Autoantibodies against zinc transporter 8 further stratify the autoantibody-defined risk for type 1 diabetes in a general population of schoolchildren and have distinctive isoform binding patterns in different forms of autoimmune diabetes: results from the Karlsburg Type 1 Diabetes Risk Study.

AIMS: To evaluate the diagnostic relevance of autoantibodies against zinc transporter 8 (ZnT8) in schoolchildren from the general population as well as in people with autoimmune diabetes. METHODS: A total of 137 schoolchildren positive for at least one of the three major diabetes-associated autoantibodies, without diabetes heredity or preselection on HLA typing, from the Karlsburg Type 1 Diabetes Risk Study, as well as 102 people at type 1 diabetes onset, 88 people with latent autoimmune diabetes in adults and 119 people with type 2 diabetes, were analysed for different ZnT8 autoantibody variants. RESULTS: Zinc transporter 8 autoantibody positivity was found in 18% of autoantibody-positive schoolchildren, with a noticeable association with other autoantibodies associated with type 1 diabetes and disease progression. Furthermore, ZnT8 autoantibody positivity was associated with diabetes progression in schoolchildren positive for autoantibodies against insulinoma-associated antigen-2 (IA-2) and, importantly, in seven IA-2 autoantibody-negative schoolchildren. Additionally, ZnT8 autoantibodies were found in 56% of people with type 1 diabetes, predominantly directed against all three ZnT8 variants and comparable to schoolchildren with multiple autoantibodies. In contrast, ZnT8 autoantibodies were detected in 10% of people with latent autoimmune diabetes in adults, none of them with reactivity to all three isoforms. CONCLUSION: Zinc transporter 8 autoantibodies are useful markers for prediction of type 1 diabetes in a general population, further stratifying the risk of progression in autoantibody-positive children. ZnT8 autoantibodies are also important markers in adult-onset diabetes, with a completely different reaction pattern in type 1 diabetes in comparison to latent autoimmune diabetes in adults, and may therefore help to differentiate between the two forms.

Methodological and clinical aspects of alloimmunization after granulocyte transfusion in patients undergoing allogeneic stem cell transplantation.

In allogeneic hematopoietic stem cell transplantation (HSCT), granulocyte transfusions (GT) may be required in immunocompromised, neutropenic patients. In this context, alloimmunization against alloantigens may occur and affect HSCT outcome. Anti-human leukocyte antigen (HLA) and -MHC class I chain related antigens A (MICA) antibody response after the administration of GT in 29 patients undergoing allogeneic HSCT (n = 27) encompassing 109 sera was investigated by multianalyte microbead assay before and up to 6 month after HSCT. Anti-HLA class I and II antibodies emerged de novo in 11 (38%) and 4 (14%) patients, respectively. Similarly, preformed antibodies were observed in four cases (14%) for anti-HLA class I and also four patients for anti-HLA class II antibodies. Anti-MICA antibodies were observed in eight granulocyte recipients of which three patients developed anti-MICA antibodies after GT, whereas preformed antibodies were seen in five patients. The conversion to positivity for any of the investigated antibodies did not significantly affect overall survival or the incidence of GVHD. GT-associated alloantibody conversion observed did not significantly correlate with outcome. Thus, surveillance of anti-HLA antibodies in the course of GT in the context of HSCT may not be required routinely. The role of MICA antibodies in HSCT and GT, however, requires further study.

Autoantibody-defined risk for Type 1 diabetes mellitus in a general population of schoolchildren: results of the Karlsburg Type 1 Diabetes Risk Study after 18 years.

