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- HFE mutations in patients with hereditary haemochromatosis in SwedenPublication . Cardoso, E.; Stal, P.; Hagen, K.; Cabeda, J.; Esin, S.; Sousa, M.; Hultcrantz, R.OBJECTIVE: To determine the frequency of mutations (C282Y and H63D) in a newly identified gene HFE in patients with hereditary haemochromatosis (HH) in Sweden. DESIGN: Molecular genetic analyses of the HFE gene (polymerase chain reaction (PCR) followed by enzyme restriction) were performed in genomic DNA from unrelated patients with a clinical diagnosis of HH and in healthy subjects. SETTINGS: Patients with HH treated with phlebotomies at Karolinska Hospital and Huddinge Hospital were analyzed. SUBJECTS: Eighty-seven unrelated patients with HH and 117 healthy controls. RESULTS: It was found that the HFE C282Y mutation occurs in 94.2% of chromosomes from patients with HH. Eighty patients (92.0%) were homozygous for the C282Y mutation and one was heterozygous. Three patients were heterozygous for both C282Y and H63D mutations. One patient was homozygous and one was heterozygous for the H63D mutation. One patient carried normal alleles. In healthy controls, the C282Y mutation occurred in nine subjects (7.7%), all of which were heterozygous. The H63D mutation was found in 28 control subjects, one of which was homozygous. CONCLUSIONS: We found that the majority of patients with HH have the C282Y mutation in the HFE gene. The frequency of the H63D mutation was higher in controls than in patients with HH, although in chromosomes at risk the frequency of the H63D mutation was higher in patients.
- Major histocompatibility complex class I associations in iron overload: evidence for a new link between the HFE H63D mutation, HLA‐A29, and non‐classical forms of hemochromatosis.Publication . PORTO, G.; ALVES, H.; RODRIGUES, P.; CABEDA, J.M.; PORTAL, C.; RUIVO, A.; JUSTICA, B.; WOLFF, R.; DE SOUSA, M.Immunogenetics. 1998 Apr;47(5):404-10. Major histocompatibility complex class I associations in iron overload: evidence for a new link between the HFE H63D mutation, HLA-A29, and non-classical forms of hemochromatosis. Porto G, Alves H, Rodrigues P, Cabeda JM, Portal C, Ruivo A, Justiça B, Wolff R, De Sousa M. Santo António General Hospital, Largo do Prof. Abel Salazar, no.1, P-4050 Porto, Portugal. Abstract The present study is an analysis of the frequencies of HFE mutations in patients with different forms of iron overload compared with the frequencies found in healthy subjects from the same region. The frequencies of HLA-A and -B antigens and HLA haplotypes were also analyzed in the same subjects. The study population included: 71 healthy individuals; 39 genetically and clinically well-characterized patients with genetic hemochromatosis (HH); and 25 patients with non-classical forms of iron overload (NCH), excluding secondary hemochromatosis. All subjects were HLA-typed and HFE-genotyped by the oligonucleotide ligation assay (OLA). The gene frequencies found for the C282Y and H63D mutations of HFE were respectively: 0.03 and 0.23 in healthy individuals, 0.86 and 0.04 in HH patients, and 0.08 and 0.48 in NCH patients. An expected significant association between HH and HLA-A3 was observed, which was found to be in linkage disequilibrium with the C282Y mutation. A new association was seen, however, between HLA-A29 and NCH, in linkage disequilibrium with the H63D mutation. Again as expected, the HLA-B antigen B7 was associated with HH in linkage disequilibrium with HLA-A3. In addition, the HLA-B antigen B44 was found to be associated with NCH but not in linkage disequilibrium with either A29 or the H63D mutation. In conclusion, a new association of the HFE H63D mutation with forms of hemochromatosis other than HH and a new association between the HLA phenotype A29 and the HFE H63D mutation were found in the same patients. These findings reinforce evidence for the involvement of the major histocompatibility class I in iron metabolism, supporting the notion of a physiological role for the immunological system in the regulation of iron load. PMID: 9510559 [PubMed - indexed for MEDLINE]
