SNPs, adipokynes and adiposity in children with asthma.

OBJECTIVES: Asthma and obesity are complex disorders influenced by environmental and genetic factors. We performed an integrative review of genetic polymorphisms and adipokines effects in children and adolescents with asthma and obesity. DATA SOURCES: Articles focused on these issues were collected from SciELO, PubMed, LILACS, Embase and ScienceDirect electronic databases, in 2009-2020 period. STUDY SELECTIONS: 22 articles were selected, including clinical trials, analyses approaches, case-control studies, meta-analysis and Mendelian randomization studies. RESULTS: Leptin concentrations were higher in obesity and asthma. The high value of BMI and Leptin indicated severe asthma. Adiponectin may be reduced in obese children. The high value of BMI and low level of Adiponectin may indicate severe asthma. Some linkage of PRKCA gene, asthma and BMI was observed. FTO T allele rs62048379 was positively associated with overweight/obesity, related to protein and PUFA:SFA ratio intake and influences the choice of more energy-dense foods. FTO rs9939609 effects are more pronounced among children with insufficient vitamin D levels. CONCLUSION: Leptin may be a potential predictor for asthma control in children. BMI and Adiponectin could have certain predictive value for asthma. FTO gene was related to a higher mean BMI Z-score and accelerated developmental age per allele. Strong genetic heterogeneity influencing on asthma and obesity susceptibilities is evident and related to distinct genetic features. GWAS with childhood obesity in asthma contributed to greater insights, mainly on later childhood. Standardized definitions for asthma and overweight/obesity in studies approaching adipokines and SNPs would provide stronger evidence in deciding the best management.

Severe cutaneous adverse drug reactions: diagnostic approach and genetic study in a Brazilian case series.

Summary: Background. Severe cutaneous adverse reactions (SCAR) are potentially fatal reactions. Genetic predisposition is involved in their pathogenesis related to drugs and ethnicities, however in a mixed population these relationships are still unknown. The aim of this study was to describe phenotypes, suspect drugs and HLA-alleles related to SCAR, identified by a systematized approach in a Brazilian case series. Methods. Patients who were diagnosed with SCAR between March 2011 and July 2019 at our university hospital were included. European Network for Drug Allergy (ENDA) questionnaire was used to collect clinical and laboratory data and algorithms for assessment of drug causality were applied. Socio-demographic variables included age, gender and skin color/ethnicity. Drug patch tests (DPT) and HLA-A, -B, -DRB1 typing were carried out. Results. A total of 74 patients were included: 36 (48.64%) with SJS/TEN, 32 (43.24%) DRESS/DIHS, 3 (4.05%) AGEP, 2 (2.70%) overlap(DRESS/SJS and DRESS/AGEP) and 1 (1.35%) GBFDE. The median age was31.5 years (IQR = 14-52.25), most were female (n = 44/59.46%) and brown (n = 38/51.35%). Anticonvulsants (n = 32/43.24%) were the largest group involved and antibiotics (n = 26/35.13%) were the second most common. Two patients with DRESS died during the acute phase. Positive DPT were shown only in anticonvulsant associated DRESS. HLA related to abacavir, allopurinol and carbamazepine were identified. Conclusions. A systematized approach allowed the phenotypic characterization of SCAR. The HLA-A*31:01, B*57:01 and B*58:01 alleles were identified, reinforcing the causality in SCAR by CBZ, ABC and ALLO in the Brazilian population.

Genomic ancestry and metabolic syndrome in individuals with type 1 diabetes from an admixed population: a multicentre, cross-sectional study in Brazil.

