participate in the inflammatory processes during hepatic diseases. Impaired activity of these cells is suggested to contribute to viral persistence and chronic infection in hepatitis C virus [HCV] infection. However, the exact mechanisms are not yet fully understood. To investigate the frequency of peripheral NK and NKT cells in patients with chronic HCV infection, as compared with healthy controls. Thirty patients with chronic hepatitis due to HCV infection were included. Patients with liver cirrhosis, HCV and hepatitis B virus co-infection, diabetes mellitus, or who received interferon therapy were excluded. In addition, 20 normal healthy individuals were included as controls. Assessment of the frequency of peripheral NK and NKT cells by flow cytometry was carried out for all individuals. Compared with controls, patients with HCV had significantly lower percentages of NK and NKT cells in peripheral blood. Among patients with HCV, NK and NKT cell percentages did not correlate significantly with serum transaminase levels. Defective innate immunity, as evidenced by reduced peripheral NK and NKT cell frequency, is observed in patients with chronic hepatitis C infection

Linfócitos CD4, CD8 e células NK no estroma da cérvice uterina de mulheres infectadas pelo papilomavírus humano / CD4 and CD8 T lymphocytes and NK cells in the stroma of the uterine cervix of women infected with human papillomavirus

INTRODUÇÃO: A resposta imune pode ser um elemento chave para a progressão ou remissão da infecção pelo papilomavírus humano (HPV) no estroma da cérvice uterina. Este estudo objetivou quantificar no estroma cervical a presença de linfócitos T CD4, CD8 e células NK, por imunohistoquímica, em lesões de alto e baixo grau em pacientes infectadas por HPV MÉTODOS: Utilizou-se 56 amostras de biópsia da estroma cervical, sendo 43 amostras positivas para DNA de HPV de alto risco oncogênico e com diagnóstico histopatológico de neoplasia intraepitelial cervical (NIC) de alto e baixo grau, ou negativa para lesão intraepitelial e malignidade (NILM), e 13 amostras de pacientes negativas para DNA de HPV com diagnóstico histopatológico NILM RESULTADOS: Maior quantidade de linfócitos T CD4 foi observada em amostras NIC II/III, carcinoma e NILM (p=0,04) e naquelas cuja carga viral esteve entre 10 e 1,000 RLU/PCB. O predomínio de linfócitos T CD8 ocorreu em maior proporção nas amostras NIC II/III (p=0,02) e em amostras com carga viral entre 100 e 1.000 RLU/PCB. As células NK prevaleceram nas amostras com lesões de baixo grau e com baixa carga viral CONCLUSÕES: Este estudo comprovou que nas fases iniciais da infecção, onde não há ainda alterações celulares de alto grau, não temos a presença de células que possam desencadear a fase efetora da resposta imune.

INTRODUCTION: Immune response might be a key element regarding the progression or regression of human papillomavirus (HPV) infection in the stroma of the uterine cervix. This study aimed to quantify the presence of CD4 and CD8 T lymphocytes and NK cells in the cervical stroma, by means of immunohistochemistry, in high and low grade lesions in patients infected by HPV METHODS: Fifty-six biopsy samples from the uterine cervix were used. Forty-three samples were positive for oncogenic high-risk HPV DNA and had a histopathological diagnosis of high and low-grade cervical intraepithelial neoplasia (CIN) or negative for intraepithelial lesion and malignancy (NILM); while the other 13 samples were negative for HPV DNA with a histopathological diagnosis of NILM RESULTS: Higher quantities of CD4 T lymphocytes were observed in CIN II/III, carcinoma and NILM samples (p = 0.04) and in those in which the viral load was between 10 and 1.000 RLU/PCB. CD8 T lymphocytes were predominant in CIN II/III samples (p = 0.02) and also in samples with viral loads between 100 and 1,000 RLU/PCB. NK cells predominated in samples with low-grade lesions and low viral load CONCLUSIONS: This study proved that in the initial stages of the infection, in which no high-grade cell abnormalities have yet occurred, no cells that might trigger the effector phase of the immune response.

