F Falzetti

Prognostic significance of genetic variants in the IL-23/Th17 pathway for the outcome of T cell-depleted allogeneic stem cell transplantation

T helper (Th) 17 cells have emerged as important mediators in infectious and inflammatory diseases and, recently, in transplant rejection. We analyzed the associations between five common genetic variants in the IL-23/Th17 signaling pathway, namely in IL17A, IL17F and IL23R genes, and clinical outcome in T cell-depleted allogeneic SCT (allo-SCT). In the multivariate analysis, variants in IL23R and IL17A genes were the most important prognostic factors. Thus, patient GA genotype at rs11209026 in IL23R was associated with improved overall survival (hazard ratio (HR)=0.48; P=0.028) and, in donor, with decreased risk of fungal infections (P=0.05). In contrast, patient TC and CC genotypes at rs8193036 in IL17A gene were associated with increased risk of CMV infection (HR=3.68; P=0.011) and patient acute GVHD (HR=7.08; P=0.008), respectively. These results suggest that genetic variants in the IL-23/Th17 inflammatory pathway are important prognostic factors for the clinical outcome of allo-SCT. Although validation studies are ultimately required, our results would suggest the potential usefulness of IL-23/Th17 genotyping in donor selection and patient evaluation.

Peripheral blood progenitor cell mobilization in healthy donors receiving recombinant human granulocyte colony-stimulating factor

OBJECTIVE We analyzed the incidence of primitive (LTC-IC) and committed (CFU-mix, BFU-E, CFU-GM) hematopoietic progenitors detected under steady-state conditions and upon progenitor cell mobilization in a cohort of healthy donors receiving recombinant human granulocyte colony-stimulating factor (rhG-CSF). MATERIALS AND METHODS Healthy donors (n = 30) of HLA-mismatched or -matched stem cell transplants were mobilized with rhG-CSF (8 microg/Kg body weight subcutaneously twice daily until completion of leukapheresis). PBPC collections were started after 4 days of rhG-CSF therapy. RESULTS Steady-state incidence of bone marrow LTC-IC, but not committed progenitors, significantly correlated with the numbers of mobilized CD34+ cells (r = 0.6, p = 0.004), CFU-GM (r = 0.79, p = 0.0005) and CFC (r = 0.76, p = 0.001) detected after 4 days of rhG-CSF therapy. Statistically significant correlations were also found between steady-state blood CFU-GM and peak numbers of CD341 cells (r = 0.68, p = 0.001), numbers of day 4 CD341 cells (r = 0.52, p = 0.005), CFU-GM (r = 0.63, p = 0.002), and CFC (r = 0.61, p = 0.003). CONCLUSION Our data show that in normal volunteers baseline marrow LTC-IC and blood CFU-GM correlate with rhG-CSF-mobilized PBPC. The potential clinical relevance of these findings in the identification of poor mobilizers will be tested in a prospective study.

A microelectronic DNA chip detects the V617F JAK-2 mutation in myeloproliferative disorders

A microelectronic DNA chip detects the V617F JAK-2 mutation in myeloproliferative disorders

G-CSF-induced thrombocytopenia in a healthy donor

Recombinant human G-CSF (rhG-CSF) is widely used in haematopoietic stem cell mobilization in allogeneic transplant donors. rhG-CSF administration causes a mean eightfold rise in the WBC count and a slight decrease in haemoglobin. The plt count may fall slightly, possibly because of splenomegaly, which may be enhanced by the apheresis-related procedure. Here, we report a case of thrombocytopenia induced by rhG-CSF administration in a healthy donor with no evidence of splenomegaly before apheresis started. The 51-year-old brother of a man with multiple myeloma was selected as matched donor for transplantation. Medical history included two episodes of Quincke’s oedema, the first at the age of 33 years after cephalosporine administration, and the second at the age of 43 years after nimesulide. Clinical examination, chest X-ray, electrocardiogram, blood chemistry and urine analysis were normal. Serology was negative for hepatitis A, B and C viruses, HIV-1, herpes virus types 1 and 2 and toxoplasma. IgG tests were positive for cytomegalovirus and the Epstein– Barr virus. After providing informed consent, the donor was admitted to hospital for s.c. infusion of rhG-CSF (lenograstim 12 mg/kg body wt per day). WBC and plt counts and haemoglobin level were monitored before starting haematopoietic stem cell mobilization and daily during mobilization and collection (Figure 1). The plt count started to drop on day 1 of rhG-CSF administration, and three blood samples on day 4 provided plt counts of 77 10/l, 69 10/l and 63 10/l, respectively. As this donor was the only one in the patient’s family, and the CD34þ cell count was sufficient, the leukapheresis procedures were performed with a continuous flow blood cell separator (COBE Spectra, Lakewood, CO, USA). The plt count was 37 10/l afterwards. On day 6, the plt count of 78 10/l before leukapheresis had fallen into 30 10/l later. On day 7, as the plt count was 27 10/l, leukapheresis procedures were suspended and the plt count monitored. On days 8 and 9, it was unchanged. On day 10 (72 h after suspending rhG-CSF), it started to rise slightly, reaching 50 10/l whereupon the patient was discharged from hospital. On day 16 (9 days after stopping rhG-CSF), the plt count rebounded to 268 10/l. Pretreatment plt counts were reached on day 37. Screening for autoimmune disease, including detection of anti-plt antibodies, was negative. Three abdominal ultrasound scans showed no splenomegaly. As the CD34þ cell harvest was insufficient to constitute a graft, BM was explanted from the donor. Checkups for 1 year after rhG-CSF administration showed normal blood parameters. During haematopoietic stem cell mobilization in healthy donors, slight thrombocytopenia is common and is attributed to the leukapheresis procedure or to splenomegaly.

