Resolution of HLA-B*44:02:01G, -DRB1*14:01:01G and -DQB1*03:01:01G reveals a high allelic variability among 12 European populations.

Within the framework of the EU-funded HLA-NET action, an analysis of three G-group alleles, HLA-B*44:02:01G, DRB1*14:01:01G and DQB1*03:01:01G, was undertaken in 12 European populations. Ambiguities were resolved by polymerase chain reaction-sequence-specific amplification (PCR-SSP) or PCR-sequence-based typing (PCR-SBT) in a total of 5095 individuals. The results of the DRB1*14:01/14:54 ambiguity showed high relative ratios (24-53%) of DRB1*14:01 in Bulgarians, Croatians, Greeks, Italians and Slovenians, contrasting with low ratios (6-13%) in Austrians, Finnish, French, Hungarians, Norwegians and Swiss. Resolution of the B*44:02/44:27 ambiguity showed that B*44:27 had a high relative ratio in Slovenians (25.5%) and Bulgarians (37%) and low in French and Swiss (0.02-1%), and was not observed in Greeks and Italians. The highest relative ratio of DQB1*03:19 was found in Portuguese (11%), by contrast with low ratios (0-3%) in the other five populations. Analysis of the A, B, DRB1 phenotypes and family-derived haplotypes in 1719 and 403 individuals positive for either HLA-B*44:02G or DRB1*14:01G ambiguities, respectively, showed some preferential associations, such as A*26∼DRB1*14:01, B*35∼DRB1*14:01, B*38∼DRB1*14:01 and B*44:27∼DRB1*16. Because these ambiguities are located outside the peptide-binding site, they may not be recognized by alloreactive T-cells. However, because of strong linkage disequilibrium (LD), the DRB1*14:01 vs DRB1*14:54 and the B*44:02 vs B*44:27 mismatches are associated to DRB3-, and C-mismatches, respectively. These results are informative for algorithms searching unrelated hematopoietic stem cell donors. For B*44:27-positive patients, searches are expected to be more successful when requesting donors from Southeastern-European ancestry. Furthermore, the introduction of human leukocyte antigen (HLA)-typing strategies that allow resolving exon 4 (for class I) and exon 3 (for class II) polymorphisms can be expected to contribute significantly to population genetics studies.

16(th) IHIW: analysis of HLA population data, with updated results for 1996 to 2012 workshop data (AHPD project report).

We present here the results of the Analysis of HLA Population Data (AHPD) project of the 16th International HLA and Immunogenetics Workshop (16IHIW) held in Liverpool in May-June 2012. Thanks to the collaboration of 25 laboratories from 18 different countries, HLA genotypic data for 59 new population samples (either well-defined populations or donor registry samples) were gathered and 55 were analysed statistically following HLA-NET recommendations. The new data included, among others, large sets of well-defined populations from north-east Europe and West Asia, as well as many donor registry data from European countries. The Gene[rate] computer tools were combined to create a Gene[rate] computer pipeline to automatically (i) estimate allele frequencies by an expectation-maximization algorithm accommodating ambiguities, (ii) estimate heterozygosity, (iii) test for Hardy-Weinberg equilibrium (HWE), (iv) test for selective neutrality, (v) generate frequency graphs and summary statistics for each sample at each locus and (vi) plot multidimensional scaling (MDS) analyses comparing the new samples with previous IHIW data. Intrapopulation analyses show that HWE is rarely rejected, while neutrality tests often indicate a significant excess of heterozygotes compared with neutral expectations. The comparison of the 16IHIW AHPD data with data collected during previous workshops (12th-15th) shows that geography is an excellent predictor of HLA genetic differentiations for HLA-A, -B and -DRB1 loci but not for HLA-DQ, whose patterns are probably more influenced by natural selection. In Europe, HLA genetic variation clearly follows a north to south-east axis despite a low level of differentiation between European, North African and West Asian populations. Pacific populations are genetically close to Austronesian-speaking South-East Asian and Taiwanese populations, in agreement with current theories on the peopling of Oceania. Thanks to this project, HLA genetic variation is more clearly defined worldwide and better interpreted in relation to human peopling history and HLA molecular evolution.

