At the combined American Society for Apheresis (ASFA) Annual Meeting/World Apheresis Association (WAA) Congress in San Francisco, California, in April of 2014, the opening session highlighted the status of apheresis outside of the United States. The organizers invited physicians active in apheresis in countries not usually represented at such international gatherings to give them a forum to share their experiences, challenges, and expectations in their respective countries with regard to both donor and therapeutic apheresis. Apheresis technology is expensive as well as technically and medically demanding, and low and median income countries have different experiences to share with the rest of the world. Apheresis procedures also require resources taken for granted in the developed world, such as reliable electrical power, that can be unpredictable in parts of the developing world. On the other hand, it was obvious that there are significant disparities in access to apheresis within the same country (such as in Brazil), as well as between neighboring nations in Africa and South America. A common trend in the presentations from Brazil, Indonesia, Malaysia, Nigeria, and South Africa, was the need for more and better physicians and practitioners' training in the indications of the various apheresis modalities and patient oversight during the procedures. As ASFA and WAA continue to work together, and globalization allows for increased knowledge-sharing, improved access to apheresis procedures performed by qualified personnel with safety and high-quality standards will be increasingly available.

SummarySeveral investigators have reported that interferon-gamma (IFN³) can alter tumor necrosis factor alpha induced effects in vitro. We assessed in vivo effects of recombinant interferon-gamma (rIFN³) on recombinant tumor necrosis factor-alpha (rTNF±) induced activation of systemic blood coagulation in a non-randomized study in 20 consecutive cancer patients. Eight patients were treated with rIFN³ prior to and during hyperthermic isolated limb perfusion with rTNF± and melphalan (IFN³ group). They were compared with twelve patients who did not additionally receive rIFN³ (non-IFN³ group)Before start of perfusion, higher levels of TNFa, F1+2 and TAT levels were found in the IFN³ group. Fibrinogen and ATIII levels tended to be lower in this group. High TNF± levels, due to leakage during perfusion, were associated with activation of coagulation in all patients, that became obvious after the end of perfusion, when heparin treatment had been antagonized. Activation, measured by increased F1+2 and TAT levels, was significantly stronger in the IFN³y group. Monocytic TF remained low, possibly due to shedding of TF positive vesicles and/or sequestration of TF positive activated monocytes against the vessel wall. In both groups F1+2 and TAT levels declined 24 h after the perfusion, whereas monocytic TF increased to levels that were higher in the IFN³ group.In conclusion, our data confirm a strong activation of coagulation induced by rTNF± in cancer patients. They suggest that rIFN³ may lead to a slight activation of coagulation and augments TNFa induced procoagulant activity. These effects may be due to rIFN³ induced sustained monocytic TF activity.

Platelet storage at 04 C suppresses bacterial multiplication, but induces clusters of glycoprotein (GP) Ibalpha that trigger their phagocytosis by macrophages and reduce their survival after transfusion. We searched for a method that detects cold-induced changes in GPIbalpha involved in phagocytosis. STUDY DESIGN AND METHODS: Human platelets were isolated and stored for up to 48 hrs at 0C. Binding of a PE-labeled antibody directed against amino acids 1–35 on GPIbalpha (AN51-PE) was compared with phagocytosis of platelets by matured monocytic THP-1 cells, analyzed by FACS. RESULTS: Freshly isolated platelets were detected as a single population of AN51-PE positive particles and showed < 5% phagocytosis. Cold storage led to a decrease in AN51-PE binding and an increase in phagocytosis. N-acetylglucosamine (GlcNAc), known to interfere with macrophage recognition of GPIbalpha clusters, restored normal AN51-PE binding to cold-stored platelets and suppressed phagocytosis. CONCLUSIONS: We conclude that binding of an antibody against AA 1–35 on GPIbalpha reflects changes in GPIbalpha that make platelets targets for phagocytosis by macrophages.

