Presence Of Recombinant Human Interleukin-2 Research Articles

Stability and inhibitory function of Treg cells under inflammatory conditions in vitro.

Immunotherapy with transplanted T-regulatory (Treg) cells is currently in use. However, patients have complex internal environments with confounding factors, including the presence of inflammatory cytokines. The present study aimed to detect Treg cell function under simulated inflammatory conditions to provide a foundation for Treg cell-based immunotherapy. CD4+CD25high Treg cells were sorted from peripheral blood mononuclear cells and cultured for 14 days in the presence of recombinant human interleukin-2 (rhIL-2) and anti-CD3/CD28 beads, with or without 25 ng/ml rhIL-6. Next, the absolute count of Treg cells was determined, the stability and activity were detected by measuring the expression levels of forkhead box (Fox)P3 and CD39, and the suppressive function of Treg cells was investigated by assessing the suppression of T-effector cell proliferation by Treg cells after co-culture for 5 days. The number of Treg cells cultured in the presence of 25 ng/ml rhIL-6 for 14 days was reduced by 49.7% when compared with that of cells cultured without rhIL-6. Of the Treg cells continually cultured for 14 days without or with 25 ng/ml rhIL-6, 56.15 and 24.7% expressed FoxP3, respectively. There was no difference in the activity of the FoxP3+ Treg cells after culture for 14 days without or with 25 ng/ml rhIL-6. The suppressive function of Treg cells tended to deteriorate in the presence of rhIL-6. In conclusion, IL-6 inhibited the proliferation and stability of Treg cells, suggesting that administration of increased numbers of Treg cells may be required during Treg cell-based immunotherapy.

Clinical Study of Autologous Cytokine-Induced Killer Cells for the Consolidation Treatment of Elderly Patients with Diffuse Large B-Cell Lymphoma

Cytokine-induced killer (CIK) cells are activated T cells with natural killer (NK) properties that can be expanded in vitro in presence of recombinant human interleukin-2 (rhIL-2) starting from peripheral blood mononuclear cells stimulated by interferon-γ and anti-CD3 antibody. They express CD3 and CD56 as well as the NKG2D antigen and show major histocompatibility complex (MHC)–unrestricted cytotoxicity toward neoplastic but not normal targets. CIK cells express several chemokine receptors, and in vivo models suggest that they can migrate to the site of tumors after intravenous administration, there carrying out their cytotoxic potential and helping to control tumor growth. CIK cells have shown cytotoxic activity in vitro and in vivo against hematopoietic neoplastic cells, including AML (acute myeloid leukemia), CML (chronic myelogenous leukemia), and CLL (chronic lymphocytic leukemia). Their cytotoxicity against patient with B-NHL (B-cell non-Hodgkin lymphoma) , however, has not been fully investigated. The elderly population is susceptible to haematological malignancies, and these elderly patients are intolerant to cytotoxic drugs. Therefore, the exploration of a safe and reliable strategy reduse dose of chemotherapy is critical in improving the prognosis of elderly patients with haematological malignancies. To evaluate the effectiveness and safety of autologous cytokine-induced killer (CIK) cells for consolidation treatmemt in elderly patients with diffuse large B-cell lymphoma. Peripheral blood mononuclear cells (PBMC) were isolated from 20 elderly patients with diffuse large B-cell lymphoma. PBMCs were augmented by priming with interferon gamma (IFN-γ) followed by IL-2 and monoclonal antibody (mAb) against CD3. Autologous CIK cells (range 5 × 10(9)-1 × 10(10)) were then infused back to individual patients. The regimen was repeated every 4 weeks. The host cellular immune function, tumour-related biological parameters, imaging characteristics, disease condition, quality of life and survival time were assessed. Fourteen patients received 6 cycles of transfusion and 6 received 4 cycles. After treatment of CIK cells plus IL-2, the general conditions of 20 patients were to different extent improved No adverse effects were observed. The percentages of CD3(+), CD3(+) CD8(+) and CD3(+) CD56(+) cells were significantly increased (p < 0.05), and the levels of serum β2 microglobulin and lactate dehydrogenase (LDH) were markedly decreased (p < 0.05) after autologous CIK cell transfusion. Cancer-related symptoms were profoundly alleviated, as demonstrated by the improved quality of life (p < 0.01)., Complete remission(CR) observed in 11 patients before the treatmemt of CIK was still CR; Partial remission(PR) in 9 patients ,After the treatmemt of CIK, the transformation of disease state from partial remission to complete remission was seen in 4 patients. At the end of follow-up, the mean survival time was 24 months. Transfusion with autologous CIK cells is safe and effective for treating haematological malignancies in elderly patients. DisclosuresNo relevant conflicts of interest to declare.