Células natural killer endometriais: o que são? O que fazem? O que devemos saber? / Endometrial natural killer cells: what are they? What do they do? What do we need to know?

As células natural killer endometriais, também chamadas células natural killer uterinas, têm recebido especial atenção no campo da imunologia reprodutiva. Teorias que consideram alterações na resposta imune como uma causa de infertilidade conjugal e de falhas nos tratamentos de reprodução assistida têm ponderado um possível envolvimento negativo das células natural killer endometriais. As células natural killer são linfócitos que podem ser identificados no sangue periférico e no endométrio, apresentando diferenças fenotípicas e funcionais importantes. As células periféricas não se alteram com a fase do ciclo menstrual e implantação, sendo que as células natural killer endometriais apresentam variações durante o ciclo menstrual e período peri-implantacional, com menores concentrações durante a fase proliferativa e aumentando na segunda fase do ciclo. A célula natural killer endometriais participam nas várias fases da implantação, invasão trofoblástica, placentação e desenvolvimento fetal e no desenvolvimento da gestação humana até aproximadamente 20 semanas.

Endometrial natural killer cells have been given special attention in reproductive immunology. The relation between the endometrial natural killer cells and alterations in the immune response as a cause of couples infertility and failure in assisted reproduction treatment have been studied in several theories. Natural killer cells are lymphocytes that may be identified in peripheral blood and endometrium, with phenotypical and functional differences between them. Peripheral natural killer cells do not change with the menstrual cycle or implantation, as opposed to endometrial natural killer cells which present lower concentration in the proliferative phase and higher concentration in the luteal phase. Endometrial natural killer cells play an important role in the implantation, trophoblastic invasion, placentation, fetal development and development of the human pregnancies up to 20 weeks of gestation.

Clinical Utility of Chimerism Status Assessed by Lineage-Specific Short Tandem Repeat Analysis: Experience from Four Cases of Allogeneic Stem Cell Transplantation / 대한진단검사의학회지

Chimerism testing permits early prediction and documentation of successful engraftment, and also facilitates detection of impending graft rejection. In this study, we serially monitored chimerism status by short tandem repeat-based PCR in nucleated cells (NC), T cells and natural killer (NK) cells after myeloablative allogeneic stem cell transplantation (SCT). Four patients with myeloid malignancies showed discrepant chimerism results among those three fractions. Three patients had mixed chimerism (MC) of donor/host T cells at a time point around the onset of chronic graft-versus-host disease (GVHD). In two patients with disease relapse, MC of NK cells preceded a morphological relapse or NK cells showed a higher percentage of patient cells compared to NC. Therefore, our study shows that chimerism analysis in lineage-specific cells might be useful in predicting clinical outcome after allogeneic SCT in certain patients.

Analysis of Characteristics of Mononuclear Cells Remaining in the Leukoreduction System Chamber of Trima Accel(R) and Their Differentiation Into Dendritic Cells / 대한진단검사의학회지

BACKGROUND: We investigated the characteristics of the mononuclear cells remaining in the leukoreduction system (LRS) chambers of Trima Accel(R) in comparison with those of standard buffy coat cells, and evaluated their potential for differentiation into dendritic cells. METHODS: Twenty-six LRS chambers of Trima Accel(R) were collected after platelet pheresis from healthy adults. Flow cytometric analysis for T, B, NK, and CD14+ cells was performed and the number of CD34+ cells was counted. Differentiation and maturation into dendritic cells were induced using CD14+ cells seperated via Magnetic cell sorting (MACS(R)) Seperation (Miltenyi Biotec Inc., USA). RESULTS: Total white blood cell (WBC) count in LRS chambers was 10.8x108 (range 7.7-18.0x108). The median values (range) of proportions of each cells were CD4+ T cell 29.6% (18.7-37.6), CD8+ T cell 27.7% (19.2-40.0), B cell 5.5% (2.2-12.1), NK cell 15.7% (13.7-19.9), and CD14+ cells 12.4% (8.6-32.3) respectively. Although total WBC count was significantly higher in the buffy coat (whole blood of 400 mL) than the LRS chambers, the numbers of lymphocytes and monocytes were not statistically different. The numbers of B cells and CD4+ cells were significantly higher in the buffy coat than the LRS chambers (P<0.05). The median value (range) of CD34+ cells obtained from the LRS chambers was 0.9x10(6) (0.2-2.6x10(6)). After 7 days of cytokine-supplemented culture, the CD14+ cells were successfully differentiated into dendritic cells. CONCLUSIONS: The mononuclear cells in LRS chambers of Trima Accel(R) are an excellent alternative source of viable and functional human blood cells, which can be used for research purposes.

