Host defense pathways against fungi: the basis for vaccines and immunotherapy.

Fungal vaccines have long been a goal in the fields of immunology and microbiology to counter the high mortality and morbidity rates owing to fungal diseases, particularly in immunocompromised patients. However, the design of effective vaccination formulations for durable protection to the different fungi has lagged behind due to the important differences among fungi and their biology and our limited understanding of the complex host-pathogen interactions and immune responses. Overcoming these challenges is expected to contribute to improved vaccination strategies aimed at personalized efficacy across distinct target patient populations. This likely requires the integration of multifaceted approaches encompassing advanced immunology, systems biology, immunogenetics, and bioinformatics in the fields of fungal and host biology and their reciprocal interactions

Etiology of febrile episodes in patients with acute myeloid leukemia: results from the Hema e-Chart Registry

Several studies have attempted to analyze the epidemiologic patterns of infectious complications in patients with acute myeloid leukemia (AML), although the power of these studies was frequently limited by their retrospective design.1 - 2 .A lively debate currently focuses on the potential of Internet-based software and associated technologies, such as electronic medical records, to simplify reporting, to improve database content, and to optimize the timing of interventions.3 - 4 Because a well-designed surveillance system is essential for the systematic collection, analysis, and dissemination of data, we designed an electronic medical record system.

Successful lectin-separated bone marrow transplantation in adenosine deaminase deficiency-related severe immunodeficiency

Severe combined immunodeficiency disease (SCID) with adenosine deaminase (ADA) deficiency is a genetic autosomic recessive disorder with profound impairment of T-cell function, invariably complicated by fatal infections. The absence of ADA-enzyme and the accumulation of deoxy-ATP, with toxic effects on the T-lymphocytes is the common feature of this disease. As a consequence, lymphoid precursors failure to develop into mature T-cells, resulting in absolute lymphopenia and atrophy of the thymus. Bone marrow transplantation from an HLA-identical donor is considered the treatment of choice for this disease. We describe the case of a 1-month-old child with ADA deficiency SCID who underwent bone marrow transplantation (BMT) using paternal haploidentical, lectin-separated marrow, as a source of hemopoietic stem cells

Genetically-determined hyperfunction of the S100B/RAGE axis is a risk factor for aspergillosis in stem cell transplant recipients

Invasive aspergillosis (IA) is a major threat to the successful outcome of hematopoietic stem cell transplantation (HSCT), although individual risk varies considerably. Recent evidence has established a pivotal role for a danger sensing mechanism implicating the S100B/receptor for advanced glycation end products (RAGE) axis in antifungal immunity. The association of selected genetic variants in the S100B/RAGE axis with susceptibility to IA was investigated in 223 consecutive patients undergoing HSCT. Furthermore, studies addressing the functional consequences of these variants were performed. Susceptibility to IA was significantly associated with two distinct polymorphisms in RAGE (-374T/A) and S100B (+427C/T) genes, the relative contribution of each depended on their presence in both transplantation counterparts [patient SNP(RAGE), adjusted hazard ratio (HR), 1.97; P = 0.042 and donor SNP(RAGE), HR, 2.03; P = 0.047] or in donors (SNP(S100B), HR, 3.15; P = 7.8e-(4)) only, respectively. Functional assays demonstrated a gain-of-function phenotype of both variants, as shown by the enhanced expression of inflammatory cytokines in RAGE polymorphic cells and increased S100B secretion in vitro and in vivo in the presence of the S100B polymorphism. These findings point to a relevant role of the danger sensing signaling in human antifungal immunity and highlight a possible contribution of a genetically-determined hyperfunction of the S100B/RAGE axis to susceptibility to IA in the HSCT setting

Clinical use of allogeneic hematopoietic stem cells from sources other than bone marrow

Peripheral blood stem cells (PBSC) are being increasingly used as an alternative to conventional allogeneic bone marrow (BM) transplantation. This has prompted the Working Group on CD34-Positive Hematopoietic Cells to evaluate the current utilization of allogeneic PBSC in clinical hematology. The method employed for preparing this review was that of informal consensus development. Members of the Working Group met three times, and the participants at these meetings examined a list of problems previously prepared by the chairman. They discussed the single points in order to reach an agreement on different opinions and eventually approved the final manuscript. Some of the authors of the present review have been working in the field of stem cell transplantation and have contributed original papers in peer-reviewed journals. In addition, the material examined in the present review includes articles and abstracts published in journals covered by the Science Citation Index and Medline. Review of the current literature shows that unmanipulated allogeneic PBSC give prompt and stable engraftment in HLA-identical sibling recipients. Despite the much higher number of T-cells infused, the incidence and severity of acute GVHD after PBSC transplant seems comparable to that observed with bone marrow (BM) cells. In comparison to the latter, PBSC probably ensure faster immunologic reconstitution in the early post-transplant period. Controversial results on the incidence and severity of acute-GVHD have been reported when CD34+ selection methods are used. Prospective randomized trials are underway to compare the results of PBSC and BM allogeneic transplantation. In mismatched family donor transplants, T-cell depleted PBSC successfully engraft immune-myeloablated recipients through a megacell-dose effect able to overcome the HLA barrier. Experience with PBSC in the context of unrelated donor transplants is currently anecdotal and prospective trials should be completed before that practice becomes routine. Finally, there is also limited evidence that, following induction chemotherapy, the addition of PBSC to donor lymphocyte infusion (DLI) for treatment of leukemia relapse after BMT may improve the safety and effectiveness of DLI itself. Concerning cord blood (CB) transplants, the most interesting aspects are the ease of CB collection and storage, the low risk of viral contamination and the low immune reactivity of CB cells. This last property has its clinical counterpart in an apparently reduced incidence and severity of acute GVHD both in sibling and unrelated CB transplants, probably making the level of donor/recipient HLA disparity acceptable a greater degree with respect to what is required for transplants from other sources