AIMS: To evaluate the relationship between self-reported colour-race, genomic ancestry, and metabolic syndrome in an admixed Brazilian population with type 1 diabetes. METHODS: We included 1640 participants with type 1 diabetes. The proportions of European, African and Amerindian genomic ancestries were determined by 46 ancestry informative markers of insertion deletion. Two different sets of analyses were performed to determine whether self-reported colour-race and genomic ancestry were predictors of metabolic syndrome. RESULTS: Metabolic syndrome was identified in 29.8% of participants. In the first model, the factors associated with metabolic syndrome were: female gender (odds ratio 1.95, P < 0.001); diabetes duration (odds ratio 1.04, P < 0.001); family history of type 2 diabetes (odds ratio 1.36, P = 0.019); and acanthosis nigricans (odds ratio 5.93, P < 0.001). Colour-race was not a predictive factor for metabolic syndrome. In the second model, colour-race was replaced by European genomic ancestry. The associated factors were: female gender (odds ratio 1.95, P < 0.001); diabetes duration (odds ratio 1.04, P < 0.001); family history of type 2 diabetes (odds ratio 1.39, P = 0.011); and acanthosis nigricans (odds ratio 6.12, P < 0.001). Physical exercise (≥3 times a week) was a protective factor (odds ratio 0.77, P = 0.041), and European genomic ancestry was not associated with metabolic syndrome but showed an odds ratio of 1.77 (P = 0.05). CONCLUSIONS: Although a higher level of European genomic ancestry was observed among participants with metabolic syndrome in the univariate analysis, this association did not persist after multivariable adjustments. Further prospective studies in other highly admixed populations remain necessary to better evaluate whether the European ancestral component modulates the development of metabolic syndrome in type 1 diabetes.

Soluble CD30, Acute Rejection, and Graft Survival: Pre- and 6-Month Post-Transplant Determinations-When Is the Best Time to Measure?

BACKGROUND: Pretransplantation soluble CD30 (sCD30) has been shown to be a good predictor of acute rejection (AR) and graft loss. This study aimed to evaluate the effectiveness of sCD30 measured pretransplant and up to 6 months after transplantation as a predictor of AR, graft loss, and survival at 5 years post-transplantation. Subjects were patients receiving living donor renal transplants at Bonsucesso Federal Hospital (Rio de Janeiro) in 2006 and between August 2010 and May 2011. METHODS: sCD30 was analyzed in samples collected pretransplantation and 7, 14, and 21, 28 days and 3, 4, 5, and 6 months post-transplantation from 73 kidney recipients. RESULTS: Patients in the AR group did not present a positive correlation with the sCD30 levels pretransplant (P = .54); in the post-transplant period, the 7- to 14-day samples showed patients with AR had higher levels of this biomarker (P = .036). The graft survival in 5 years of follow-up was not different between groups. CONCLUSIONS: The best time to predict AR using sCD30 is the 7- to 14-day sample; however, identifying and following the decrease of this biomarker from pre- to post-transplant seems to be better than just 1 measurement. The sCD30 post-transplant is another tool that may be used in monitoring patients after renal transplantation.

Killer cell immunoglobulin-like receptor (KIR) gene diversity in a population naturally exposed to malaria in Porto Velho, Northern Brazil.

Killer cell immunoglobulin-like receptors (KIR) are expressed mainly in natural killer cells and specifically recognize human leukocyte antigen (HLA) class I molecules. The repertoire of KIR genes and KIR-HLA pairs is known to play a key role in the susceptibilities to and the outcomes of several diseases, including malaria. The aim of this study was to investigate the distribution of KIR genes, KIR genotypes and KIR-HLA pair combinations in a population naturally exposed to malaria from Brazilian Amazon. All 16 KIR genes investigated were present in the studied population. Overall, 46 KIR genotypes were defined. The two most common genotypes in the Porto Velho communities, genotypes 1 and 2, were present at similar frequencies as in the Americas. Principal component analysis based on the frequencies of the KIR genes placed the Porto Velho population closer to the Venezuela Mestizos, USA California hispanic and Brazil Paraná Mixed in terms of KIR gene frequencies. This analysis highlights the multi-ethnic profile of the Porto Velho population. Most of the individuals were found to have at least one inhibitory KIR-HLA pair. Seventy-five KIR-HLA pair combinations were identified. The KIR-2DL2/3_HLA-C1, KIR3DL1_HLA-Bw4 and KIR2DL1_HLA-C2 pairs were the most common. There was no association between KIR genes, KIR genotypes or KIR-HLA pair combinations and malaria susceptibility in the studied population. This is the first report on the distribution of KIR and known HLA ligands in the Porto Velho population. Taken together, these results should provide baseline information that will be relevant to population evolutionary history, malaria and other diseases studies in populations of the Brazilian Amazon.