Isolation of Koala Retroviruses from Koalas in Japan

Koala retrovirus (KoRV) is considered to be associated with leukemia, lymphoma and immunodeficiency-like diseases in koalas. We therefore conducted a pilot study of KoRV infection in five Queensland koalas in Kobe Municipal Oji Zoo. By polymerase chain reaction to detect partial env and pol genes of KoRV in genomic DNA isolated from whole blood and feces, all five koalas were found to be positive for KoRV proviruses. We succeeded in culturing koala lymphocytes from less than 1 ml blood for over 14 days in the presence of recombinant human interleukin-2. By coculturing the lymphocytes with human embryonic kidney (HEK) 293T cells, we isolated KoRVs from all five koalas. We designated these isolates as strains OJ-1 to OJ-5. By electron microscopy, we observed C-type retroviral particles in HEK 293T cells chronically infected with KoRV strain OJ-4. This is the first report on the isolation of KoRV from koalas in a Japanese zoo.

Functional evaluation of ex vivo expanded cord blood lymphocytes

To examine the possibility of adoptive cellular immunotherapy such as donor lymphocyte infusion using ex vivo expanded cord blood (CBL) lymphocytes, the potential expansion ability of CBL lymphocytes and the function of expanded CBL lymphocytes were evaluated.Mononuclear cell fractions derived from CBL or peripheral blood (PBL) were placed in anti-CD3 monoclonal antibody-coated flasks and cultured in the presence of recombinant human interleukin-2 for 4 days. Cells then were transferred to noncoated flasks and cultured for another 2 weeks. On day 14, polyclonality, cell surface markers, killer activity, and intracellular cytokine profiles were evaluated.Cells were polyclonally expanded. The differences in cumulative fold expansion on day 14 between CBL [1174 +/- 637 (292-1939), n = 6] and PBL [1247 +/- 568 (517-2328), n = 9] were not significant (p = 0.95). Phenotypic patterns of both expanded CBL and PBL were similar. CD4/CD8 ratio of expanded CBL appeared to remain greater than 1 on day 8. In contrast, that of expanded PBL became less than 1. In both cases, approximately 20% of cells had the CD3(+)CD8(+)CD56(+) phenotype. At an effector to target ratio (E/T) of 40:1, the natural killer activity of expanded CBL (64.5% +/- 10.8%, n = 9) was significantly higher than that of expanded PBL (48.3% +/- 16.8%, n = 9) (p < 0.01, Mann-Whitney U-test). However, there was no significant difference in lymphokine-activated killer activity between expanded CBL (45.3% +/- 25.2%, n = 7) and expanded PBL (67.2% +/- 12.3%, n = 7). Interferon-gamma-producing cells were dominant in both cases.It was feasible to achieve approximately 1000-fold expansion of CBL, and the phenotype and function of expanded CBLs were essentially equivalent to those of expanded PBL. This suggested that ex vivo expanded CBL may be applied to adoptive cellular immunotherapy such as donor lymphocyte infusion.

CD4+ Epstein–Barr Virus-Specific Cytotoxic T-Lymphocytes from Human Umbilical Cord Blood

Umbilical cord blood (CB) is increasingly used for allogeneic hematopoietic stem cell transplantation. To determine whether viral antigen-specific cytotoxic T-lymphocytes (CTL) could be generated from the predominantly naive T-cell populations in CB, CB-derived mononuclear cells were stimulated with autologous Epstein–Barr virus (EBV) transformed B-lymphoblastoid cell lines over several weeks in the presence of recombinant human interleukin-2 (IL-2). By 28 days of culture, T-lymphocytes from all six CB that had been treated with IL-2 displayed EBV-specific cytotoxicity. These cells were largely CD4+, with complete inhibition of cytotoxicity by anti-CD3 and variable inhibition by anti-HLA DR monoclonal antibodies. The EBV-specific effectors were cloned by limiting dilution, and most of the CTL clones were CD4+. The cytotoxicity of the CB-derived CD4+ CTL clones was inhibited by EGTA but not by anti-Fas ligand mAb, suggesting that this cytotoxicity was mediated by perforin/granzyme B. These data indicate that virus-specific CTL can be cultivated and cloned from CB, a human T-cell source that may not have prior in vivo antigenic exposure or reactivity. This finding may have applications in adoptive immunotherapy to recipients of CB transplants.

