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L Mascaretti

Publications and source records attributed to L Mascaretti.

At least 19 recordsLinked to original sources

Distribution of killer cell immunoglobulin-like receptors genes in the Italian Caucasian population.

BACKGROUND: Killer cell immunoglobulin-like receptors (KIRs) are a family of inhibitory and activatory receptors that are expressed by most natural killer (NK) cells. The KIR gene family is polymorphic: genomic diversity is achieved through differences in gene content and allelic polymorphism. The number of KIR loci has been reported to vary among individuals, resulting in different KIR haplotypes. In this study we report the genotypic structure of KIRs in 217 unrelated healthy Italian individuals from 22 immunogenetics laboratories, located in the northern, central and southern regions of Italy. METHODS: Two hundred and seventeen DNA samples were studied by a low resolution PCR-SSP kit designed to identify all KIR genes. RESULTS: All 17 KIR genes were observed in the population with different frequencies than other Caucasian and non-Caucasian populations; framework genes KIR3DL3, KIR3DP1, KIR2DL4 and KIR3DL2 were present in all individuals. Sixty-five different profiles were found in this Italian population study. Haplotype A remains the most prevalent and genotype 1, with a frequency of 28.5%, is the most commonly observed in the Italian population. CONCLUSION: The Italian Caucasian population shows polymorphism of the KIR gene family like other Caucasian and non-Caucasian populations. Although 64 genotypes have been observed, genotype 1 remains the most frequent as already observed in other populations. Such knowledge of the KIR gene distribution in populations is very useful in the study of associations with diseases and in selection of donors for haploidentical bone marrow transplantation.

Journal Article↗

Comparative analysis of national regulations concerning blood safety across Europe.

In October 2001, representatives of 17 European countries (Albania, Bosnia-Herzegovina, Bulgaria, Croatia, Czech Republic, Federal Republic of Yugoslavia, Finland, France, Germany, Greece, Italy, Macedonia, Romania, Slovenia, Spain, Turkey and UK) met in Sarajevo at a course organized by the European School of Transfusion Medicine to discuss their countries' regulations concerning different aspects of the safety of blood transfusion. Results are summarized in tables to facilitate comparisons. Most countries (13/17) have specific transfusion laws and 9/17 have hospital-based systems as opposed to national organizations. Quality assurance is common among investigated countries (14/17). Voluntary associations are responsible for donor promotion in the majority of countries (13/17). Exclusively, voluntary non-remunerated donors are found in 5/17 countries, whereas in the remaining ones, incentives, family replacement and remuneration are mechanisms stimulating blood donation. Medical doctors using official selection criteria are checking donor suitability in virtually all countries, which also perform main microbiological testing. Regulations on good clinical use of blood and derivatives are present in most countries but applied only in some. Although the data presented need to be interpreted with some caution, this preliminary analysis shows that, although some significant differences still exist, the majority of countries studied are moving in the same direction to ensure safety of their blood supply.

Blood Banks↗

An immunogenetic map of Lombardy (Northern Italy).

For this study we consulted the Bone Marrow Donors' Registry of Lombardy (Italy) and analyzed 43937 HLA-A,B phenotypes and 13922 HLA-A,B,DR phenotypes. We estimated the HLA-A,B and HLA-A,B,DR haplotype frequencies via the maximum-likelihood method. We analyzed the genetic structure of the 11 provinces of Lombardy by means of Principal Component Analysis and Correspondence Analysis, and estimated the variety of the different haplotypes at provincial level and the percentage of unique phenotypes at village level. We found 11189 different HLA-A,B phenotypes, 661 different HLA-A,B haplotypes and more than 4000 different HLA-A,B,DR haplotypes. We identified 20 villages, in Western Lombardy, very rich in unique/rare phenotypes. Here we report a formula which allows the identification of a putative donor matched for two haplotypes with a recipient. This result may be of great importance for the genetic study of the population of Lombardy and, even more, for bone marrow transplantation programs.

Alleles↗

Comparison of plateletpheresis concentrates produced with Spectra LRS version 5.1 and LRS Turbo version 7.0 cell separators.

BACKGROUND: The importance of transfusing WBC-reduced blood components is widely recognized, as it reduces the risk of alloimmunization and transfusion-transmitted CMV infections. The latest generation of cell separators allows the collection of WBC-reduced apheresis platelet concentrates (APCs). MATERIALS AND METHODS: Consecutive APCs (n = 232) were retrospectively evaluated: 163 collected with the Spectra LRS [leukocyte-reduction system] Version 5.1 (Group A) and 69 with the LRS Turbo Version 7.0 (Group B) (both: COBE BCT). Donor peripheral blood count, procedure data, platelet yield, collection efficiency (CE), and residual WBC count in APCs were recorded. RESULTS: The platelet yield was higher in Group B than in Group A: 5.5 +/- 1.4 versus 4.4 +/- 1.1, p<0.0001; residual WBCs were <5 x 10(6) in 99.4 percent of Group A APCs and in 97.1 percent of Group B APCs. CE was higher in Group B than in Group A: 51.4 +/- 8.7 versus 43.6 +/- 6.3, p<0.0001. Moreover, a correlation between predonation platelet count and platelet yield was observed in both groups. A double product (platelet yield >6.0 x 10(11)) was obtained in 28.9 percent of Group B APCs and in 9.2 percent of Group A APCs. CONCLUSIONS: The Spectra LRS Turbo version 7.0 release showed a better CE and resulted in a higher platelet harvest than did the LRS version 5.1. High predonation platelet counts allow a higher platelet yield.

Blood Cell Count↗

HLA-DRB1 compatibility in cadaver kidney transplantation: correlation with graft survival and function.