4473 Autologous stem cell transplantation (ASCT) is a frequently applied treatment modality for patients with multiple myeloma (MM) and relapsing lymphoma. However, patients treated for relapsing disease post-ASCT demonstrate a reduced tolerance to chemotherapy, even those patients that have shown an adequate engraftment. These observations suggest long-term effects of the transplantation procedure on the bone marrow (BM) capacity. In the present study we analyzed in more detail the hematopoietic stem cell/progenitor defects in de BM of patients post-ASCT. BM cells from patients 6-9 months post-ASCT (n=16 including 5 patients with MM and 11 patients with relapsing lymphoma) were obtained after informed consent. At the moment of investigation patients displayed normal peripheral blood cell counts with a mean Hb level of 7.6 mmol/l, a mean leukocyte count of 6.9 × 109/l, a mean granulocyte count of 4.4 × 109/l and a mean platelet count of 202 × 109/l. CD34+ cells were isolated from the BM material and analyzed by flowcytometry for progenitor subsets. Common myeloid progenitors (CMP) were defined as CD34+CD110-CD45RA-, granulocyte-macrophage progenitors (GMP) as CD34+CD110-CD45RA+ and megakaryocyte-erythroid progenitors (MEP) as CD34+CD110+CD45RA-. A phenotypical shift was observed from CMP (mean percentage 3.7% (95%CI 0.7-6.9) vs. 19.4% (95%CI 11.3-27.6), p=0.001) to GMP (mean percentage 51.8% (95%CI 39.6-64.2) vs. 27.6% (95%CI 19.6-35.5), p=0.01) in patients 6-9 months post-ASCT compared to CD34+ cells from healthy controls (n=7). No distinct difference in progenitor subsets was observed between MM and lymphoma patients. Comparable results were obtained in a limited number of patients at a later time point of follow-up (24 months post-ASCT). To further characterize the CD34+ cell fraction post-ASCT, progenitor frequencies were determined in CFC assays. A significant decrease in CFC frequency per 103 plated CD34+ cells was observed compared to normal CD34+ BM cells (109 ± 52 vs. 185 ± 56, p=0.008). The decrease in CFC frequency from post-ASCT CD34+ cells was not due to an impaired proliferative activity. Cell cycle analysis revealed a significantly higher fraction of CD34+ cells post-ASCT in G2/S phase (mean 29% (95%CI 19.1-38.4) vs. 14% (95%CI 1.6-25.7), p=0.03) and a reduced percentage of cells in G1 phase (mean 67% (95%CI 56.4-78.2) vs. 86% (95%CI 73.9-98.4), p=0.03) compared to normal CD34+ cells. It appeared that especially the GMP fraction of post-ASCT CD34+ cells displayed a higher cycling activity (35% (95%CI 27.7-43.0) in G2/S phase vs. 19% (95%CI 13.0-25.7), p=0.03) whereas no significant differences for the MEP and CMP fractions were observed. The increased in vitro cycling activity could be confirmed in vivo by performing 18F-FLT PET scans in 10 patients post-ASCT. The results indicated a significant increase in standard uptake values (SUV) measured in the BM compartment. The mean SUV of the left and right area were compared to normal controls (n=12) and measured at different locations of the BM compartment including femur (3.6 ± 0.7 vs. 1.2 ± 0.5, p<0.001), crista (3.9 ± 0.6 vs. 2.2 ± 0.5, p<0.001) and spine (4.7 ± 2.5 vs. 3.9 ± 0.7, p<0.005). In addition, a significant expansion of the BM compartment of patients post-ASCT was noticed compared to normal controls. In summary, the results of this study demonstrate that ASCT results in long-term defects of the hematopoietic compartment characterized by a shift in progenitor composition from CMP to GMP, a reduced in vitro colony frequency and a higher in vitro and in vivo cycling activity of CD34+ BM cells of patients 6-9 months post-ASCT. Disclosures: No relevant conflicts of interest to declare.