Strategies to work with HLA data in human populations for histocompatibility, clinical transplantation, epidemiology and population genetics: HLA-NET methodological recommendations.

HLA-NET (a European COST Action) aims at networking researchers working in bone marrow transplantation, epidemiology and population genetics to improve the molecular characterization of the HLA genetic diversity of human populations, with an expected strong impact on both public health and fundamental research. Such improvements involve finding consensual strategies to characterize human populations and samples and report HLA molecular typings and ambiguities; proposing user-friendly access to databases and computer tools and defining minimal requirements related to ethical aspects. The overall outcome is the provision of population genetic characterizations and comparisons in a standard way by all interested laboratories. This article reports the recommendations of four working groups (WG1-4) of the HLA-NET network at the mid-term of its activities. WG1 (Population definitions and sampling strategies for population genetics' analyses) recommends avoiding outdated racial classifications and population names (e.g. 'Caucasian') and using instead geographic and/or cultural (e.g. linguistic) criteria to describe human populations (e.g. 'pan-European'). A standard 'HLA-NET POPULATION DATA QUESTIONNAIRE' has been finalized and is available for the whole HLA community. WG2 (HLA typing standards for population genetics analyses) recommends retaining maximal information when reporting HLA typing results. Rather than using the National Marrow Donor Program coding system, all ambiguities should be provided by listing all allele pairs required to explain each genotype, according to the formats proposed in 'HLA-NET GUIDELINES FOR REPORTING HLA TYPINGS'. The group also suggests taking into account a preliminary list of alleles defined by polymorphisms outside the peptide-binding sites that may affect population genetic statistics because of significant frequencies. WG3 (Bioinformatic strategies for HLA population data storage and analysis) recommends the use of programs capable of dealing with ambiguous data, such as the 'gene[rate]' computer tools to estimate frequencies, test for Hardy-Weinberg equilibrium and selective neutrality on data containing any number and kind of ambiguities. WG4 (Ethical issues) proposes to adopt thorough general principles for any HLA population study to ensure that it conforms to (inter)national legislation or recommendations/guidelines. All HLA-NET guidelines and tools are available through its website http://hla-net.eu.

Analysis of the HLA population data (AHPD) submitted to the 15th International Histocompatibility/Immunogenetics Workshop by using the Gene[rate] computer tools accommodating ambiguous data (AHPD project report).

During the 15th International Histocompatibility and Immunogenetics Workshop (IHIWS), 14 human leukocyte antigen (HLA) laboratories participated in the Analysis of HLA Population Data (AHPD) project where 18 new population samples were analyzed statistically and compared with data available from previous workshops. To that aim, an original methodology was developed and used (i) to estimate frequencies by taking into account ambiguous genotypic data, (ii) to test for Hardy-Weinberg equilibrium (HWE) by using a nested likelihood ratio test involving a parameter accounting for HWE deviations, (iii) to test for selective neutrality by using a resampling algorithm, and (iv) to provide explicit graphical representations including allele frequencies and basic statistics for each series of data. A total of 66 data series (1-7 loci per population) were analyzed with this standard approach. Frequency estimates were compliant with HWE in all but one population of mixed stem cell donors. Neutrality testing confirmed the observation of heterozygote excess at all HLA loci, although a significant deviation was established in only a few cases. Population comparisons showed that HLA genetic patterns were mostly shaped by geographic and/or linguistic differentiations in Africa and Europe, but not in America where both genetic drift in isolated populations and gene flow in admixed populations led to a more complex genetic structure. Overall, a fruitful collaboration between HLA typing laboratories and population geneticists allowed finding useful solutions to the problem of estimating gene frequencies and testing basic population diversity statistics on highly complex HLA data (high numbers of alleles and ambiguities), with promising applications in either anthropological, epidemiological, or transplantation studies.

Visfatin, TNF-alpha and IL-6 mRNA expression is increased in mononuclear cells from type 2 diabetic women.