A possible relationship of human leucocyte antigens with psoriasis vulgaris and geographic tongue.

BACKGROUND: Geographic tongue (GT) is the most frequent oral lesion in psoriatic patients (PP), and genetic involvement in these conditions has been described. The association of psoriasis with GT is still not clear, and the study of human leucocyte antigen (HLA) may help clarify this relation. OBJECTIVE: The aim of this study was to investigate the association of HLA alleles with psoriasis vulgaris and GT. METHODS: Fifty-eight Brazilian PP, 29 GT patients and 125 healthy controls individuals were selected. Information on demographic and clinical characteristics was collected. All patients underwent an oral examination and blood collection for HLA typing. RESULTS: HLA-A did not show significant differences in frequencies among the groups. HLA-B*57 allele was more frequently found in PP and was not found in GT. HLA-B*58 allele was more frequently found in GT. HLA-C*06 and -C*18 alleles were associated with psoriasis. No significant differences in HLA-DRB1 and HLA-DQB1 were observed. CONCLUSION: HLA-B*58 was associated with GT and HLA-B*57 was possibly associated with psoriasis. This suggested that some GT cases may represent true oral psoriasis and some may represent only GT. Therefore, it is necessary to make this distinction and increase our sample size to improve the correct diagnosis and treatment of these conditions.

Ethnicity and route of HCV infection can influence the associations of HLA with viral clearance in an ethnically heterogeneous population.

Approximately 20% of hepatitis C virus (HCV) infected individuals clear the virus. Host factors that influence the course of HCV infection are still under investigation, and the data on the association of human leukocyte antigen (HLA) alleles and HCV clearance are scarce and controversial. The aims of this study were to investigate whether HLA alleles are associated with clearance of HCV infection in a highly admixed Brazilian population and whether these associations could be influenced by ethnicity and route of infection. HLA-A, -B, -C, -DRB1 and -DQB1 genotyping were performed in 135 HCV-infected Brazilian patients among which 45 cleared HCV infection (cases) and 90 had persistent viral infection (controls). Controls were matched by sex, ethnicity (withes and non-whites) and route of infection (high infectious dose or low infectious dose). No significant association was identified between HLA alleles and the outcome of HCV infection when analyzing the sample as a single group. However, a new protective association of HLA-DQB1*04 (P = 0.006; P(c) = 0.030) and a rarely described association of HLA-DRB1*08 (P = 0.004; P(c) = 0.048) were found only among white patients. The DRB1*11 allele, previously reported in homogeneous population, was associated with HCV clearance (P = 0.020) only among patients with expected high-dose exposure. These findings confirm the influence of ethnicity on the associations of HLA with spontaneous viral clearance of HCV infection and emphasize the possible influence of route of infection in this process.

α-smooth muscle actin, fibrillin-1, apoptosis and proliferation detection in primary varicose lower limb veins of women.

AIM: The role of SMC apoptosis and proliferation was correlated to the amount of fibrillin and alfa-smooth muscle actin of primary varicose veins. METHODS: Twenty varicose vein specimens were atraumatically harvested from 20 women undergoing lower extremity primary varicose vein excision. The patients were divided into groups according to age (<50 years, >50 years) and the presence of leg edema (CEAP, class 2 or 3). The surface density of fibrillin-1 fibers (Sv([Fbn-1])), the volume density of smooth muscle cells: (Vv([SMC])), the number of proliferating and apoptotic cells per area. Quantitative data comparisons between class and age groups were performed. RESULTS: The median value of Vv([SMC]) was 16% greater and the Sv([Fbn-1]) was 35% greater in the intima vein sections from patients up to 50y compared to >50y. Apoptosis was found more frequent in veins sections from varicose women >50y. In the media layer, Sv([Fbn-1]) in veins from patients up to 50y was more important, and women with >50y had also more cells in apoptosis. Vv([SMC]) from women without edema (CEAP-Class 2) was 28% greater in the intima and apoptotic cells were more prominent in the intima of women with edema (CEAP-Class 2). In the media layer, Sv([Fbn-1]) was 12,5% greater in veins from women without edema and apoptosis was more detected in the veins from patients with edema. CONCLUSION: Age of the patient may affect the remodeling of varicose veins and SMC quantity in the media layer was found decreased in patients with edema.