Pentoxifylline Inhibits Integrin-Mediated Adherence of Interleukin-2–Activated Human Peripheral Blood Lymphocytes to Human Umbilical Vein Endothelial Cells, Matrix Components, and Cultured Tumor Cells

Peripheral blood lymphocytes (PBLs) cultured in the presence of recombinant human interleukin-2 (rhIL-2) develop a natural killer (NK) cell phenotype (CD16+, CD56+, CD3-) and are referred to as lymphokine-activated killer cells (LAK). In developing the LAK phenotype, enhanced adherence to matrix components and endothelial cells have been described. In this report we investigated the functional behavior of adhesion receptors in rhIL-2-activated PBLs by in vitro adhesion assay and by flow cytometry. Compared to PBLs, IL-2-activated PBLs had increased integrin-mediated adherence to: (1) fibronectin (FN), (2) human umbilical vein endothelial (HUVE) cells, and (3) cultured melanoma and pancreatic tumor cell lines. This increase in adherence was mediated by increased surface expression of members of the beta 1 and beta 2 integrin subfamilies, as determined by flow cytometric analysis. No induction of an activation-dependent beta 1 (CD29) epitope was detected. We also investigated the effects of the methylxanthine derivative pentoxifylline (PTX) on PBLs and rhIL-2-activated PBL adhesion. PBLs co-cultivated in the presence of rhIL-2 (1,000 U/mL) and PTX exhibited reduced adherence to FN, HUVE and cultured tumor cell lines. This inhibition by PTX was concentration- and time-dependent. The increased expression of integrins induced by rhIL-2 was only in part inhibited by PTX, suggesting that PTX induced a subpopulation of integrins that are expressed but functionally inactive.

Pentoxifylline inhibits integrin-mediated adherence of interleukin-2- activated human peripheral blood lymphocytes to human umbilical vein endothelial cells, matrix components, and cultured tumor cells

Peripheral blood lymphocytes (PBLs) cultured in the presence of recombinant human interleukin-2 (rhIL-2) develop a natural killer (NK) cell phenotype (CD16+, CD56+, CD3-) and are referred to as lymphokine- activated killer cells (LAK). In developing the LAK phenotype, enhanced adherence to matrix components and endothelial cells have been described. In this report we investigated the functional behavior of adhesion receptors in rhIL-2-activated PBLs by in vitro adhesion assay and by flow cytometry. Compared to PBLs, IL-2-activated PBLs had increased integrin-mediated adherence to: (1) fibronectin (FN), (2) human umbilical vein endothelial (HUVE) cells, and (3) cultured melanoma and pancreatic tumor cell lines. This increase in adherence was mediated by increased surface expression of members of the beta 1 and beta 2 integrin subfamilies, as determined by flow cytometric analysis. No induction of an activation-dependent beta 1 (CD29) epitope was detected. We also investigated the effects of the methylxanthine derivative pentoxifylline (PTX) on PBLs and rhIL-2-activated PBL adhesion. PBLs co-cultivated in the presence of rhIL-2 (1,000 U/mL) and PTX exhibited reduced adherence to FN, HUVE and cultured tumor cell lines. This inhibition by PTX was concentration- and time-dependent. The increased expression of integrins induced by rhIL-2 was only in part inhibited by PTX, suggesting that PTX induced a subpopulation of integrins that are expressed but functionally inactive.