Visfatin, is a new adipokine, highly expressed in the visceral fat of both mice and humans. To examine whether visfatin is expressed in human peripheral monocyte-enriched mononuclear cells and whether its expression is altered in type 2 diabetes (DM2), we compared 24 DM2 women [17 overweight (BMI >25) and 7 lean (BMI<25)] to 26 healthy women (14 overweight and 12 lean), all premenopausal. Relative visfatin mRNA levels were significantly higher (approximately 3-fold) in DM2 compared to healthy control women (p<0.02), independently of the presence of overweight/obesity. Mononuclear TNF-alpha and IL-6 mRNA expression was also elevated in DM2 compared to control women (p=0.001 and p=0.004, respectively), an increase observed in both lean and overweight DM2 women. By contrast, circulating visfatin, TNF-alpha, and IL-6 levels showed no difference between DM2 and control women, while adiponectin plasma levels were significantly decreased in the DM2 women (p<0.001). Circulating visfatin and TNF-alpha levels did not differ either between the lean and the overweight subgroups of DM2 and control women, while IL-6 plasma levels were significantly higher in both overweight subgroups compared to their lean counterparts. In conclusion, visfatin, TNF-alpha, and IL-6 mRNA expressions are increased in peripheral mononuclear-monocytic cells from women with type 2 diabetes, independent of their BMI, which may enhance the effects of their adipose-derived levels and may contribute to the increased insulin resistance and atherogenic risk of these patients.

Opposed independent effects and epistasis in the complex association of IRF5 to SLE.

Genetic variation in the interferon regulatory factor 5 (IRF5) gene affects systemic lupus erythematosus (SLE) susceptibility. However, association is complex and incompletely defined. We obtained fourteen European sample collections with a total of 1383 SLE patients and 1614 controls to better define the role of the different IRF5 variants. Eleven polymorphisms were studied, including nine tag single nucleotide polymorphisms (SNPs) and two extra functional polymorphisms. Two tag SNPs showed independent and opposed associations: susceptibility (rs10488631, P<10(-17)) and protection (rs729302, P<10(-6)). Haplotype analyses showed that the susceptibility haplotype, identified by the minor allele of rs10488631, can be due to epistasis between three IRF5 functional polymorphisms. These polymorphisms determine increased mRNA expression, a splice variant with a different exon 1 and a longer proline-rich region in exon 6. This result is striking as none of the three polymorphisms had an independent effect on their own. Protection was independent of these polymorphisms and seemed to reside in the 5' side of the gene. In conclusion, our results help to understand the role of the IRF5 locus in SLE susceptibility by clearly separating protection from susceptibility as caused by independent polymorphisms. In addition, we have found evidence for epistasis between known functional polymorphisms for the susceptibility effect.

Bias in association studies of systemic lupus erythematosus susceptibility due to geographical variation in the frequency of a programmed cell death 1 polymorphism across Europe.

We obtained eight collections of DNA samples from ethnically matched systemic lupus erythematosus (SLE) patients and controls from five European countries totaling 783 patients and 1210 controls. A highly significant cline in the frequency of the PD1.3 A allele was found among controls but not among SLE patients. The frequency of the PD1.3 A allele increased from the Northeast to the Southwest of Europe. The cline was clearly apparent (P=1.2 x 10(-6)) when data from controls of other five SLE susceptibility studies were included in the analysis. This variation has severely biased SLE association studies owing to the lack of parallel changes in SLE patients. As a consequence, the PD1.3 A allele was more common in SLE patients than in controls in the Northeast and Center of Europe, similar to controls in Southeast Europe, and less frequent than in the controls in the Southwest of the Continent. This dissociation in allele frequencies between SLE patients and controls in different subpopulations indicated that programmed cell death 1 variation and disease susceptibility are not independent but the type of relationship is currently unclear. As allele frequency clines are common in other polymorphisms their impact in genetic epidemiology studies should be carefully considered.

HLA antigens as predictors of disease progression in HIV-infected haemophilia patients (a 22 years' follow up).

Our objective was to assess the influence of genetic factors such as HLA classes I and II antigens and other clinical and laboratory variables on the progression of HIV disease in a cohort of 118 HIV infected haemophilic subjects of Greek origin who had been typed for HLA antigens and were followed up prospectively for 22 years since seroconversion. At the end of the follow up we compared two groups of patients: 22 patients who had a fast progression to AIDS (median 6 years since seroconversion) vs. 33 patients who remained asymptomatic in stage A2 for up to 22 years (median 15 years). The results showed that the two groups did not differ significantly in age at seroconversion or baseline CD4+ T cell count. However there was a difference in the frequencies of certain HLA antigens in the two groups. The fast progressors had a higher frequency of HLA-A28, B21 and DR3, which was statistically significant (P = 0.02, 0.04, 0.05, respectively) compared to the slow progressors. These findings based on classical HLA typing techniques confirm other published observations and support the effect of genetic background in the progression of HIV infection in haemophilics.