Decrease in oxidative stress and histological changes induced by physical exercise calibrated in rats with osteoarthritis induced by monosodium iodoacetate.

OBJECTIVE: The purpose of this study was to evaluate the effects of impact exercise on the joint cartilage of rats with osteoarthritis (OA) induced by monosodium iodoacetate (MIA). METHODS: Eighteen male rats were divided into three groups of six animals each: control, OA, and OA plus exercise (OAE). The OAE group trained on a treadmill for 8 weeks. Afterward, the right joints of the animals were washed with saline solution and joint lavage was used for biochemical analyses of myeloperoxidase (MPO) and enzyme superoxide dismutase (SOD) activities and total thiol content. The same limb provided samples of the articular capsule for analyses of MPO activity and total thiol content. The left joint was used for histological analysis. RESULTS: Our results indicate that MPO activity was increased in both OA groups in the lavage as well as the articular capsule, regardless of exercise status. SOD activity was increased in animals with OA, especially in the animals that had run on the treadmill. On the other hand, thiol content in the articular capsule and joint lavage decreased in the OA group, while the OAE group had values similar to those of the control group. The histological data indicate that animals that were submitted to running exercise showed a higher preservation rate of proteoglycan content in the superficial and intermediate areas of the joint cartilage. CONCLUSION: Our results show that physical training contributes to the preservation of joint cartilage in animals with OA and to increase the defense mechanism against oxidative stress.

Promiscuous T-cell epitopes of Plasmodium merozoite surface protein 9 (PvMSP9) induces IFN-gamma and IL-4 responses in individuals naturally exposed to malaria in the Brazilian Amazon.

Plasmodium vivax merozoite surface protein (PvMSP9) stimulates both cellular and humoral immune responses in individuals who are naturally infected by this parasite species. To identify immunodominant human T-cell epitopes in PvMSP9, we used the MHC class II binding peptide prediction algorithm ProPred. Eleven synthetic peptides representing predicted putative promiscuous T-cell epitopes were tested in IFN-gamma and IL-4 ELISPOT assays using peripheral blood mononuclear cells (PBMC) derived from 142 individuals from Rondonia State, Brazil who had been naturally exposed to P. vivax infections. To determine whether the predicted epitopes are preferentially recognized in the context of multiple alleles, MHC Class II typing of the cohort was also performed. Five synthetic peptides elicited robust cellular responses, and the overall frequencies of IFN-gamma and IL-4 responders to at least one of the promiscuous peptides were 62% and 46%, respectively. The frequencies of IFN-gamma and IL-4 responders to each peptide were not associated with a particular HLA-DRB1 allelic group since most of the peptides induced a response in individuals of 12 out of 13 studied allelic groups. The prediction of promiscuous epitopes using ProPred led to the identification of immunodominant epitopes recognized by PBMC from a significant proportion of a genetically heterogeneous population exposed to malaria infections. The combination of several such T-cell epitopes in a vaccine construct may increase the frequency of responders and the overall efficacy of subunit vaccines in genetically distinct populations.

Report from the killer immunoglobulin-like receptor (KIR) anthropology component of the 15th International Histocompatibility Workshop: worldwide variation in the KIR loci and further evidence for the co-evolution of KIR and HLA.