Next generation HLA-haploidentical HSCT.

Relapse is still the major cause of failure of allogeneic stem cell transplantation in high-risk acute leukemia patients. Indeed, whoever the donor and whatever the transplantation strategy, post-transplant relapse rates are ~30%, which is hardly satisfactory. The present phase 2 study analyzed the impact of adoptive immunotherapy with naturally occurring FoxP3+ T-regulatory cells (2 × 106 per kg) and conventional T lymphocytes (1 × 106 per kg) on prevention of GvHD and leukemia relapse in 43 high-risk adults undergoing full-haplotype mismatched transplantation without any post-transplant immunosuppression. Ninety-five percent of patients achieved full-donor type engraftment. Only 6/41 patients (15%) developed ⩾grade II acute GvHD. Specific CD4+ and CD8+ for opportunistic pathogens emerged significantly earlier than after standard T-cell-depleted haplo-transplantation. The probability of disease-free survival was 0.56. At a median follow-up of 46 months (range 18–65 months), only 2/41 evaluable patients have relapsed. The cumulative incidence of relapse was significantly lower than in historical controls (0.05 vs 0.21; P=0.03). These results demonstrate that the immunosuppressive potential of Tregs can be used to suppress GvHD without loss of the benefits of GvL activity. Humanized murine models provided insights into the mechanisms underlying separation of GvL from GvHD.

Evolution of multiple cytogenetic clones and leukemic transformation in a case of myelodysplastic syndrome

The cytogenetic follow-up of a case of refractory anemia with excess of blasts (RAEB) that rapidly evolved to acute myeloblastic leukemia (Ml-FAB type) is described. Bone marrow analysis at presentation revealed two chromosomally abnormal clones that shared an interstitial deletion of the long arm of chromosome 5 (5q−) and a terminal deletion of the short arm of chromosome 12 (12p-), but that differed from one another in the localization of a very similar segment of chromosome 17 (i.e. 17q11−12qter) on two clearly distinct karyotypic sites: 2q37 and 17q25. Fourteen percent of the metaphases examined bore the 2q+ marker and 38% the 17q+ marker; the remaining cells had a normal karyotype. A second study carried out 4 months later, at onset of the acute phase, revealed that the clone with normal karyotype had almost completely disappeared and that there had been an inversion in the ratio of the two abnormal cell populations. In the final study, made 1 month before death, the cells with t(2;17) had totally effaced the other clone.These findings seem to indicate that, among the karyotypic changes that occurred in an original clone with 5q− and 12p−, only the t(2;17) could have played a crucial role in the final leukemic transformation.

Erratum: γ-Secretase inhibitor I induces apoptosis in chronic lymphocytic leukemia cells by proteasome inhibition, endoplasmic reticulum stress increase and Notch down-regulation (International Journal of Cancer (2013) 132: 8 (1940-1953) DOI: 10.1002/ijc.27863)

Rosati E, Sabatini R, De Falco F, Del Papa B, Falzetti F, Di Ianni M, Cavalli L, Fettucciari K, Bartoli A, Screpanti I, Marconi P. gSecretase inhibitor I induces apoptosis in chronic lymphocytic leukemia cells by proteasome inhibition, endoplasmic reticulum stress increase and Notch down-regulation. Int J Cancer. 2013 Apr 15;132(8):1940–1953. doi: 10.1002/ijc.27863. Epub 2012 Oct 17. In this article, Figure 1b contained an error in the plot relative to DMSO treatment at 1 hr. The plot image of DMSO was mistakenly the same plot image relative to GSI treatment at 1 hr, but the gating numbers were correct. The corrected Figure 1b, showing the correct DMSO plot image, is now provided. The authors regret this error, which however, does not alter the conclusions of the study.