HLA-G in murine peripheral blood after interruption of pregnancy.

HLA-G antigens are highly expressed in maternal peripheral blood during early pregnancy in transgenic mice. In this study, we determined the levels of HLA-G in white blood cells during early pregnancy and after interruption of pregnancy in triple transgenic mice (H-2K(b)/HLA-G, hbeta2m, and hCD2/hCD8-TRI). The pregnancies were interrupted on day 7 using the anti-progesterone agent mifepristone (RU486). Blood samples of 20 pregnant TRI mice were taken and the HLA-G levels were determined on days 2, 4 and 6 of pregnancy and on days 9, 11 and 13 after fertilization. The monoclonal antibody W6/32, specific for monomorphic determinant HLA class I molecules, was used in combination with an immunolocalization method using a photonic microscope. The HLA-G levels increased gradually on days 2, 4 and 6 of pregnancy, and the interruption of pregnancy on day 7 was followed by a decrease of HLA-G levels. The data indicate that pregnancy is characterized by the early presence of HLA-G in maternal peripheral blood in TRI transgenic mice and suggest that HLA-G may serve as a useful indicator for pregnancy maintenance and well-being.

Thyroid hormone excess increases basal and insulin-stimulated recruitment of GLUT3 glucose transporters on cell surface.

BACKGROUND: In hyperthyroidism, tissue glucose disposal is increased to adapt to high energy demand. Our aim was to examine the glucose transporter isoforms involved in this process and their regulation through insulin in monocytes from subjects with hyperthyroidism. METHODS: Blood (20 ml) was withdrawn from 12 healthy and 12 hyperthyroid subjects. The abundance of glucose transporter isoforms (GLUT) on the monocyte surface membrane was determined in the absence and presence of insulin (10-100 mU/l) using flow cytometry. Anti-CD14-PE monoclonal antibody was used for monocyte gating. GLUT isoforms were determined after staining the cells with specific antisera to GLUT1, GLUT3 and GLUT4. RESULTS: Hyperthyroidism increased basal monocyte-surface GLUT1, GLUT3 and GLUT4 transporters. In these cells, insulin had a marginal effect on GLUT4 translocation (25 %, p < 0.02) and a more significant effect on GLUT3 translocation (45 %, p < 0.001) on plasma membrane. CONCLUSIONS: In the hyperthyroid state, (1) basal abundance of GLUT1, GLUT3 and GLUT4 transporters on the cell surface is increased; (2) insulin mainly increases the recruitment of GLUT3 and, to a lesser extent, GLUT4 glucose transporters on the plasma membrane. These findings may provide a mechanism to explain the increment of glucose disposal in peripheral tissues in hyperthyroidism.

Human leukocyte antigens as genetic markers in Greek patients with sporadic pancreatic cancer.

PURPOSE: In this study we investigated the relationship between specific HLA antigens and sporadic pancreatic cancer in Greek population. METHODS: The allele frequencies of serologically and molecular defined class I and II HLA antigens were studied in 60 unrelated patients with pancreatic cancer histologically confirmed. The results obtained for HLA frequencies were compared with those of 105 healthy control subjects (control group). RESULTS: Increased frequencies of HLA-A30 (16.7 vs. 3.8%; P < 0.01; OR = 5.05), A31 (9.5 vs. 1.9%; P < 0.05; OR = 5.72), B18 (31.7 vs. 14.3%; P < 0.05; OR = 2.78) and Cw7 (53.3 vs. 21.9%; P < 0.01; OR = 4.07) were observed in patients with pancreatic cancer in comparison to the control subjects. CONCLUSIONS: This study demonstrates the association between specific HLA antigens and pancreatic cancer development in whites and suggests a genetic susceptibility factor for the disease.

HLA-DPB1 alleles association of anticardiolipin and anti-beta2GPI antibodies in a large series of European patients with systemic lupus erythematosus.