The killer immunoglobulin-like receptor (KIR) anthropology component of the 15th International Histocompatibility Workshop (IHIWS) sought to explore worldwide population variation in the KIR loci, and to examine the relationship between KIR genes and their human leukocyte antigen (HLA) ligands. Fifteen laboratories submitted KIR genotype and HLA ligand data in 27 populations from six broad ethnic groups. Data were analyzed for correlations between the frequencies of KIR and their known HLA ligands. In addition, allelic typing was performed for KIR2DL2 and 3DL1 in a subset of populations. Strong and significant correlations were observed between KIR2DL2, 2DL3 genotype frequencies and the frequency of their ligand, HLA-C1. In contrast, only weak associations were seen for 3DL1, 3DS1 and the HLA-Bw4 ligand. Although some aspects of the correlations observed here differ from those reported in other populations, these data provide additional evidence of linked evolutionary histories for some KIR and HLA loci. Investigation of allele-level variation for the B haplotype locus KIR 2DL2 showed that two alleles, *001 and *003, predominate in all populations in this study. Much more allelic variation was observed for the A haplotype locus 3DL1, with several alleles observed at moderate frequencies and extensive variation observed between populations.

Evaluations of bioantioxidants in cryopreservation of umbilical cord blood using natural cryoprotectants and low concentrations of dimethylsulfoxide.

Transplantation using hematopoietic stem cells from umbilical cord blood (UCB) is a life-saving treatment option for patients with select oncologic diseases, immunologic diseases, bone marrow failure, and others. Often this transplant modality requires cryopreservation and storage of hematopoietic stem cells (HSC), which need to remain cryopreserved in UCB banks for possible future use. The most widely used cryoprotectant is dimethylsulfoxide (Me(2)SO), but at 37 degrees C, it is toxic to cells and for patients, infusion of cryopreserved HSC with Me(2)SO has been associated with side effects. Freezing of cells leads to chemical change of cellular components, which results in physical disruption. Reactive oxygen species (ROS) generation also has been implicated as cause of damage to cells during freezing. We assessed the ability of two bioantioxidants and two disaccharides, to enhance the cryopreservation of UCB. UCB was processed and subjected to cryopreservation in solutions containing different concentrations of Me(2)SO, bioantioxidants and disaccharides. Samples were thawed, and then analysed by: flow cytometry analysis, CFU assay and MTT viability assay. In this study, our analyses showed that antioxidants, principally catalase, performed greater preservation of: CD34+ cells, CD123+ cells, colony-forming units and cell viability, all post-thawed, compared with the standard solution of cryopreservation. Our present studies show that the addition of catalase improved the cryopreservation outcome. Catalase may act on reducing levels of ROS, further indicating that accumulation of free radicals indeed leads to death in cryopreserved hematopoietic cells.

Evaluation of trehalose and sucrose as cryoprotectants for hematopoietic stem cells of umbilical cord blood.

Bone marrow transplantation (BMT) is a therapeutic procedure that involves transplantation of hematopoietic stem cells (HSC). To date, there are three sources of HSC for clinical use: bone marrow; mobilized peripheral blood; and umbilical cord blood (UCB). Depending on the stem cell source or type of transplantation, these cells are cryopreserved. The most widely used cryoprotectant is dimethylsulfoxide (Me(2)SO) 10% (v/v), but infusion of Me(2)SO-cryopreserved cells is frequently associated with serious side effects in patients. In this study, we assessed the use of trehalose and sucrose for cryopreservation of UCB cells in combination with reduced amounts of Me(2)SO. The post-thawed cells were counted and tested for viability with Trypan blue, the proportion of HSC was determined by flow cytometry, and the proportion of hematopoeitic progenitor cells was measured by a colony-forming unit (CFU) assay. A solution of 30mmol/L trehalose with 2.5% Me(2)SO (v/v) or 60mmol/L sucrose with 5% Me(2)SO (v/v) produced results similar to those for 10% (v/v) Me(2)SO in terms of the clonogenic potential of progenitor cells, cell viability, and numbers of CD45(+)/34(+) cells in post-thawed cord blood cryopreserved for a minimum of 2 weeks. Thus, cord blood, as other HSC, can be cryopreserved with 1/4 the standard Me(2)SO concentration with the addition of disaccharides. The use of Me(2)SO at low concentrations in the cryopreservation solution may improve the safety of hematopoietic cell transplantation by reducing the side effects on the patient.

