The influence of cell concentration at cryopreservation on neutrophil engraftment after autologous peripheral blood stem cell transplantation

ABSTRACT Background: Peripheral blood stem cell concentrations are traditionally adjusted to 20-40 × 106 leukocytes/mL prior to freezing. This low cell concentration at cryopreservation implies larger volumes with more dimethyl sulfoxide being used, and higher cost and toxicity at the time of transplant. Higher cell concentrations have been reported but this is not widely accepted. Moreover, the influence of cell concentration on engraftment has not been well documented. Therefore, this study retrospectively analyzed the influence of peripheral blood stem cell concentration at freezing on engraftment after autologous hematopoietic stem cell transplantation. Method: Leukapheresis products were plasma-depleted and cryopreserved with 5% dimethyl sulfoxide, 6% hydroxyethylamide solution and 4% albumin in a −80 °C freezer. Individual patient data from hospital records were reviewed. Results: Fifty consecutive patients with oncological diseases underwent 88 leukaphereses. Median age was six years (range: 1-32 years) and median weight was 19 kg (range: 8-94 kg). Median leukocyte concentration was 109 × 106/mL at collection and 359 × 106 (range: 58-676 × 106) at freezing with 78% viability (range: 53-95%); leukocyte recovery after thawing was 95% (range: 70-100%). In multivariate analysis, cell concentration (p-value = 0.001) had a negative impact on engraftment. Patients infused with bags frozen with <200 × 106 leukocytes/mL engrafted after a median of nine days (range: 8-12 days), 200-400 × 106 leukocytes/mL after 11 days (range: 9-20 days); 400-600 × 106 leukocytes/mL after 12 days (range: 8-19 days) and with cell concentrations >600 × 106 leukocytes/mL, engraftment was after 14 days (range: 13-22 days). Conclusion: In patients with adequate CD34 cell collections, total leukocyte concentrations of 282 × 106/mL, freezing with 5% dimethyl sulfoxide and 6% hydroxyethylamide solution without a controlled-rate freezer, and storing cells at −80 ºC yielded excellent engraftment. Further increases in cell concentration may delay engraftment, without affecting safety.

The influence of cell concentration at cryopreservation on neutrophil engraftment after autologous peripheral blood stem cell transplantation.

BACKGROUND: Peripheral blood stem cell concentrations are traditionally adjusted to 20-40 × 106 leukocytes/mL prior to freezing. This low cell concentration at cryopreservation implies larger volumes with more dimethyl sulfoxide being used, and higher cost and toxicity at the time of transplant. Higher cell concentrations have been reported but this is not widely accepted. Moreover, the influence of cell concentration on engraftment has not been well documented. Therefore, this study retrospectively analyzed the influence of peripheral blood stem cell concentration at freezing on engraftment after autologous hematopoietic stem cell transplantation. METHOD: Leukapheresis products were plasma-depleted and cryopreserved with 5% dimethyl sulfoxide, 6% hydroxyethylamide solution and 4% albumin in a -80 °C freezer. Individual patient data from hospital records were reviewed. RESULTS: Fifty consecutive patients with oncological diseases underwent 88 leukaphereses. Median age was six years (range: 1-32 years) and median weight was 19 kg (range: 8-94 kg). Median leukocyte concentration was 109 × 106/mL at collection and 359 × 106 (range: 58-676 × 106) at freezing with 78% viability (range: 53-95%); leukocyte recovery after thawing was 95% (range: 70-100%). In multivariate analysis, cell concentration (p-value = 0.001) had a negative impact on engraftment. Patients infused with bags frozen with <200 × 106 leukocytes/mL engrafted after a median of nine days (range: 8-12 days), 200-400 × 106 leukocytes/mL after 11 days (range: 9-20 days); 400-600 × 106 leukocytes/mL after 12 days (range: 8-19 days) and with cell concentrations >600 × 106 leukocytes/mL, engraftment was after 14 days (range: 13-22 days). CONCLUSION: In patients with adequate CD34 cell collections, total leukocyte concentrations of 282 × 106/mL, freezing with 5% dimethyl sulfoxide and 6% hydroxyethylamide solution without a controlled-rate freezer, and storing cells at -80 °C yielded excellent engraftment. Further increases in cell concentration may delay engraftment, without affecting safety.

[Choroidal Melanoma]. / Melanoma da Coroideia.

Choroidal melanoma is the most common primary intraocular malignant tumor in adults. None of the different treatments available offers advantages of survival, resorting more and more to conservative treatments such as brachytherapy, which has been available in Portugal since 2013. In this article we review the clinical characteristics, risk factors, diagnosis, complementary exams and therapeutic options in choroidal melanoma.

O melanoma da coroideia é o tumor primário intraocular maligno mais frequente em adultos. Nenhum dos diferentes tratamentos disponíveis oferece vantagens de sobrevida recorrendo-se, cada vez mais, a tratamentos conservadores como a braquiterapia, a qual passou a estar disponível em Portugal desde 2013. Neste artigo revemos as características clínicas, factores de risco, diagnóstico, exames complementares e opções terapêuticas no melanoma da coroideia.

Effects of X-radiation on lung cancer cells: the interplay between oxidative stress and P53 levels.

Lung cancer (LC) ranks as the most prevalent and deadliest cause of cancer death worldwide. Treatment options include surgery, chemotherapy and/or radiotherapy, depending on LC staging, without specific highlight. The aim was to evaluate the effects of X-radiation in three LC cell lines. H69, A549 and H1299 cell lines were cultured and irradiated with 0.5-60 Gy of X-radiation. Cell survival was evaluated by clonogenic assay. Cell death and the role of reactive oxygen species, mitochondrial membrane potential, BAX, BCL-2 and cell cycle were analyzed by flow cytometry. Total and phosphorylated P53 were assessed by western blotting. Ionizing radiation decreases cell proliferation and viability in a dose-, time- and cell line-dependent manner, inducing cell death preferentially by apoptosis with cell cycle arrest. These results may be related to differences in P53 expression and oxidative stress response. The results obtained indicate that sensibility and/or resistance to radiation may be dependent on molecular LC characteristics which could influence response to radiotherapy and treatment success.