Our objective was to determine the HLA-DPB1 allele associations of anticardiolipin (aCL) and anti-beta2GPI (a(beta)2GPI) antibodies, and of clinical manifestations of the antiphospholipid syndrome (APS), in systemic lupus erythematosus (SLE). We studied 577 European patients with SLE. aCL and a(beta)2GPI antibodies were measured by ELISA. Molecular typing of HLA-DPB1 locus was performed by polymerase chain reaction-sequence specific oligonucleotide probe (PCR-SSOP) method. aCL showed positive association with -DPB1*1501 (P = 0.005, OR = 7.4), and -DPB1*2301 (P = 0.009, OR = 3.3). a(beta)2GPI showed positive association with -DPB1*0301 (P = 0.01, OR = 1.9), and -DPB1*1901 (P = 0.004, OR = 8.1). In addition, livedo reticularis was associated with -DPB1*1401, and Raynaud's phenomenon with -DPB1*2001. In conclusion, HLA-DPB1 locus may contribute to the genetic predisposition to develop antiphospholipid antibodies and clinical manifestations of the APS in patients with SLE.

HLA phenotypes as promoters of cardiovascular remodelling in subjects with arterial hypertension.

The objective of this study was to investigate the association between human leukocyte antigens (HLA) phenotypes and cardiovascular remodelling, as expressed by left ventricular mass (LVM) and carotid intima-media thickness (IMT), in hypertensives. We examined 153 subjects with arterial hypertension and 61 normotensive controls living in the greater Athens area. The population was classified into three groups and specifically group I (normotensives), group II with Grade 1 hypertension and group III with Grade 2 or 3 hypertension. HLA class I and class II antigens were studied by microlymphocytotoxic technique. Carotid IMT and LVM were determined by ultrasonography. The prevalence of HLA DQ7 in the hypertensive cohort was 27.4% that was significantly smaller than the 52.5% among the controls (P = 0.002). The HLA DR11 was found in 24.0% of the hypertensives and in 52.5% of the controls (P < 0.001). Group III hypertensives with HLA DR11 exhibited significantly higher LVM/h in comparison to the hypertensives without this HLA (199.0 +/- 28.8 vs 171.2+44.1g/m, P = 0.009). This association was not present in groups I and II. Similarly, group III hypertensives with HLA DQ7 were characterized by higher IMT in comparison to those without this HLA (0.94 +/- 0.19 vs 0.83 +/- 0.23 mm, P = 0.048). HLA DR17 was associated with higher IMT in both groups II and III (1.00 +/- 0.19 vs 0.82 +/- 0.19 mm, P = 0.046 and 1.01 +/- 0.23 vs 0.84 +/- 0.22 mm, P = 0.049, respectively) but not in group I. In conclusion, certain HLA phenotypes may be related to the levels of arterial blood pressure. Moreover, it seems that these HLA phenotypes may identify subjects with arterial hypertension that are more prone to develop cardiovascular hypertrophy.

Atherosclerosis of carotid arteries and the ace insertion/deletion polymorphism in subjects with diabetes mellitus type 2.