Factors influencing the establishment of tumour-infiltrating lymphocyte cultures from human breast carcinoma and colon carcinoma tissue

Tumour-infiltrating lymphocytes (TIL) were obtained from breast and colon tumour tissue and cultured in vitro in the presence of recombinant human interleukin-2. Seven of 35 breast tumours and five of 41 colon TIL cultures were established in vitro: proliferation rates of greater than 10 3 were achieved. The cytotoxic capacity of these cells was determined against the cell lines K562 and SW742, and percentage cytotoxicity levels of greater than 97% and 79%, respectively, were seen. An inverse relationship between the ability of TIL to kill and their proliferative capacity was observed in all cultures. The prominant phenotype was CD3 positive, with greater than 55% of TIL expressing this antigen; there was no expression of CD16. The expression of CD56 and CD25 varied, being maximumly expressed on 64% and 38% of TIL, respectively. When greater than 90% of TIL expressed CD3, the ability of the culture to kill the target cell lines was low; only when there was an increase in the proportion of cells expressing CD56 and a decrease in the expression of CD3 was there high cytotoxicity. This study indicates that the TIL which proliferate in vitro in the presence of interleukin-2 are not necessarily the mediators of cytotoxicity.

Development of a new culture system for human lymphokine-activated killer cells

We have developed a new culture system (termed the JCC device) for the generation and expansion of human lymphokine-activated killer (LAK) cells. The JCC device was essentially based on dialysis culture. A dialysis membrane divided the culture vessel from the outside circulation of basal medium. Human lymph node lymphocytes were cultured in the culture vessel using a culture of 100 ml at an initial cell density of 1 × 10 6/ml in the presence of recombinant human interleukin-2. The culture vessel was rotated for the proper dispersion of cells. The cell density reached up to 1.2 × 10 7/ml on day 17 of culture. A modified JCC device supplying oxygen through a silicon tube prevented oxygen depletion in the culture vessel. With this modified JCC device cell densities up to 4.3 × 10 7/ml were achieved without reduction of cytolytic activity. Cell viability was more than 90% throughout the culture. The use of this JCC device permitted the culturing of LAK cells at a high cell density. The procedure is relatively cheap, simple and less time consuming than previous methods.

Autologous tumor-specific cytotoxic T-lymphocytes in a child with neuroblastoma

Activation of peripheral blood lymphocytes from a neuroblastoma patient by co-cultivation with autologous neuroblastoma cells in a mixed lymphocyte-tumor cell culture (A-MLTC) resulted in the generation of cytotoxic activity against the autologous neuroblastoma cell line HNB-MS. A-MLTC was set up in the presence of recombinant human interleukin-2 (IL-2). HNB-MS stimulator was treated with recombinant human interferon-γ (IFN-γ) prior to A-MLTC. CTL generated in short-term culture effectively lysed HNE-MS, while they had no effect on an Epstein-Barr virus transformed autologous B-cell line EB-MS. Moreover, CTL lysed 3 different allogeneic neuroblastoma cell lines, but not a rhabdomyosarcoma cell line RBB. Recombinant human tumor necrosis factor-α (TNF-α) and interleukin-4 (IL-4) enhanced and suppressed CTL generation, respectively, when added to the A-MLTC from the beginning of culture. CD3 + CD4 − CD8 + T cells were the major anti-tumor effectors. Furthermore, 111indium-labeled CTL clearly accumulated in metastatic sites. These results indicate that CTL can be used for adoptive immunotherapy in neuroblastoma. neuroblastoma-specifie CTL / IL-2 receptor

Cloned long-term cytolytic T-lymphocyte line with specificity for an immediate-early membrane antigen of murine cytomegalovirus.

Long-term cytolytic T-lymphocyte (CTL) lines that are specific for distinct antigens associated with different phases of the replicative cycle of the murine cytomegalovirus (MCMV) were established by cloning of CTL lines derived from lymph nodes of latently infected BALB/c mice. Two CTL clones were characterized in detail. Both displayed the Lyt-2+, L3T4- surface phenotype, and the recognition of their respective target antigens was class I (DLd) major histocompatibility complex antigen restricted. Clone S1 was specific for a structural antigen of MCMV, and clone IE1 detected an MCMV-specified immediate-early (IE) membrane antigen. Clone IE1 retained lytic activity, antigen specificity, and self-restriction after prolonged propagation in the presence of recombinant human interleukin-2 without restimulation by antigen. This interleukin-2-dependent line of the clone IE1, line IE1-IL, can serve as a reference line for the definition of the antigenic determinant IE1 of an IE membrane antigen.