A novel Leu153Ser mutation of the Fanconi anemia FANCD2 gene is associated with severe chemotherapy toxicity in a pediatric T-cell acute lymphoblastic leukemia.

Fanconi anemia (FA) is an autosomal recessive disease characterized by pancitopenia, congenital malformations, predisposition to cancers and chromosomal instability. We report the clinical and molecular features of a patient initially identified as a potential FA case only because of chemotherapy toxicity during the treatment of a T-lineage acute lymphoblastic leukemia (ALL). Cells from this patient showed a moderate chromosomal instability, increasing sensitivity to DNA crosslinking agents but normal response to ionizing radiation. The analysis of FA proteins demonstrated a marked reduction of FANCD2 (>95%), but normal levels of FANCA or FANCG. Interestingly, this defect was associated with a homozygous missense mutation of FANCD2, resulting in a novel amino-acid substitution (Leu153Ser) at residue Leu153, which is highly conserved through evolution. The FANCD2(L153S) protein, whose reduced expression was not due to impaired transcription, was detected also in its monoubiquitinated form in the nucleus, suggesting that the mutation does not affect post-translation modifications or subcellular localization but rather the stability of FANCD2. Therefore, the hypomorphic Leu153Ser mutation represents the first example of a FANCD2 defect that might promote clonal progression of tumors, such as T-ALL, and severe chemotherapy toxicity in patients without any clinical manifestations typical of FA.

De novo pure 12q22q24.33 duplication: first report of a case with mental retardation, ADHD, and Dandy-Walker malformation.

We present a patient with a de novo 12q nonmosaic pure duplication characterized by multiple minor anomalies and Dandy-Walker malformation. A neurological and behavioral assessment revealed psychomotor retardation and attention deficit/hyperactivity disorder (ADHD), with neurobehavioral abnormalities (auto- and heteroaggressive behavior). Fluoxetine therapy in this case markedly improved the neurobehavioral profile, with a decreased level of aggression. To define the extension of the duplicated region, we performed FISH analyses by using YAC probes. The analyses revealed a tandem duplication of the 12q22q24.33 region, with the proximal breakpoint located between 96.5 and 97.6 cM and the distal one between 154 and 161 cM. This is the first case of pure de novo duplication involving the 12q22q24.33 region. To better define the clinical phenotype associated with 12q partial duplication, we compared our case with the four patients with similar pure duplications previously described.

TCR Vß repertoire in an Italian longeval population including centenarians.

During the last years, the hypothesis that aging and diseases are two distinct phenomena, and that successful aging is possible for most humans, has been put forward. We studied the TCR Vß repertoire of T lymphocytes of healthy longevals and centenarians as crossing point of genetic predisposition and environmental effects to longevity, using the Spectra-typing method. TCR Vß1, Vß8, and Vß20 were found to be expanded in the longeval population, compared with the younger control population. This repertoire can have been shaped by the selective action of particular HLA alleles, or by the clonal expansion of specific T cell clones, able to modulate the immune response to endogenous and exogenous antigens. Moreover, the skewed Vß usage and the clonal expansion seem to be the effects of physiological changes occurring with aging and not pathological signs of malignity.

Chromosome 6p-encoded HLA-DR2 determination discriminates migraine without aura from migraine with aura.

Segregation analysis indicates that migraine without aura (MWoA) and migraine with aura (MWA) have multifactorial inheritance, but involved genetic and environmental factors are largely unknown. A controlled study was performed to assess the HLA-driven liability to migraine and to verify if the heterogeneity between MWoA and MWA is HLA-linked. Forty-five migraine patients (31 MWoA, 14 MWA) and 53 healthy blood donors as controls, coming from the same geographic area, were studied. Tissue typing was performed using the standard complement-dependent microlymphocytotoxicity technique for HLA Class I and by PCR-SSP (Sequences Specific Primers) typing for HLA Class II. Data emerging from the present study showed no altered distribution for HLA Class I A, B, C antigen frequency in migraine (MWoA, MWA) if compared to the control group. HLA Class II DR2 antigen showed a decreased frequency in MWA group if compared with both MWoA (p = 0.01) and control group (p = 0.039, RR = 0.21). These results seem to support the hypothesis of a protective role of DR2 antigen in MWA and provide additional basis for the proposed difference within MWoA and MWA.