BACKGROUND: The aim of the present study was to investigate the association of the angiotensin-converting enzyme (ACE) insertion/deletion (I/D) polymorphism with the ultrasonographically evaluated severity and characteristics of carotid artery atherosclerosis in subjects with diabetes mellitus type 2. METHODS: We assessed 184 subjects with diabetes mellitus type 2, 75 males and 109 females, mean age 61.4+/-7.7 years. All subjects were receiving oral antidiabetic drugs for glycemic control and were free of cardiovascular events. The ACE genotype was analyzed by the polymerase chain reaction (PCR) technique. The ultrasonographic examination of the carotid arteries was performed in both B-mode imaging and Doppler ultrasound. The common carotid artery intima-media thickness was assessed 15-20 mm proximal to the dilatation of the carotid bulb. The atheromatous lesions were classified according to their echogenic characteristics as predominantly echolucent, mixed and predominantly echogenic with under 30, 30-70 and over 70% of the total plaque area echogenicity, respectively. RESULTS: From the total cohort 29 (15.8%) subjects had the II, 86 (46.7%) the ID and 69 (37.5%) the DD ACE genotypes. The mean carotid artery diameter stenosis was 37+/-17%, 43+/-19% and 40+/-20% (p=NS) and the intima media thickness was 0.94+/-0.24 mm, 0.97+/-0.20 mm and 0.98+/-0.20 mm (p=NS) in the II, ID and DD subgroups, respectively. When the echogenicity was analyzed according to the ACE I/D polymorphism, 12 subjects (41.4%), 13 (44.8%) and 4 (13.8%) with II genotype had predominantly echogenic, mixed and predominantly echolucent lesions, respectively. The ID genotype diabetics were found to have predominantly echogenic plaques in 41 cases (47.7%), mixed in 30 (34.9%) and predominantly echolucent in 15 cases (17.4%). From the 69 DD subjects 19 (27.5%) had predominantly echogenic plaques, 26 (37.7%) had mixed and 24 (34.8%) had predominantly echolucent lesions. Predominantly echolucent plaques were more frequently encountered among diabetics with the DD genotype (p<0.05), even after correction for demographic characteristics, the main risk factors of atherosclerosis and blood glucose control. CONCLUSIONS: The ACE genotype seems to be associated with the echogenicity of carotid artery atheromatosis but not with the common carotid artery intima media thickness or the degree of internal carotid artery stenosis in subjects with type 2 diabetes mellitus. The DD genotype may be implicated in the increased cardiovascular risk that characterizes echolucent plaques.

Association of the HLA antigens with early atheromatosis in subjects with type 2 diabetes mellitus.

BACKGROUND: Inflammation plays an important role in the pathogenesis of atherosclerosis. The major histocompatibility complex, as expressed by the human leukocyte antigens (HLA) is considered to regulate the immune response. The aim of this study was to investigate the association of the HLA antigens with vascular remodeling estimated by the carotid intima-media thickness (IMT) in subjects with type 2 diabetes mellitus (DM). METHODS: We evaluated 197 patients with type 2 DM, 80 males and 117 females, mean age 61.8+/-7.8 years, with no history of cardiovascular events. The presence of other major cardiovascular risk factors was recorded. The currently identified HLA class I (-A, -B, -Cw) and class II (DR, -DQ) antigens were studied by a classical 2 step microlymphocytotoxic technique in peripheral blood T and B lymphocytes. Measurements of the IMT were performed in the right and left common carotid arteries, 15-20 mm proximal to the dilatation of the carotid bulb in an end-diastolic "frozen" and magnified B-mode ultrasonographic image. Glycosylated hemoglobin A1c (HbA1c) and C-reactive protein (CRP) were also measured. The results are presented as mean +/-1 standard deviation. RESULTS: Regarding the HLA phenotypes in the final analysis we tested a total of 24 HLA antigens that exhibited a frequency of at least 5% in our diabetic population. Only HLA A3 was found to be significantly associated with the carotid IMT. Forty-nine (24.9%) diabetics were HLA A3 positive (group A), while 148 (75.1%) were HLA A3 negative (group B) and had mean IMT of 0.89+/-0.16 mm and 0.98+/-0.21 mm, respectively (p<0.01). Also the two groups differed significantly in respect to CRP, with group A exhibiting lower serum levels (1.1+/-0.4 mg/dl vs 2.6+/-0.7 mg/dl for group A and B, respectively, p<0.05). However, no differences were observed between the two groups as far as blood glucose control, arterial hypertension and dyslipidaemia were concerned. CONCLUSIONS: Human leukocyte antigen A3 is associated with less vascular damage, as expressed by carotid wall thickness, in subjects with type 2 DM. These subjects may be characterized by a milder inflammatory response, as shown by the lower serum levels of CRP.

Association of specific HLA phenotypes with left ventricular mass and carotid intima-media thickness in hypertensives.

