Allogeneic bone marrow transplantation (BMT) from a genotypically identical family donor is an accepted therapeutic option for homozygous beta-thalassemia. However, only a minority of patients have access to this curative procedure. The aim of this study is to explore the feasibility of matched unrelated transplants in thalassemia and the possibility of reducing the risk of immunologic complications through careful selection of donor/ recipient pairs. Since November 1992, 32 patients (age range, 2-28 years) have been enrolled. There were 4 patients assigned to risk-class I, 11 to risk-class II, and 17 to risk-class III of the Pesaro classification. Extended haplotype analysis and family segregation studies were employed for identification of suitable donors. Of the 32 donor/recipient pairs, 24 were identical for HLA-A, B, C, DRB1, DRB3, DRB4, DRB5, DQA1, and DQB1 loci; 7 pairs were identical for 2 extended haplotypes, and 15 pairs shared one extended haplotype. Grade II-IV acute graft-versus-host disease (GVHD) developed in 11 cases (41%) and chronic GVHD in 6 (25%) out of 24 patients at risk. There are 22 patients (69%) who are alive and transfusionindependent after a median follow-up of 30 months (range, 7-109 months). There were 6 patients (19%) who engrafted and subsequently died from transplant-related complications. In 4 cases (12.5%) graft rejection was observed within 30 days and it was followed by autologous IntroductionAllogeneic bone marrow transplantation (BMT) from a genotypically identical family donor has radically changed the prognosis of patients with homozygous beta-thalassemia. For young patients at an early stage of disease, the reported percentage of thalassemiafree survival and the mortality risk were 91% and 8%, respectively. 1,2 Transplantation performed on older, heavily iron-loaded patients, in particular those with liver abnormalities, has a lesssatisfactory outcome, the probability of thalassemia-free survival and mortality being 51% and 32%, respectively. 3 The probability of finding an HLA-identical donor within the family is less than 30% in western countries. 4 For the remaining 70% of patients with thalassemia, there was until recently no option other than treatment based on chronic transfusion and ironchelating therapy. Although optimization of protocols for transfusion and chelation has dramatically improved the life expectancy of these patients, complications of iron overload cannot be completely avoided. 5,6 Full compliance with a chronic transfusion regimen and a daily, lifelong injective chelation therapy has been shown to be difficult to maintain with advancing age. 7 Multiple endocrine dysfunctions, myocardiopathy, progressive liver fibrosis, and consequences of posttransfusion viral infections affect the quality of life and increase the mortality risk with age. [7][8][9] During the past 10 years, BMT from unrelated donors has been increasingly employed for hematologic malignancies and lifethreatening inborn errors. [10][11][12] At first, results were characterized by el...
HLA class II antigens and DRB1, DQA1, DQB1 alleles were studied in 16 Italian and in 16 Sardinian patients with pemphigus vulgaris (PV). In the last group the complete HLA A-DQ haplotypes, including the complotypes, were defined by family studies. As in other populations, two PV susceptibility haplotypes were found: HLA-DRB1*0402, DQA1*0301, DQB1*0302 and HLA-DRB1*1401, DQA1*0104, DQB1*0503. The first haplotype was largely prevalent in the Sardinian patients and was a part of the extended haplotype HLA-A2, Cw4, B35, S31, DR4, DQ8. The strength of the allele associations to PV is in agreement with the view that the main PV susceptibility genes are the DRB1*0402 and DQB1*0503 alleles. A genetic resistance to PV seems to be conferred by the HLA-DR3, DQ2 haplotype in the Sardinian population.
IntroductionCNS dissemination in patients with aggressive non-Hodgkin lymphoma (NHL) is a relatively rare but often fatal complication that occurs in the different subtypes of NHL with a frequency of 5% (ie, diffuse large B-cell lymphoma [DLBCL]) to 30% 1 (ie, Burkitt lymphoma [BL] and B-cell lymphoblastic lymphoma [B-LL]). Many CNS events occur early after diagnosis (4.7-9 months), during therapy, or shortly after completion of treatment, suggesting that initial CNS involvement could have been undetected in most cases. Prophylactic treatment likely reduces the incidence of CNS relapse, but may increase the toxicity of systemic chemotherapy; furthermore, the incidence of CNS dissemination is not high enough to suggest the use of prophylaxis treatment in all patients affected by aggressive NHL. Therefore, CNS prophylaxis is usually incorporated into protocols for the treatment of B-LL and BL, but it is not systematically warranted in patients with DLBCL. Therefore, the identification of patient subgroups for which CNS prophylaxis may be useful is important, especially for DLBCL patients who have no well-defined risk factors for CNS relapse. Risk models for DLBCL have been developed, but are mainly derived from analyses of retrospective studies. [2][3][4][5] An increased risk of CNS dissemination is associated with involvement of the BM and certain extranodal sites such as testis, paranasal sinuses, orbits, and paravertebral masses. Moreover, patients with a high to intermediate or high risk according to the International Prognostic Index (IPI), particularly those with high serum levels of lactate dehydrogenase (LDH) and involvement of more than 1 extranodal organ, are much more prone to develop CNS involvement than others and should receive CNS prophylaxis. 6 Nevertheless, CNS risk predictors and related prognostic scores have been identified in retrospective and heterogeneous series, including different lymphoma categories; however, resulting scores show a low sensitivity in predicting CNS involvement.The diagnosis of CNS dissemination is frequently suspected by the presence of related signs or symptoms and confirmed by examination of cerebrospinal fluid (CSF) and neuroimaging techniques. The diagnostic standard conventional cytology (CC) examination of CSF is considered as having low sensitivity and low specificity, with reported falsenegative rates of 20%-60%. 7 This has been ascribed to the paucity of neoplastic cells in the CSF of patients with minimal disease and to the presence of confounding reactive lymphocytes. Therefore, patients with low tumor burden in the CSF, who are more likely to benefit from CNS treatment, are actually more commonly exposed to false-negative [8][9][10][11][12][13][14] However, it is still unknown whether detecting occult leptomeningeal involvement and consequently changing treatment may improve outcome in these patients.In the present study, we compared prospectively FCM analysis versus CC examination of baseline samples of CSF to detect occult leptomeningeal disease in patie...