- Prevalence of the C282Y and H63D mutations in the HFE gene in patients with hereditary haemochromatosis and in control subjects from Northern GermanyPublication . NIELSEN, P.; CARPINTEIRO, S.; FISCHER, R.; CABEDA, J.M.; PORTO, G.; GABBE, E.E.Br J Haematol. 1998 Dec;103(3):842-5. Prevalence of the C282Y and H63D mutations in the HFE gene in patients with hereditary haemochromatosis and in control subjects from Northern Germany. Nielsen P, Carpinteiro S, Fischer R, Cabeda JM, Porto G, Gabbe EE. Abteilung für Medizinische Biochemie, Universitätskrankenhaus Eppendorf, Hamburg, Germany. Abstract Mutation analysis was performed for two HFE mutations (C282Y, H63D) in unrelated patients with hereditary haemochromatosis (n = 92), family members of patients (n = 34), and unrelated controls (n = 157) from Northern Germany, 87/92 patients (94.6%) revealed the C282Y mutation in homozygous form, five were heterozygous. No H63D mutation was found in 174 chromosomes of patients homozygous for C282Y, whereas four of the heterozygote patients also carried the H63D mutation. Among the control group, 9.6% were heterozygotes for C282Y. 2/157 subjects were homozygous, 37/157 were heterozygous for the H63D mutation, but showed no signs of iron overload. PMID: 9858243 [PubMed - indexed for MEDLINE]
- Unexpected pattern of beta-globin mutations in beta-thalassaemia patients from northern PortugalPublication . Cabeda, J.; Correia, C.; Estevinho, A.; Simões, C.; Amorim, M.; Pinho, L.; Justiça, B.We characterized the genetic nature of beta-thalassaemia in northern Portugal. Of the 164 patients studied three were beta-thalassaemia major cases (one IVS-1-6/beta degrees 39 and two homozygous IVS-1-110). The analysis of the frequency of each mutation in the families revealed that the codon 6(-A) mutation was unexpectedly frequent (40%) and associated with the beta-globin haplotype E, and not with the usual European and North African CD6(-A) haplotypes. In contrast, the frequency of IVS-1-6 (8%) and beta degrees 39 (19%) was found to be lower than in the rest of the country. The frequency of all other mutations was similar to previous reports for central/southern Portugal. Six families carried none of the most frequent mutations in the Mediterranean area. These families were studied by gene sequencing, revealing that three families carried a previously described mutation (CD16 G --> A). The remaining families carried previously unidentified mutations: one showed an 86 bp insertion in exon 2 (named HGSA) and two showed a deletion of a cytidine in codon 11 (CD11(-C)). The results, showing a high frequency (82%) of beta degrees mutations, strongly indicates that genetic counselling should be intensified as a means of preventing the spread of the severe mutations found.
- T cell numbers relate to bone involvement in Gaucher diseasePublication . LACERDA, L.; AROSA, F.A.; LACERDA, R.; CABEDA, J.; PORTO, G.; AMARAL, O.; Fortuna, A.; PINTO, R.; OLIVEIRA, P.; MCLAREN, C.E.; SA MIRANDA, C.; DE SOUSA, M.Blood Cells Mol Dis. 1999 Apr;25(2):130-8. T cell numbers relate to bone involvement in Gaucher disease. Lacerda L, Arosa FA, Lacerda R, Cabeda J, Porto G, Amaral O, Fortuna A, Pinto R, Oliveira P, McLaren CE, Sá Miranda C, de Sousa M. Department of Genetics Neurobiology, Porto University, Portugal. Abstract The major elements of bone pathology in Gaucher disease are a failure of osteoclast and osteoblast function, resulting in osteopenia and also osteonecrosis. T lymphocytes have recently been found to be involved in the regulation of osteoblast/osteoclast activity in vitro. In the present report the peripheral blood T major lymphocyte subsets were investigated in a group of genotyped type 1 Gaucher disease patients. A total of 31 patients were studied: 21 non-splenectomized (5 N370S homozygotes) and 10 splenectomized (of whom 1 was a N370S homozygote). The results show that non-splenectomized patients present a decrease in absolute numbers of peripheral blood T lymphocytes, specially the CD4+ T subset. However, when patients were analyzed with respect to the presence of bone disease, the number of CD8+ T lymphocytes was found to be statistically significantly lower in patients presenting bone involvement. Furthermore, lower numbers of CD8+ T lymphocytes were significantly correlated with higher levels of plasma tartrate resistant acid phosphatase (TRAP) activity, a putative marker of osteoclast cell activity. These in vivo findings are in agreement with the results reached in vitro by others. They provide an additional marker of disease severity in Gaucher disease. In the group of genotyped Gaucher disease patients, the majority of the N370S homozygous patients presented a clinically milder phenotype, including the absence of bone involvement, confirming earlier reports predicting that a number of these patients may remain undiagnosed. Collectively the homozygosity for the N370S mutation and normal T cell numbers may provide additional markers for the clinical heterogeneity of Gaucher disease. PMID: 10389595 [PubMed - indexed for MEDLINE