The aim of this study was to investigate the hypothesis that the expression of certain HLA antigens may constitute a risk marker for cardiovascular hypertrophy in subjects with arterial hypertension. We examined 158 subjects with newly diagnosed arterial hypertension. HLA class I (-A, -B, -Cw) and class II (-DR, -DQ) antigens were studied by two-step microlymphocytotoxic technique in peripheral T and B lymphocytes. Carotid intima-media thickness (IMT) was determined noninvasively by ultrasonography. The left ventricular mass was calculated according to the formula of Devereux and was normalized by the individual's height (LVM/h). The individuals with DR13 and DR17 were characterized by higher values of IMT compared to those without these HLA (0.096+/-0.018 cm v 0.085+/-0.021 cm, P = .011, 0.100+/-0.019 cm v 0.084+/-0.021 cm, P = .012, respectively). The presence of HLA DQ7 was characterized by markedly higher values of IMT that just failed to reach statistical significance (0.091+/-0.019 cm v 0.084+/-0.022 cm, P = .045). Furthermore, subjects with HLA DQ7 and DR11 exhibited higher values of LVM/h in comparison to those without these HLA (191.3+/-36.2 g/m v 166.9+/-41.0 g/m, P = .029 and 194.6+/-34.3 g/m v 166.6+/-40.9 g/m, P = .034, respectively). Hypertensive subjects with HLA B51 tended to have lower LVM/h (166.6+/-39.0 g/m with v 176.0+/-41.7 g/m without HLA B51, P = .045). In conclusion, it can be postulated that certain HLA phenotypes exhibit an association with increased carotid IMT and left ventricular mass in hypertensive subjects. The determination of these antigens may help to identify subjects at high risk for cardiovascular events.

Allergy to olive pollen: a study of four family members.

We describe four family members with respiratory and dermatological manifestations of olive pollen allergy. The purpose of this study was 1) to investigate whether these patients' sera react to the same or different olive allergens, and 2) to identify common HLA class II antigens.

TCRgammadelta + T lymphocytes in unexplained recurrent spontaneous abortions.

PROBLEM: It is generally accepted that the immune system and cellular immunity in particular are involved in the mechanisms affecting the outcome of gestation. In order to evaluate a putative role of lymphocytes in the immunological mechanisms of unexplained recurrent spontaneous abortions (URSA), we studied peripheral blood lymphocyte subpopulations in 244 women with URSA and 44 controls. METHOD OF STUDY: Direct immunofluorescence in whole blood with the appropriate combinations of monoclonal antibodies and flow cytometry was used. RESULTS: The study showed: a) a statistically significant increase of the mean CD4/CD8 ratio (2.12+/-0.84 vs 1.85+/-0.63, P = 0,039); b) a statistically significant decrease of the mean value of the percentage of CD5+ CD19+ lymphocytes (0.4+/-0.6 vs 1.4+/-0.78, P < 0.0001); and c) a statistically significant increase of the percentage of T lymphocytes expressing TCRgammadelta (4.68+/-3.19 vs 2.61+/-1.14, P < 0.0001). It should be noted that a statistically significant high number of women with URSA (72/195, 36.9%) showed an increased percentage of TCRgammadelta T cells (> or = 5%, where 5 equals the mean value + 2 standard deviations (SD) of the mean value of controls), whereas such a high percentage was not found in any control subject. CONCLUSIONS: It seems that women who experienced URSA comprise a heterogeneous population, as far as immunological parameters are concerned. At least in a subgroup of them, TCRgammadelta + T cells could be considered to play a role in the immune pathogenesis of fetal loss.

Thyroid autoimmunity in patients with recurrent spontaneous miscarriages.

Recurrent spontaneous miscarriage (RSM) is a multifactorial problem. Auto- and alloimmune parameters have been implicated. Antithyroid antibodies (ATA) were tested in a group of women with RSM. The presence of antipaternal antibodies (APCA) was evaluated as an index of alloimmune contribution. Thirty euthyroid women with RSM (three or more consecutive miscarriages) aged 25-37 years were compared with 15 matched controls. Thyroid peroxidase (TPO) and thyroglobulin antibodies were tested with a chemiluminescence immunoassay and APCA were tested with a cross-match reaction. Results were compared using the chi-squared test. There was a higher frequency of ATA in women with RSM compared to controls (37% versus 13%, p < 0.05). Twenty of the women (67%) with RSM were tested negative for APCA, indicating an alloimmune contribution to their infertility. In this subgroup of women, the frequency of ATA continued to be higher than controls (40% versus 13%, p < 0.05). In conclusion, women with RSM, independent of APCA status, have a higher frequency of ATA. This may represent an additional marker for impaired regulation of the maternal immune system.