AIMS: To investigate the occurrence of diabetes-associated autoantibodies and cumulative Type 1 diabetes risk over 18 years in a general population of schoolchildren. METHODS: In the Karlsburg Type 1 Diabetes Risk Study, 11 986 schoolchildren from north-eastern Germany without a family history of diabetes were screened for glutamic acid decarboxylase antibodies, insulinoma-associated antigen-2 antibodies and insulin autoantibodies by radioligand binding assay. Those children found to be autoantibody-positive were invited to follow-up examinations and HLA-DQB1 genotyping, and were followed for progression to Type 1 diabetes. RESULTS: At first follow-up, 119 children had single and 36 children had multiple autoantibodies. Of the multiple autoantibody-positive children, 33 had at least one diabetes-associated HLA-DQB1 allele (*02 and/or *0302). A total of 26 children progressed to Type 1 diabetes, of whom 22 had multiple autoantibodies. The male-to-female ratio of those who progressed to Type 1 diabetes was 1.6. The positive predictive value of multiple autoantibodies was 61.1% compared with only 23.7% for diabetes-associated HLA-DQB1 genotypes among all those who were autoantibody-positive. The cumulative risk was 59.7% after 10 years and 75.1% after 18 years for children with multiple autoantibodies compared with 1.2 and 22.6%, respectively, for children with single autoantibodies (P<0.001). Among the three examined autoantibodies, insulinoma-associated antigen-2 antibodies conferred the highest risk. CONCLUSIONS: The diabetes risk in schoolchildren with multiple autoantibodies was similar to the risk reported in other studies for genetically preselected probands; thus, a combined autoantibody-based screening could effectively identify at-risk individuals from the general population for future intervention trials.

High density FTA plates serve as efficient long-term sample storage for HLA genotyping.

Storage of dried blood spots (DBS) on high-density FTA(®) plates could constitute an appealing alternative to frozen storage. However, it remains controversial whether DBS are suitable for high-resolution sequencing of human leukocyte antigen (HLA) alleles. Therefore, we extracted DNA from DBS that had been stored for up to 4 years, using six different methods. We identified those extraction methods that recovered sufficient high-quality DNA for reliable high-resolution HLA sequencing. Further, we confirmed that frozen whole blood samples that had been stored for several years can be transferred to filter paper without compromising HLA genotyping upon extraction. Concluding, DNA derived from high-density FTA(®) plates is suitable for high-resolution HLA sequencing, provided that appropriate extraction protocols are employed.

IDO1 and IDO2 gene expression analysis by quantitative polymerase chain reaction.

Immunomodulatory properties of IDO1 relate to tryptophan catabolism. The degradation of tryptophan by IDO1 leads to suppression of T cell responses. Recently, another enzyme with IDO-like activity, indoleamine 2,3-dioxygenase-like-protein 1 (INDOL1, IDO2), has been described in both mice and humans. In order to study the gene expression of IDO1 and IDO2, we have developed a quantitative PCR (qPCR) assay. In an exploratory application to the study of the differential expression of IDO1 and IDO2 by professional antigen-presenting cells and MSCs (mesenchymal stromal cells) under the influence of interferon-γ (IFN-γ) and T-lymphocyte conditioned media (TCM), substantial differences were observed. IDO expression measured by qPCR was valid and reliable in the cell types investigated. Further studies are needed to delineate factors driving IDO expression in MSCs.

A multi-site study using high-resolution HLA genotyping by next generation sequencing.

The high degree of polymorphism at human leukocyte antigen (HLA) class I and class II loci makes high-resolution HLA typing challenging. Current typing methods, including Sanger sequencing, yield ambiguous typing results because of incomplete genomic coverage and inability to set phase for HLA allele determination. The 454 Life Sciences Genome Sequencer (GS FLX) next generation sequencing system coupled with conexio atf software can provide very high-resolution HLA genotyping. High-throughput genotyping can be achieved by use of primers with multiplex identifier (MID) tags to allow pooling of the amplicons generated from different individuals prior to sequencing. We have conducted a double-blind study in which eight laboratory sites performed amplicon sequencing using GS FLX standard chemistry and genotyped the same 20 samples for HLA-A, -B, -C, DPB1, DQA1, DQB1, DRB1, DRB3, DRB4, and DRB5 (DRB3/4/5) in a single sequencing run. The average sequence read length was 250 base pairs and the average number of sequence reads per amplicon was 672, providing confidence in the allele assignments. Of the 1280 genotypes considered, assignment was possible in 95% of the cases. Failure to assign genotypes was the result of researcher procedural error or the presence of a novel allele rather than a failure of sequencing technology. Concordance with known genotypes, in cases where assignment was possible, ranged from 95.3% to 99.4% for the eight sites, with overall concordance of 97.2%. We conclude that clonal pyrosequencing using the GS FLX platform and CONEXIO ATF software allows reliable identification of HLA genotypes at high resolution.

Improved KIR gene and HLA-C KIR ligand sequence-specific primer polymerase chain reaction genotyping using whole genome amplification.