- Immunophenotypic aberrations, DNA content, and cell cycle analysis of plasma cells in patients with myeloma and monoclonal gammopathiesPublication . LIMA, M.; TEIXEIRA MDOS, A.; FONSECA, S.; GONCALVES, C.; GUERRA, M.; QUEIROS, M.L.; SANTOS, A.H.; COUTINHO, A.; PINHO, L.; MARQUES, L.; CUNHA, M.; RIBEIRO, P.; XAVIER, L.; VIEIRA, H.; PINTO, P.; JUSTICA, B.Blood Cells Mol Dis. 2000 Dec;26(6):634-45. Immunophenotypic aberrations, DNA content, and cell cycle analysis of plasma cells in patients with myeloma and monoclonal gammopathies. Lima M, Teixeira Mdos A, Fonseca S, Gonçalves C, Guerra M, Queirós ML, Santos AH, Coutinho A, Pinho L, Marques L, Cunha M, Ribeiro P, Xavier L, Vieira H, Pinto P, Justiça B. Service of Clinical Hematology, Hospital Geral de Santo António, Rua D Manual II, s/n, 4050 Porto, Portugal. m.lima@ip.pt Abstract We describe the immunophenotypic and gross DNA defects in 55 patients with myeloma and 50 patients with monoclonal gammopathy and review the literature on this subject (MedLine, 1994-2000). Our data confirmed previous reports indicating that in myeloma nearly all marrow plasma cells are abnormal (98.7 +/- 8.1%). In monoclonal gammopathy the fraction of abnormal plasma cells was 35.0 +/- 32.8%. In both myeloma and monoclonal gammopathy, the most frequent aberrant phenotypic features consisted of absence of expression of CD19, strong expression of CD56, and decreased intensity of expression of CD38; aberrant expression of CD10, CD20, CD22, or CD28 was observed in less than one-third of myeloma cases. The vast majority of cases had two or more phenotypic aberrations. In the DNA studies, 7% of myeloma cases were biclonal and 93% of cases were monoclonal. In those studies with only one plasma cell mitotic cycle, 37% had normal DNA content and 63% were aneuploid (hyperploid, 61%; hypoploid, 2%). The mean percentages of plasma cells in S- and G2M phases were 4.9 +/- 8.5 and 4.4 +/- 6.9%, respectively. Thirty-eight percent of cases had more than 3% of plasma cells in S phase. In monoclonal gammopathy, the DNA index of abnormal plasma cells ranged from 0.89 to 1.30 and the percentage of diploid (31%) and aneuploid (69%) cases was not different from the results found in myeloma. The differences in percentage of abnormal plasma cells in S- (7.4 +/- 8.6%) and G2M-phases (2.4 +/- 1.7%) in patients with monoclonal gammopathy were not statistically significant. Copyright 2000 Academic Press. PMID: 11358356 [PubMed - indexed for MEDLINE]
- An unusual acute myeloid leukemia associated with hyper IgE: another case of AML‐M5c?Publication . LIMA, M.; ORFAO, A.; COUTINHO, J.; FERREIRA, G.; FREITAS, I.; SILVESTRE, F; JUSTICA, B.Haematologica. 2001 Feb;86(2):216-7. An unusual acute myeloid leukemia associated with hyper IgE: another case of AML-M5c? Lima M, Orfão A, Coutinho J, Ferreira G, Freitas I, Silvestre F, Justiça B. PMID: 11224498 [PubMed - indexed for MEDLINE]
- Immunophenotypic characterization of normal blood CD56+lo versus CD56+hi NK‐cell subsets and its impact on the understanding of their tissue distribution and functional propertiesPublication . LIMA, M.; TEIXEIRA, M.A.; QUEIROS, M.L.; LEITE, M.; SANTOS, A.H.; JUSTICA, B.; ORFAO, A.Blood Cells Mol Dis. 2001 Jul-Aug;27(4):731-43. Immunophenotypic characterization of normal blood CD56+lo versus CD56+hi NK-cell subsets and its impact on the understanding of their tissue distribution and functional properties. Lima M, Teixeira MA, Queirós ML, Leite M, Santos AH, Justiça B, Orfão A. Service of Clinical Hematology, Unit of Cytometry, Hospital Geral de Santo António, Porto, Portugal. mmc.lima@clix.pt Abstract In the present study we have compared the immunophenotypic characteristics of the CD56+lo and CD56+hi NK-cell subsets in a group of normal healthy adults. Our results show that CD56+hi NK-cells display greater light-scatter properties than CD56+lo