Psoriasis vulgaris and human leukocyte antigens.

BACKGROUND: Psoriasis vulgaris is a skin disease with a complex immunological and genetic background, triggered by environmental factors. The association of human leukocyte antigens (HLA) and psoriasis has long been reported on population and familial studies. OBJECTIVES: To review and discuss studies on psoriasis vulgaris and HLA, in Caucasian and non-Caucasian populations. METHODS: The major population studies on psoriasis vulgaris and the associated HLA antigens and alleles are described and discussed based on a review of the current literature. RESULTS: Population studies demonstrate the presence of different HLA specificities as well as extended haplotypes in patients with psoriasis, when compared to controls. Some alleles occur in a lower frequency in patients with psoriasis, indicating they could be protection alleles. In all studies which HLA class I was typed, Cw6 or Cw*0602 was present in a significant frequency in patients with psoriasis, mainly when early onset and positive family history were considered. HLA-DRB1*0701 was also present in a higher frequency in patients in different populations. CONCLUSIONS: Different antigens and alleles from both HLA classes I and II were seen in a significantly higher frequency in patients with psoriasis vulgaris. HLA Cw*0602 and DRB1*0701 were represented in different reports, and the former was related mainly to psoriasis type I.

Correlation between HLA and pityriasis rosea susceptibility in Brazilian blacks.

OBJECTIVES: The human leucocyte antigen (HLA) has been related to susceptibility factors in several diseases. This study aimed to determine the potential genetic susceptibility of patients with pityriasis rosea (PR) through HLA molecular typing analysis. METHODS: The method of choice was polymerase chain reaction with sequence-specific primers (PCR-SSP) using low-resolution typing kits, with determination of the alleles class I (HLA-A, HLA-B and HLA-C) and class II (HLA-DRB1, DRB3, DRB4, DRB5 and DQB1) performed in 30 Afro-Brazilian PR-diagnosed patients and 45 healthy individuals as the control group (PR-C). RESULTS: Analysis of the HLA typing results showed that the relative risk (RR) of 4.00 [95% confidence interval (95% CI) 1.20-13.28, two-tailed P = 0.018] for allele HLA-DQB1*04 class II, detected in 33.3% of PR patients, was significant. By contrast, in the control group only 11.1% of subjects had that allele. Three out of six B*51 alleles and three out of six B*53 alleles detected in PR patients were found, together with the allele DQB1*04. CONCLUSION: We suggest that alleles DQB1*04 may be involved in the genetic susceptibility of PR based on the significant predominance of those alleles observed in the black PR patients. We also recommend that more studies are conducted on populations of other ethnic origins, preferentially with higher resolution techniques of DNA typing.

Contractile cells and fibrillin-1 distribution is disturbed in terminal villi of placentae from patients with preeclampsia and systemic lupus erythematosus.

Placentae from patients with preeclampsia (PE) and systemic lupus erythematosus (SLE) present many alterations that may impair materno-fetal exchange. We investigated the distribution of contractile cells and fibrillin-1 in terminal villi of term placentae from patients with PE or SLE and compared to control placentae. Stroma in terminal villi exhibited intense labelling for fibrillin-1. The fibrillin-1 villi surface fraction was greater in PE and SLE placentae than in controls (13+/-0.4%, 14+/-0.5%, 10+/-0.4%; p=0.0001). Immunohistochemistry for alpha-smooth muscle (SM) actin showed few contractile cells in control terminal villi stroma, localized around fetal capillaries and showed rare processes in vasculo-syncytial membrane. PE and SLE placentae exhibited an increase in the number of capillaries presenting alpha-SM actin adventitial positive cells. The presence of alpha-SM actin processes interposed in the vasculo-syncytial membrane was greater in SLE villi than in PE and controls. Ultrastructural observations confirmed in SLE and PE terminal villi the presence of these processes in vasculo-syncytial membrane and also showed a thickened trophoblastic basement membrane. The present study demonstrates that an important myofibroelastic system is present in term terminal villi, and that this system is actively remodelled in PE and SLE placentae.