The introduction of genomic HLA-DR typing has stimulated a re-evaluation of the role of HLA-DR compatibility on cadaver kidney transplantation. We retrospectively studied the influence of HLA-DRB1 matching on the survival of 416 patients using univariate and Cox regression analysis as well as its influence on the occurrence of rejection episodes and on creatinine level at the 3rd month in the 198 recipients for whom these data were available. The following parameters were also considered: HLA-A,B compatibility, donor and recipient age, graft number, pre-transplant blood transfusions and panel reactive antibodies (PRA). Twenty-four month graft survival was 100% for transplants with zero mismatches (n = 47), 87.9% for those with one mismatch (n = 191) and 81.3% for those with two mismatches (n = 178). In the Cox model, HLA-DRB1 matching was the most significant variable influencing graft survival (47% of chi 2 P = 0.001), followed by HLA-A,B matching (23%, P = 0.02) and donor age (19%, P = 0.04). Ninety-two percent of the patients with zero mismatches experienced no rejection episodes in the first 3 posttransplant months compared with 62% and 41% of patients with one and two mismatches, respectively. Mean creatinine level (mg/dl) was 1.2, 1.4, and 1.5 in patients with zero, one, and two mismatches, respectively. Should these results be confirmed by prospective studies, HLA-DRB1 compatibility will have to be considered as an organ allocation criterion.

Adolescent↗

Cadaver kidney transplantation in the north Italy transplant program in the nineties.

The most relevant changes which have taken place in the NITp in the nineties include the introduction of HLA-DRB1 matching, the extension of both recipient and donor selection criteria, and an increase in donor procurement and consequently, in transplantation activity. Some of the changes in policy resulted from extensive analysis of our previous experience. For the future years, the NITp has set the following priorities: Consolidate the increase of donor procurement activity registered in the past 15 months by educational campaigns for health workers and the public, and organizational measures aimed at strengthening ICUs, nominating transplant coordinators and introducing a system of reimbursement for organs procured. Improve the quality of results in terms of patient rehabilitation and cost-benefit through: continued evaluation of protocols for patient admission on the waiting lists and careful selection of donors; and prospective use of genomic HLA Class II matching and also consider genomic typing for HLA Class I which is almost a reality. Establish a single pool of patients on the waiting list evaluated according to common protocols with the possibility of performing the transplant in each of the authorized centers in turn, respecting the best HLA match and the local use of organs. Finally, standards for donor treatment, organ procurement, histocompatibility testing and transplantation must be established. For this purpose, accreditation programs which have begun to be applied in Europe seem to be the adequate tool.

Adolescent↗

Genomic HLA-DR compatibility in long-term surviving recipients of cadaver kidney transplants.

The finding that HLA-DR compatibility assessed by DNA typing correlates with short-term graft outcome better than serology prompted us to study the degree of genomic HLA-DR compatibility on 55 patients with a graft functioning for more than 10 years (group A), compared with 82 patients with more recent transplants regardless of survival (group B). Because adequate blood donor samples were not available for group A long-term survivors, we used donor renal cells obtained by fine needle aspiration biopsy as a source of DNA. We found that in long-term survivors, the distribution of HLA-DR mismatches was significantly different from that observed in group B patients. In particular, whereas a similar proportion of patients with 1 mismatch was seen in both groups, 27.3% of group A patients vs. 6.1% of group B patients had no mismatch, and 23.6% of group A vs. 41.5% of group B patients received transplants with no HLA-DR compatibility (P = 0.001). We also investigated a possible correlation between number of incompatibilities and graft function. Well-matched patients received less steroid pulses than less well-matched recipients, and steroid-resistant rejection episodes were more common among less well-matched recipients. These results suggest a prognostic role of genomic HLA-DR compatibility on long-term success of cadaver kidney transplantation.

Adult↗

A randomized prospective trial comparing cyclosporine monotherapy with triple-drug therapy in renal transplantation.

In a prospective trial 151 recipients of renal transplants were randomly assigned to treatment with CsA alone (74 patients) and to low dose of AZA, prednisolone, and CsA (77 patients). At two years, graft survival was 84% for the monotherapy and 90% for the triple therapy. This difference was not statistically significant. The number of rejection episodes was similar in the two groups, but the severity of rejection was significantly worse among the patients on monotherapy. More kidneys were lost because of rejection (6 versus 3), and a higher number of methylprednisolone pulses was used for treating rejection (5.2 +/- 2.3 versus 4.3 +/- 2.9; P = 0.0077). CsA nephrotoxicity episodes were more frequent among patients on monotherapy (23 versus 7; P less than 0.02). Infectious episodes were equally distributed between the two groups. Creatinine clearance was poorer in the monotherapy-treated patients at the third month (42 +/- 16 ml/min versus 48 +/- 15 ml/min; P = 0.02), but no differences were observed between the two groups since the sixth month after transplantation. Many patients on monotherapy required changes in maintenance therapy. In fact, one patient was switched to conventional immunosuppression because of Cremophor-induced anaphylaxis. Another patient who developed Kaposi's sarcoma 4 months after surgery was switched to steroids alone. Excluding 5 patients who lost their grafts a few days after transplantation, only 30 of 74 patients (40%) could be kept without steroids. We conclude that both the therapeutic protocols can give good results in renal allotransplantation; however, monotherapy could create some problems in keeping the balance between drug toxicity and significant immunosuppression. On the contrary, triple therapy is easier to handle, especially in the early posttransplant period when the differential diagnosis between acute rejection and CsA-related nephrotoxicity can be difficult even for a skilled clinician.

Adult↗