NK-cells at the same time they have higher levels of CD25 and CD122 IL-2 chains, together with a higher reactivity for HLA-DR and CD45RO and lower levels of CD45RA, supporting that, as opposed to the majority of the CD56+lo population, CD56+hi NK-cells might correspond to a subset of activated circulating NK-lymphocytes. Higher expression of the CD2 and CD7 costimulatory molecules found for the CD56+hi NK-cells would support their greater ability to respond to various stimuli. In addition, CD56+hi NK-cells expressed higher levels of several adhesion molecules such as CD2, CD11c, CD44, CD56, and CD62L compared to CD56+lo NK-cells, supporting a particular ability of these cells to migrate from blood to tissues and/or a potential advantage to form conjugates with target cells. Interestingly, CD56+lo and CD56+hi NK-cells showed a different pattern of expression of killer receptors that might determine different activation requirements for each of these NK-cell subsets. For instance, absence or low levels of CD16 expression might explain the lower antibody-dependent cytotoxicity activity of CD56+hi NK-cells. On the other hand, the virtual absence of expression of the CD158a and NKB1 immunoglobulin-like and the greater reactivity for the CD94 lectin-like killer receptors on CD56+hi in comparison to CD56+lo NK-cells might determine different MHC-class I specificities for both NK-cell subsets, a possibility that deserves further studies to be confirmed. PMID: 11778657 [PubMed - indexed for MEDLINE]
- Clinical and genetic heterogeneity in hereditary haemochromatosis: association between lymphocyte counts and expression of iron overloadPublication . Porto, Graça; CARDOSO, C.S.; GORDEUK, V.; CRUZ, E.; FRAGA, J.; AREIAS, J.; OLIVEIRA, J.C.; BRAVO, F.; GANGAIDZO, I.T.; MACPHAIL, A.P.; GOMO, Z.A.; MOYO, V.M.; MELO, G.; SILVA, C.; JUSTICA, B.; DE SOUSA, M.Eur J Haematol. 2001 Aug;67(2):110-8. Clinical and genetic heterogeneity in hereditary haemochromatosis: association between lymphocyte counts and expression of iron overload. Porto G, Cardoso CS, Gordeuk V, Cruz E, Fraga J, Areias J, Oliveira JC, Bravo F, Gangaidzo IT, MacPhail AP, Gomo ZA, Moyo VM, Melo G, Silva C, Justiça B, de Sousa M. Haematology, Santo António General Hospital, Porto, Portugal. gporto@ibmc.up.pt Abstract To identify a new marker of expression of disease, independent of HFE genotype in patients with hereditary haemochromatosis (HHC), the total peripheral blood lymphocyte counts were analysed according to iron status in two groups of subjects with HFE mutations. The groups consisted of 38 homozygotes for C282Y, and 107 heterozygotes for the C282Y or compound heterozygotes for C282Y and H63D. For control purposes, total lymphocyte counts and iron status were also examined in 20 index patients with African dietary iron overload, a condition not associated with HFE mutations, and in 144 members of their families and communities. Mean lymphocyte numbers were lower in C282Y homozygous HHC index subjects with cirrhosis and higher iron stores than in those without cirrhosis and with lower iron burdens [(1.65 +/- 0.43) x 10(6)/mL vs. (2.27 +/- 0.49) x 10(6)/mL; p = 0.008]. Similarly, mean lymphocyte counts were significantly lower in C282Y heterozygotes and C282Y/H63D compound heterozygotes with iron overload and increased serum ferritin concentrations compared to those with normal serum ferritin concentrations (p < 0.05). Statistically significant negative correlations were found, in males, between lymphocyte counts and the total body iron stores, either in C282Y homozygous HHC patients (p = 0.031 in a multiple regression model dependent on age) and in C282Y heterozygotes or C282Y/H63D compound heterozygotes with iron overload (p = 0.029 in a simple linear model). In contrast, lymphocyte counts increased with increasing serum ferritin concentrations among the index subjects with African iron overload (r = 0.324, not statistically significant) and among the members of their families and communities (r = 0.170, p = 0.042). These results suggest that a lower peripheral blood lymphocyte count is associated with a greater degree of iron loading in HFE haemochromatosis but not in African iron overload, and they support the notion that the lymphocyte count may serve as a marker of a non-HFE gene that influences the clinical expression of HFE haemochromatosis.