Immunoselection and clinical use of T regulatory cells in HLA-haploidentical stem cell transplantation

INTRODUCTION: Haploidentical transplantation, with extensive T cell depletion to prevent GvHD, is associated with a high incidence of infection-related deaths. The key challenge is to improve immune recovery with allogeneic donor T cells without triggering GvHD. As T regulatory cells (Tregs) controlled GvHD in pre-clinical studies, the present study evaluated the impact of an infusion of donor CD4/CD25 + Tregs, followed by an inoculum of donor mature T cells (Tcons) and positively immunoselected CD34 + cells in the setting of haploidentical stem cell transplantation. PATIENTS AND METHODS: Twenty-eight patients were enrolled in this study (22 AML; 5 ALL; 1 NHL). All received immunoselected Tregs (CliniMACS, Miltenyi Biotec) followed by positively immunoselected CD34 + cells together with Tcons 4 days later. No GvHD prophylaxis was administered. RESULTS: 26/28 patients engrafted. No acute GvHD developed in 24/26 patients; 2 developed ≥ grade II acute GvHD. No patient has developed chronic GvHD. CD4 and CD8 counts rapidly increased after transplant. Episodes of CMV reactivation were significantly fewer than in controls. CONCLUSIONS: In the setting of haploidentical transplantation infusion of Tregs makes administration of a high dose of T cells feasible. This strategy provides a long-term protection from GvHD and robust immune reconstitution

Results and factors influencing outcome after fully haploidentical hematopoietic stem cell transplantation in children with very high-risk acute lymphoblastic leukemia: impact of center size: an analysis on behalf of the Acute Leukemia and Pediatric Disease Working Parties of the European Blood and Marrow Transplant group.

T cell-depleted haploidentical hematopoietic stem cell transplantation (haploHSCT) is an option to treat children with very high-risk acute lymphoblastic leukemia (ALL) lacking an HLA-identical donor. We analyzed 127 children with ALL who underwent haploHSCT in first (n = 22), second (n = 48), or third (n = 32), complete remission or in relapse (n = 25). The 5-year leukemia-free survival (LFS) was 30%, 34%, 22%, and 0%, respectively. A risk-factor analysis was performed for patients who underwent transplantation in remission (n = 102). Five-year nonrelapse mortality (NRM), relapse incidence (RI), and LFS were 37%, 36%, and 27%, respectively. A trend of improved LFS rate and decreased RI was observed for children given a graft with higher number of CD34(+) cells (adjusted P = .09 and P = .07, respectively). In a multivariate analysis, haploHSCT performed in larger centers (performing > or = 231 allotransplantations in the studied period) was associated with improved LFS rate and decreased RI (adjusted P = .01 and P = .04, respectively), adjusting for different patient-, disease-, and transplant-related factors such as number of previous autotransplantations, cytomegalovirus serology status, type of T-cell depletion, and use of total body irradiation and antithymocyte globulin. In conclusion, higher CD34(+) cell dose and better patient selection may improve outcomes of children with ALL who undergo a haploHSCT. Transplant centers initiating programs on haploHSCT for children may collaborate with more experienced centers

Unrelated donor marrow transplantation for chronic myelogenous leukemia

Between January 1989 and July 1995 the search for an unrelated donor (UD) was started for 379 consecutive Italian patients with Philadelphia positive (Ph+) chronic myelogenous leukaemia (CML). 89 (23%) were transplanted. The overall probability of transplant before and after December 1991 was 16% and 49%, respectively (P=0.0001), and average interval between search activation and graft was 23 months and 13 months, respectively (P=0.0001). Disease-free survival (DFS) following 60 consecutive transplants performed before February 1996 was 41.5% at 48 months and was 64% for patients grafted after January 1993. In univariate analysis, five variables had a favourable effect on DFS: year of bone marrow transplantation (BMT) after 1993 (P=0.0002), HLA-DRB1 donor/recipient (D/R) match (P=0.0006), total body irradiation (TBI) containing regimen (P=0.0006), graft-versus-host disease (GvHD) prophylaxis including 'early' cyclosporin before the transplant, and a marrow cell dose > 3 x 10(8)/kg of recipient body weight (P=0.04). Multivariate analysis confirmed that HLA identity (P=0.006), TBI-containing regimen (P=0.0001) and 'early cyclosporin' (P=0.04) were associated with higher DFS. Transplant-related mortality (TRM) was 67% in patients grafted before January 1993 and 30% in patients grafted subsequently (P=0.002). Multivariate analysis confirmed DRB1 identity (P=0.03) and TBI-containing regimen (P=0.0005) to be independent factors predictive of low TRM. This suggests that the outcome of patients transplanted from an HLA DRB1 matched donor, after a TBI-containing preparative regimen, is similar to results recently reported in patients transplanted from geno-identical siblings. These results indicate that the search should be initiated at diagnosis for patients < 45 years of age and UD BMT should be considered early in the disease course for those with an available DRB1-matched unrelated donor