HLA-DR and -DQ alleles in Italian patients with melanoma.

Controversial data have been reported about HLA alleles and susceptibility to melanoma. Our investigation was undertaken to analyze the relationship between HLA alleles distribution in patients with melanoma and susceptibility to the tumor, in order to study the possible correlation between HLA class II DQA1, DQB1 and DRB1 genes involved in immune recognition, and melanoma, usually considered a highly immunogenic tumor. We therefore typed by means of PCR-SSP (sequence-specific primers) 53 Italian patients and 53 healthy random controls coming from the same geographic area. We observed a decrease of all haplotypes bearing DQB1*0301, DQB1*0302 and DQB1*0303 alleles but not of haplotype DRB1*11;DQA1*0501;DQB1*0301. Our results seem to support the hypothesis of a protective role of some DQ3-bearing haplotypic combinations in melanoma.

Psoriatic arthritis: a clinical, radiological and genetic study of 58 Italian patients.

It is well known that genetic heterogeneity and/or the complex interaction of several MCH-linked risk factors can explain the onset and the broad spectrum of Psoriatic Arthritis (PsA) from the clinical point of view. Fifty-eight patients with PsA (Moll and Wright criteria), 35 men and 23 women, mean age of 45, 14, were studied; all the patients were assessed by both clinical and radiological examination, with particular attention to the sacroiliac joints. HLA typing of the patients confirmed the association between PsA and HLA-B39 (p = 0.0008) and Cw6 (p = 0.0011). In addition a significant increase in DQ2 antigen (p = 0.004) has been found. No correlation of any particular HLA antigen with clinical subsets (oligo-polyarticular peripheral PsA, axial PsA and axial with peripheral PsA) or erosive incidence of joint involvement-generally related to the duration of the disease--was found.

HLA-linked spinocerebellar ataxia: a clinical and genetic study of large Italian kindreds.

Five families with late onset autosomal dominant spinocerebellar ataxia, were studied. Linkage between the disease and HLA loci on the short arm of chromosome 6 was shown in the two largest pedigrees. Clinical study of 26 patients and neuropathological study in one are reported. The disease was characterized by cerebellar and pyramidal involvement variably associated with cranial nerve and peripheral nervous system disorders. A remarkable concordance of the main clinical features was observed in patients with similar disease duration. Comparison with previous reports of HLA-linked spinocerebellar ataxia kindreds showed differences in clinical phenotypes. Although these might be due to genetic variation, the hypothesis is suggested that the phenotype might appear more homogeneous if disease duration is taken into account.

HLA determinants in familial multiple sclerosis.

HLA-A, -B, -C, -DR, -DQ antigens were studied in 11 multiplex MS families, 11 single-case MS families and 100 healthy subjects. The HLA DR4 was the most frequent antigen in all MS patients (p = 0.015). When the antigenic frequency in index familial cases was compared with that in single cases, the DR4 antigen was found to be more frequent (p = 0.01) in familial cases only. Furthermore, when the DR4 antigen was excluded from the analysis, we observed an increase in DR2 (p = 0.11) only in the familial MS cases. These results can be compatible with a multifactorial hypothesis according to which the HLA genes have an important role in MS susceptibility in familial cases.

HLA-DR and DQ antigens and anticardiolipin antibodies in women with recurrent spontaneous abortions.

IgG anticardiolipin antibodies (ACL) have been shown to occur in a high proportion of women with repeated unexplained miscarriages. Forty-nine women with unexplained recurrent spontaneous abortions (RSA), previously assayed for the presence of ACL by an enzyme-linked immunoabsorbent assay, were typed for HLA-DR and DQ antigens by the classical microlymphocytotoxicity test. Twenty-five women were positive for ACL and 24 were negative. HLA-DR7 was found in 24.5% of 49 habitually aborting women vs. 28% of healthy controls; but the DR7 frequency was 40% in ACL positive patients vs. 8.3% in ACL negative patients (P = 0.011). These results show that in the Italian population an association between HLA-DR7 antigen and ACL is present in women with unexplained RSA, suggesting that HLA-DR genes might control the susceptibility to specific autoantibody production.