- Immunophenotypic analysis of the TCR‐Vbeta repertoire in 98 persistent expansions of CD3(+)/TCR‐alphabeta(+) large granular lymphocytes: utility in assessing clonality and insights into the pathogenesis of the diseasePublication . LIMA, M.; ALMEIDA, J.; SANTOS, A.H.; DOS ANJOS TEIXEIRA, M.; ALGUERO, M.C.; QUEIROS, M.L.; BALANZATEGUI, A.; JUSTICA, B.; GONZALEZ, M.; SAN MIGUEL, J.F.; ORFAO, A.Am J Pathol. 2001 Nov;159(5):1861-8. Immunophenotypic analysis of the TCR-Vbeta repertoire in 98 persistent expansions of CD3(+)/TCR-alphabeta(+) large granular lymphocytes: utility in assessing clonality and insights into the pathogenesis of the disease. Lima M, Almeida J, Santos AH, dos Anjos Teixeira M, Alguero MC, Queirós ML, Balanzategui A, Justiça B, Gonzalez M, San Miguel JF, Orfão A. Serviço de Hematologia Clínica, Unidade de Citometria, Hospital Geral de Santo António, Porto, Portugal. mmc.lima@clix.pt Abstract At present, a major challenge in the initial diagnosis of leukemia of large granular lymphocytes (LGLs) is to establish the clonal nature of the expanded population. In the present study we have analyzed by flow cytometry immunophenotyping the TCR-Vbeta repertoire of 98 consecutive cases of persistent expansions of CD4(+) or CD8(+bright) CD3(+)/TCR-alphabeta(+) LGLs and compared the results with those obtained in molecular studies of TCR-beta gene rearrangements. Fifty-eight cases were considered to be monoclonal in molecular studies whereas in the remaining 40 cases there was no evidence for monoclonality (11 cases were considered oligoclonal and 29 polyclonal). The TCR-Vbeta repertoire was biased to the preferential use of one or more TCR-Vbeta families in 96% of cases, a total of 124 TCR-Vbeta expansions being diagnosed: one TCR-Vbeta expansion in 71 cases and two or more TCR-Vbeta expansions in 23 cases. The highest TCR-Vbeta expansion observed in each case was higher among monoclonal (74 +/- 19%) as compared to nonmonoclonal cases (24 +/- 14%) (P = 0.001), as did the fraction of LGLs that exhibited a TCR-Vbeta-restricted pattern (86 +/- 16% and 42 +/- 23%, respectively; P = 0.0001); by contrast, the proportion of cases displaying more than one TCR-Vbeta expansion was higher in the latter group: 7% versus 48%, respectively (P = 0.001). Results obtained in oligoclonal cases were intermediate between those obtained in polyclonal and monoclonal cases and similar results were observed for CD4(+) as for CD8(+bright) T-cell expansions. TCR-Vbeta families expressed in CD8(+bright) T-cell-LGL proliferations showed a pattern of distribution that mimics the frequency at which the individual TCR-Vbeta families are represented in normal peripheral blood T cells. Assuming that a given proliferation of LGLs is monoclonal whenever there is an expansion of a given TCR-Vbeta family of at least 40% of the total CD4(+) or CD8(+bright) T-cell compartment, we were able to predict clonality with a sensitivity of 93% and a specificity of 80%. By increasing the cut-off value to 60%, sensitivity and specificity were of 81% and 100%. In summary, our results suggest that flow cytometry immunophenotypic analysis of the TCR-Vbeta repertoire is a powerful screening tool for the assessment of T-cell clonality in persistent expansions of TCR-alphabeta(+) LGLs. PMID: 11696446 [PubMed - indexed for MEDLINE]PMCID: PMC1867049