A study on the HLA structure of the Sardinian population was carried out on 551 healthy unrelated families representing all of the island districts. Altogether 2202 HLA-A, B, Cw, DR individual haplotypes and 853 different haplotypes were determined. Cavalli-Sforza and Edwards' genetic distance index for the total of 62 tested alleles showed a modest heterogeneity between one district and another (0.09-0.16). The genetic distance between Sardinians and the rest of the Italian population was 0.23 (0.22-0.26) and progressively increased in comparisons with caucasoids (0.26), negroids (0.34) and mongoloids (0.41). Sixty-three two-locus haplotypes with a high positive linkage disequilibrium were observed in our family sample. The percentages of two-locus haplotypes in LD shared with other populations turned out to be 45% with caucasoids, 20% with negroids and 10% with mongoloids. The distribution of the A, B, Cw, DR haplotypes is shown with 673 of them represented only once or twice, and 10 (1.2%) 14-322 times each. Of the latter, 8 are extended haplotypes, 6 of which characterize the Sardinian population. The analysis of our data suggests that the present-day Sardinian population is the result of a superposition of different populations, mainly consisting of caucasoids on a pre-caucasoid paleo-Mediterranean substratum.
BackgroundKidney transplantation is a life-saving treatment for patients with end-stage renal disease. However, despite progress in surgical techniques and patient management, immunological rejection continues to have a negative impact on graft function and overall survival. Incompatibility between donors and recipients for human leukocyte antigens (HLA) of the major histocompatibility complex (MHC) generates a series of complex cellular and humoral immune response mechanisms that are largely responsible for rejection and loss of graft function. Within this context, a growing amount of evidence shows that alloreactive natural killer (NK) cells play a critical role in the immune response mechanisms elicited by the allograft. Killer immunoglobulin-like receptors (KIRs) are prominent mediators of NK cell alloreactivity.Methods and findingsA cohort of 174 first cadaveric kidney allograft recipients and their donors were selected from a total cohort of 657 transplanted patients for retrospective immunogenetic analyses. Patients with HLA Class II mismatches were excluded. HLA Class I allele frequencies were compared among patients with chronic rejection, patients with stable graft function and a group of 2388 healthy controls. Activating and inhibitory KIR gene frequencies, KIR haplotypes, KIR-HLA ligand matches/mismatches and combinations of recipient KIRs and donor HLA Class I ligands were compared among patients with and without chronic rejection and a group of 221 healthy controls.Patients transplanted from donors homozygous for HLA-C1 antigens had a significantly higher risk for chronic rejection than patients transplanted from donors homozygous or heterozygous for HLA-C2 antigens or with epitopes belonging to the HLA-Bw4 ligand group.The Kaplan-Meier curves obtained by dividing the patients into 3 groups according to the presence or absence of one or both of the combinations of recipient KIRs and donor HLA ligands (rKIR2DL1/dHLA-C2 and rKIR3DL1/dHLA-Bw4) showed a significantly higher cumulative incidence of chronic rejection in the group of patients completely lacking these functional units. These patients showed a progressively stronger decline in modification of diet in renal disease-estimated glomerular filtration rate.ConclusionsKIR genotyping should be performed at the time of enrolment of patients on the waiting list for organ transplantation. In our study, a significantly higher risk of chronic rejection after kidney transplantation was observed when recipient (r) and donor (d) pairs completely lacked the two functional rKIR-dHLA ligand combinations rKIR2DL1/dHLA-C2 and rKIR3DL1/dHLA-Bw4. This immunogenetic profile corresponds to low levels of NK cell inhibition. Therefore, patients with this high risk profile could benefit from immunosuppressive therapy aimed at reducing NK-cell cytotoxicity.
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