HLA antigens and antigliadin antibodies in coeliac disease.

Thirty-six coeliac children on gluten-containing diet were studied for AGA IgA and IgG levels. Patients were typed for HLA-A, -B, -C, -DR, -DQ antigens and data were analysed for any correlation between HLA-DR phenotype and AGA levels. AGA IgA and/or IgG were present in all these children. Subjects negative for DR3 or DR7 showed lower AGA levels than those DR3 + and/or DR7 positive. The data suggest that these patients could escape diagnosis if screening for those requiring intestinal biopsy is based only on AGA assay. The observation that coeliac children negative for DR3 and DR7 showed lower AGA levels is consistent with clinical and genetic heterogeneity of coeliac disease.

HLA antigens in Italian patients with systemic lupus erythematosus: evidence for the association of DQw2 with the autoantibody response to extractable nuclear antigens.

In order to verify the hypothesis that Italian patients with systemic lupus erythematosus (SLE) may be immunogenetically distinct from SLE patients born in other regions, we investigated the HLA class I and II antigens and their relation with the various autoantibodies characteristic of the disease in an Italian SLE population. Forty-four SLE patients were typed for HLA-A, -B, -C, -DR and -DQ antigens; sera from the same patients were tested for the presence of antibodies to the nuclear or cytoplasmic antigens Ro/SSA, La/SSB, Sm and RNP (ENA). Results of HLA typing showed that the frequencies of DR3 and DQw2 were increased in patients compared with controls. Analysis of the correlations between HLA antigens and anti-ENA antibodies showed that both DQw2 and DR3 were increased in patients with anti-Ro and/or antiLa antibodies, while in patients with anti-Sm and/or antiRNP antibodies the DQw2 and DR4 were found to be increased. Only DQw2 was found to be significantly increased in anti-ENA positive patients. These results might suggest that Italian patients with SLE are, at least in part, different from lupus patients living in other geographical areas and suggest the association of DQw2 with the autoantibody response to ENA in SLE.

Spinocerebellar ataxia (SCA1) in two large Italian kindreds: evidence in favour of a locus position distal to GLO1 and the HLA cluster.

Two large Italian pedigrees with HLA-linked spinocerebellar ataxia (SCA1) were typed for HLA-A, -B and -DR as well as for markers either distal (F13A, D6S8) or proximal (D6S29, GLO1) to HLA. Pairwise linkage analyses of SCA1 vs. HLA-A, -B, and -DR showed peak lodscores of 5.3, 5.6 and 3.3 respectively at 7% recombination. Negative lodscores significantly excluded linkage with F13A at less than 5% and with GLO1 at less than 10%. The lodscores with D6S8 and D6S29 had only low peaks. Recombination events in the two pedigrees and the estimated genetic distances of SCA1 from GLO1 and HLA favour the hypothesis of a SCA1 location distal to both of them. An order cen-GLO1-HLA-SCA1-tel appears therefore most likely with present data. These results are discussed in relation to previous reports placing SCA1 distal to HLA in two families and

Humoral and cellular immunological factors as possible markers of clinical relapse in HLA-typed Graves' patients followed with time.

Humoral and cellular immune factors were studied in 33 newly diagnosed Graves' patients at diagnosis and in 12 of these patients at regular intervals thereafter. All the patients were treated with carbimazole for 15 months (initially 60 mg and then 20 mg supplemented with L-Thyroxine). The incidence of relapse after treatment was 42%. Thyrotropin receptor antibodies (TRAb), T-cell subsets, K and NK cells and mononuclear cells expressing surface antigen markers of different activation were evaluated respectively by the use of a radioimmunoassay and a panel of monoclonal antibodies. Patients in the follow-up study were HLA-A, B, C and D typed. TRAb levels (91%) and levels of 4F2-positive cells (73%) and class II-positive lymphocytes (69.6%) were significantly increased in newly diagnosed Graves' patients in comparison with normal controls, whereas CD8 cells were significantly decreased. There was a significant inverse correlation between the increase in 4F2-positive cells and TRAb values. In the follow-up study both humoral and cellular immunological parameters showed a wide variation in levels, but TRAb, 4F2 and L243 values declined on average with respect to diagnosis. After 15 months some patients still showed abnormal values of activated T cells and TRAb values. All patients who relapsed (42%) after medical treatment showed a significant increase of 4F2-positive cells, and some of TRAb, some time before the appearance of clinical symptoms. Finally, no correlation was found between HLA type and relapse of the disease.(ABSTRACT TRUNCATED AT 250 WORDS)