Immunostimulatory action of AC II--an ayurvedic formulation useful in HIV.

Immunostimulatory activity of AC II, a registered ayurvedic preparation prepared at Amala Ayurvedic Research Centre for treating HIV and AIDS is reported. AC II administration could significantly enhance the mitogen-induced proliferation of lymphocytes of spleen cells. It was also found to increase cell-mediated immune responses in normal and tumor-bearing control animals. Oral administration of AC II significantly enhanced Natural Killer cell activity in normal and tumor-bearing animals on the 7th day, which was observed earlier than the tumor-bearing control animals and normal animals. Antibody dependent cellular cytotoxicity (ADCC) was also increased in AC II treated normal and tumor-bearing animals. An early enhancement of antibody-dependent complement-mediated cytotoxicity was also observed by the administration of AC II in normal as well as tumor-bearing animals. Treatment with AC II elevated the levels of IL-2, TNF-alpha and IFN-gamma in normal mice. Administration of AC II was also found to increase the cytotoxic T lymphocyte production in EL4 treated mice. These studies support the use of this immune stimulatory preparation in HIV patients.

Modulation of the Surface Expression of CD158 Killer Cell Ig-like Receptor by Interleukin-2 and Transforming Growth Factor-beta

Killer cell Ig-like receptor (KIR) binds to HLA class I molecules on the surface of target cells, and it confers inhibitory signals to NK cells. Although NK cytotoxicity can be affected by the change of the surface expression of KIR on NK cells, the effect of cytokines on the regulation of KIR expression has not been thoroughly investigated. Here in our study, we investigated the effect of several cytokines, including IL-2, TGF-beta, IFN-gamma, IL-12 and IL-18, on the surface expression of CD158 KIR, which binds to HLA-C, by the use of FACS analysis. In the isolated NK cells, IL-2 obviously increased the surface expression of CD158 KIR after 72 hr in vitro culture, and this was evidenced by the increased percentage of CD158+ NK cells and the increased mean fluorescence intensity of CD158 in CD158+ NK cells. In contrast, TGF-beta decreased the surface expression of CD158 KIR after 72 hr culture. However, IFN-gamma, IL-12 and IL-18 did not change the expression of CD158 KIR. The modulated expression of KIR by IL-2 and TGF-beta can be associated with the changed NK-cytotoxic target-discriminating ability of NK cells upon their exposure to IL-2 and TGF-beta.

Lymphocyte and NK cell subpopulations in HIV seronegative Thais.

Lymphocyte subpopulations, i.e. T, B and natural killer (NK) cells including NK cell subsets which express CD16 molecules (with or without co-expression of CD56 molecules) and NK cell subsets which express CD56 molecules (with or without co-expression of CD16 molecules) were enumerated by two color-flow cytometry in a total of 125 HIV seronegative Thai adults. The study demonstrated relatively low CD4 counts in the subjects, i.e. 26.3% of them had a CD4 count of less than 500 cells/microl. In contrast, their NK cell counts were relatively high. Statistical analyses of the percentage values showed that females had significantly higher CD3 (total T cells), but lower NK cell counts as compared to males (p < 0.05). Regarding age variation, an increase of 1.1% of CD4 cells per decade was seen. It was roughly estimated that about 86% of NK cells harbored both CD16 and CD56 molecules. Collective data from several studies including the present one suggest that high NK cell counts may be a compensation for low CD4 cell counts in Mongoloid people. Thus, the role of NK cells in the defense cascade against viral infections, especially human immunodeficiency virus infections deserves further investigation.