Molecular and morphologic analyses of expression of ESX1L in different stages of human placental development.

The mRNA expression of the ESX1L gene was analyzed by RT-PCR and in situ hybridization in human normal cytogenetically placentas, of different gestational ages. Our RT-PCR analysis showed that ESX1L mRNA is expressed from 5 weeks of gestation until term, suggesting a role not only in trophoblast differentiation but also in the maintenance of the villi and microvasculature. We also observed, by in situ hybridization, that ESX1L mRNA is expressed by cytotrophoblast from chorionic plate, syncytiotrophoblast and stromal cells of all terminal, intermediate and stem villi of term placentas. ESX1L mRNA expression was more pronounced in trophoblast cells of terminal villi than in intermediate and stem villi. In conclusion, ESX1L is expressed during all stages of placental development and is localized to sparse areas of trophoblast in terminal villi in association with cytotrophoblastic cells.

Differential expression of laminin isoform (alpha2), integrins (alpha3beta1 and alpha6beta4) and cytokeratin 20 in H. pylori gastritis.

The expression of laminin-1 chains (beta1 and gamma1), laminin-2 (merosin), integrin receptors to laminin (alpha3beta1 and alpha6beta4) and cytokeratin (CK20) were studied by immunohistochemical methods in gastric biopsies from antrum of 25 patients. H. pylori gastritis was found in 19 cases and intestinal metaplasia (IM) in four from these 19. Another 13 biopsies, all with IM were immunostained to laminin-2. Laminin-1 chains in normal and gastritis areas without IM were expressed as a strong, linear and continuous deposit in the basement membranes of the superficial and glandular epithelium. In metaplastic glands the reactivity to laminin-1 chains was decreased. Merosin was discontinuous when a moderate to accentuated H. pylori glandular colonization was present. Samples with IM were negative to laminin-2. The alpha3beta1 and alpha6beta4 integrins were negative only in IM gastric biopsies. The CK20 immunoreactivity was strong and homogeneous in the cells at the tip and the upper portion of foveolae in normal areas and in gastritis with IM the reactivity to CK 20 was heterogeneous. A differential expression of laminin isoforms is related to inflammation and subsequent IM caused by H. pylori. The alterations of alpha3beta1 and alpha6beta4 parallel both modifications in merosin and CK20 expression in H. pylori chronic gastritis.

Detection and localization of non-HLA-ABC antigenic sites relevant to kidney rejection on endothelial cells.

Immunological rejection of kidney allografts is usually attributed to presensitization to HLA antigens. However, data on HLA identical transplant rejections indicate that non-HLA antigens may also be involved, and it has been suggested that vascular endothelium represents the main target cell. The purpose of the present study is to describe a method of detecting non-HLA antibodies immunocytochemically. We showed the molecular independence between HLA-ABC molecules identified by the monoclonal antibody w6/32, and antigenic sites identified by a kidney rejection patient serum, previously characterized, on cultured endothelial cells isolated from human umbilical cords by collagenase digestion. Single immunofluorescence staining indicated the molecular independence between these antigenic sites, as the first serum showed a granular pattern, diffused throughout the cytoplasm and the other a reticular pattern restricted to the same cytoplasmic region. This result was confirmed by double labeling. Immunoelectronmicroscopy study also confirmed site independence, showing labeling patterns with different intensities and distinct localizations, using 10- and 20-nm colloidal gold particles to reveal HLA-ABC and non-HLA-ABC determinants, respectively. In conclusion, cultured endothelial cells may be used immunocytochemically to detect non-HLA-ABC determinants of antibody reactivity in renal graft recipients, and the indirect immunofluorescence may be the methodology of choice, since it is easy, reliable and low cost.