A study of HLA class II antigens in an Italian paediatric population with coeliac disease.

One hundred and twenty-one Italian children with coeliac disease (CD) have been compared with a control population from the same geographical area for the distribution of HLA-DR and DQ antigens. The pattern of an increase in DR3, DR7, and of heterozygotes DR5/7 was associated with an excess of heterozygotes DQw2/DQw3 in the CD population. These findings suggest that epitopes determined by specific combinations of DQ alpha and beta chains (combinatorial determinants) predispose to the disease.

HLA antigens, epilepsy and cytomegalovirus infection.

Thirty-one epileptic patients, selected from among 900 children with previous febrile convulsions and subsequent epilepsy, were typed for HLA antigens. In 16 of the 31 patients CMV was isolated from the urine shortly after the appearance of spontaneous fits; in the remaining 15 patients the virus was never detected. All the examined children were typed for 14 HLA-A, 23 HLA-B, 7 HLA-C and 9 HLA-DR specificities, and compared with a group of healthy subjects. The HLA-A11 antigen was present in 25% of the children with chronic CMV infection and epilepsy, and absent in patients with epilepsy but without CMV infection (p less than 0.02). The possibility that the A11 antigen is a marker of the predisposing genes for CMV infection in children with epilepsy following FC is proposed.

HLA antigens and adult rheumatoid arthritis: a study with a monoclonal antibody.

Adult rheumatoid arthritis (RA) is a very heterogeneous disease that is associated with HLA-antigens, although no absolute association has been found with any particular HLA type. Forty-one seropositive RA patients have been studied with a local monoclonal antibody named X1 21.4 (9w940), strongly associated with HLA-DRI, DR4, Drw10 antigens, to verify a possible correlation with the disease. The results obtained have also been compared with the data reported on MC1, a serologically defined determinant correlated with RA. X1 21.4 monoclonal antibody appears to be associated with the disease and it could identify one epitope involved in the susceptibility to RA.

A mouse monoclonal antibody against a polymorphic determinant in a defined subset of DR molecules.

The hybridoma technique was used to produce a mouse monoclonal antibody, designated as XI 21.4, which belongs to the IgG2a class. It is active in complement-dependent cytotoxicity and detects a B-cell antigenic determinant associated with DR1, DR4, DRw10, and, possibly, DRw9. Microfingerprinting of the immunoprecipitate from a homozygous DR4 cell line shows a typical alpha DR pattern and a beta pattern coinciding with that of DR4 molecules.

[HLA and hypo-responsivity to anti-HBV vaccination (genetic study of non-responder subjects to anti-hepatitis B viral vaccine)]. / HLA e iporesponsività alla vaccinazione anti-HBV (studio genetico di soggetti non-responders al vaccino anti-epatite virale B).

The control of the immunization due to hepatitis B vaccines (HB-VAX and HEVAC B) showed that a low percentage of healthy adults vaccinated develop a non protective title of HBsAb or do not produce antibodies. The correlation between immunity and HLA has already been demonstrated: HLA is at the base of individual immunological response; this correlation directed our genetic study of low-responders or non-responders patients to anti-HBV vaccine. In our study 11 out of 97 subjects vaccinated (11.34%) with HB VAX or HEVAC B resulted hyporesponsive and underwent complete HLA typing to verify the relation between immune deficiency response and genetic system. There was an increase in phenotype HLA-DR7 incidence, with respect to a non-selective population and a decrease of HLA-DR1, as it has already been mentioned in the literature, the variations were not statistically significant taking into account the exiguity of the samples considered.