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Aim: Active immunotherapy provides better recognition of tumor-related antigens by immune system of patient, enhanced immune system and elimination of malignant cells. This modality employs therapeutic potential of donor specific and tumor specific immune responses. Active immunotherapy targets immunosuppressive and tolerogenic mechanisms suppressed by tumor cells. T lymphocytes and antigen-presenting cells (dendritic cells) are two cell lineages that play crucial role in the battle of organism against cancer. Close similarity between cancer cells and normal cell structure is the most important reason of escape from defense cells, namely T lymphocytes. Stimulation and enhancement of T lymphocytes against cancer cells comprise principal part of therapy. Material and Method: To generate allogeneic dendritic cells, leukemic stem cells were isolated from bone marrow samples from patients with acute leukemia. Lysate was prepared from leukemic stem cells identified by flow cytometer. Stem cells and mononuclear cells (1x10>6/kg) obtained from sibling donors by apheresis were separated to produce Dendritic Cells. For Dendritic Cell transformation, GM-CSF and IL-4 were added to media where leukemic stem cell lysate from patient and mononuclear cells from sibling donor were treated. From samples taken from the culture medium, after 48, 72 and 96 hours, dendritic cell surface markers (CD 80, CD 83 and CD 86) was assessed by flow cytometry. CD3, CD14, CD19, CD56, CD66b-negative, and HLA-DR, CD86 positive are indicative of immature DC. HLA-DR, CD 80 and CD83 positive are indicative of mature DC. Results: Mononuclear cells were detected by 27 % among allogeneic hematopoietic cell groups harvested by apheresis. After culture under GMP conditions, mononuclear cell rate was found to be 24% on hours 96 and 120. It was seen that 88% of mononuclear cells transformed to mature dendritic cells after 96 hours culture. Conclusion: In cancer patients, minimal residual disease can be eliminated by active tumor vaccine after reducing tumor burden by standard methods. Tumor vaccine obtained from allogeneic sibling donor can be used in lieu of autologous tumor vaccine and it is thought to be more effective. Allogeneic dendritic cells produced at 37¡C in CO2 media under GMP conditions can be used in tumor immunotherapy. More effective method would have been used by employing dendritic cells against cancer stem cells rather than cancer cells itself. Figure Mature dendritic cells (CD83+) Figure. Mature dendritic cells (CD83+) Disclosures No relevant conflicts of interest to declare.

Background: Febrile neutropenia is very severe and urgent early complication after bone marrow transplantation before engraftment. Infection delays engraftments in these periods. Aim: In this study we evaluated the effect and outcome of granulocyte transfusion on febrile neutropenia and neutrophil engraftment in patients receiving allogeneic transplantation. The reasons for the use of the granulocyte transfusion were prolonged febrile neutropenia episode. Methods: Between 2015-2017, 16 patients receiving allogeneic bone marrow transplantation (BMT) were treated with granulocyte transfusion at the time of febrile neutropenia before engraftment. Sixteen patients (9 AML, and 7 ALL) underwent allogeneic transplantation. Nine of them transplanted from match sibling donors, 1 from unrelated donor, and 6 from mismatch family donor (haploidentic transplantation). They had febrile neutropenia after transplantation, before engraftment. They were given antimicrobial therapy. Granulocyte was collected from unrelated and same blood groups donors. We started granulocyte transfusion for 3-4 days. Results: Mean infused granulocyte counts were 3 × 1010 (1.2-4.8 × 1010)/d, and about 15%-20% of transfused granulocyte was monocyte. Before the granulocyte transfusion, on the 12th to 19th days of transplantation, their neutrophil counts were 0.02-0.09 × 103/dL. Twenty-four hours after granulocyte transfusion, mean neutrophil counts were 0.7 × 103/dL (0.4-1.2 × 103/dL). Neutrophil counts were 2.2 × 103/dL (1.7-2.6 × 103/dL) after 48 hour. After 72 hours, neutrophil counts were 3.2 × 103/dL (2.0- 4.6 × 103/dL). After 4th days of granulocyte transfusion, neutrophil counts were normal level (>0.5 × 103/dL) in 12 patients, and less than normal level (<0.5 × 103/dL) in 4 patients. Conclusion: Granulocyte transfusions during the febrile neutropenia, helped to better overcome febrile neutropenia periods in allogeneic transplant patients before engraftment. In addition, granulocytes transfusion also may help early neutrophil engraftments. The useful effect of granulocyte transfusion on neutrophil engraftment may be cause of cytokine (G-CSF) injection to donor before collection of granulocyte. Increased cytokine (G-CSF–GM-CSF–IL-3) level of transfused neutrophil and monocyte can also effect the neutrophil engraftment.

Background: Active immunotherapy provides better recognition of tumor-related antigens by immune system of patient, enhanced immune system and elimination of malignant cells. This modality employs therapeutic potential of donor specific and tumor specific immune responses. Active immunotherapy targets immunosuppressive and tolerogenic mechanisms suppressed by tumor cells. Aim: T lymphocytes and antigen-presenting cells (dendritic cells) are 2 cell lineages that play crucial role in the battle of organism against cancer. Close similarity between cancer cells and normal cell structure is the most important reason of escape from defense cells, namely T lymphocytes. Stimulation and enhancement of T lymphocytes against cancer cells comprise principal part of therapy. Methods: To generate allogeneic dendritic cells, leukemic stem cells were isolated from bone marrow samples from patients with acute leukemia. Lysate was prepared from leukemic stem cells identified by flow cytometer. Stem cells and mononuclear cells (1 × 10 > 6/kg) obtained from sibling donors by apheresis were separated to produce dendritic cells. For dendritic cell transformation, GM-CSF and IL-4 were added to media where leukemic stem cell lysate from patient and mononuclear cells from sibling donor were treated. From samples taken from the culture medium, after 48, 72 and 96 hours, dendritic cell surface markers (CD80, CD83 and CD86) was assessed by flow cytometry. CD3, CD14, CD19, CD56, CD66b-negative, and HLA-DR, CD86 positive are indicative of immature DC. HLA-DR, CD80 and CD83 positive are indicative of mature DC. Results: Mononuclear cells were detected by 27% among allogeneic hematopoietic cell groups harvested by apheresis. After culture under GMP conditions, mononuclear cell rate was found to be 24% on hours 96 and 120. It was seen that 88% of mononuclear cells transformed to mature dendritic cells after 96 hours culture. Conclusion: In cancer patients, minimal residual disease can be eliminated by active tumor vaccine after reducing tumor burden by standard methods. Tumor vaccine obtained from allogeneic sibling donor can be used in lieu of autologous tumor vaccine and it is thought to be more effective. Allogeneic dendritic cells produced at 37°C in CO2 media under GMP conditions can be used in tumor immunotherapy. More effective method would have been used by employing dendritic cells against cancer stem cells rather than cancer cells itself.

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