Molecular analysis of genetic polymorphism for clinical or research purposes may be compromised by genomic DNA of limited quality and quantity. In this study, we have successfully tested the feasibility of using whole genome amplification (WGA) to allow genotyping for killer cell immunoglobulin-like receptor (KIR) genes and human leucocyte antigen (HLA)-C KIR ligand dimorphism on HLA-C. WGA was achieved by multiple displacement amplification (MDA) using bacteriophage phi29 polymerase. For KIR genotyping, a revised sequence-specific primer polymerase chain reaction protocol consisting of 23 primer pairs was used avoiding hitherto undetected cross-priming involving KIR2DL1, KIR2DS1, KIR3DL1 and KIR3DS1 alleles. Similarly, MDA-amplified genomic DNA was analyzed for the detection of the HLA-C KIR ligand groups C1 and C2, based on the amino acid K/N dimorphism in position 80.

Regional differences in HLA antigen and haplotype frequency distributions in Germany and their relevance to the optimization of hematopoietic stem cell donor recruitment.

We analyzed regional differences in human leukocyte antigen (HLA)-A, -B, and -DR antigen and haplotype frequencies based on a sample of approximately 320,000 German donors in order to identify regions that are especially suited for ongoing stem cell donor recruitment. Geographic partitioning was carried out by postal code regions. Analysis of genetic distances suggests the existence of three regional clusters in South (regions 6-9), East (0-1), and Northwest (2-5) Germany. The southern cluster shows most favorable characteristics with respect to haplotypic and phenotypic diversity and the occurrence of rare HLA antigens. The opposite behavior is shown by regions 2-4 of the northwestern cluster. As a result of lower HLA diversity, completeness of a regional donor file in region 4 with 100,000 donors would be higher than that of a file in region 7 with 170,000 donors. This fact shows the relevance of regional HLA differences for practical donor registry planning. Results such as those presented in this work can be used to diminish the problem of decreasing marginal benefit of donor recruitment, as more than 13 million donors are registered worldwide today.

Cardiac magnetic resonance imaging for myocarditis and nonischemic cardiomyopathies.

Cardiovascular magnetic resonance (CMR) is the gold standard for quantification of ventricular size, mass and function. Moreover, CMR can differentiate transient and permanent tissue damage. Therefore CMR is clinically useful to differentiate acute myocarditis from infarction. Various CMR markers for acute myocardial inflammation are reviewed. Moreover CMR can differentiate tissue changes in various nonischemic cardiomyopathies. This has a major clinical impact for diagnosis and risk stratification in these patients. Serial monitoring is feasible due to high reproducibility and the lack of radiation. The strengths and pitfalls in CMR imaging of nonischemic cardiomyopathies are reviewed in detail including an overview of the current literature.

Higher frequencies of HLA DQB1*05:01 and anti-glycosphingolipid antibodies in a cluster of severe Guillain-Barré syndrome.

Few regional and seasonal Guillain-Barré syndrome (GBS) clusters have been reported so far. It is unknown whether patients suffering from sporadic GBS differ from GBS clusters with respect to clinical and paraclinical parameters, HLA association and antibody response to glycosphingolipids and Campylobacter jejuni (Cj). We examined 40 consecutive patients with GBS from the greater Munich area in Germany with 14 of those admitted within a period of 3 months in fall 2010 defining a cluster of GBS. Sequencing-based HLA typing of the HLA genes DRB1, DQB1, and DPB1 was performed, and ELISA for anti-glycosphingolipid antibodies was carried out. Clinical and paraclinical findings (Cj seroreactivity, cerebrospinal fluid parameters, and electrophysiology) were obtained and analyzed. GBS cluster patients were characterized by a more severe clinical phenotype with more patients requiring mechanical ventilation and higher frequencies of autoantibodies against sulfatide, GalC and certain ganglioside epitopes (54 %) as compared to sporadic GBS cases (13 %, p = 0.017). Cj seropositivity tended to be higher within GBS cluster patients (69 %) as compared to sporadic cases (46 %, p = 0.155). We noted higher frequencies of HLA class II allele DQB1*05:01 in the cluster cohort (23 %) as compared to sporadic GBS patients (3 %, p = 0.019). Cluster of severe GBS was defined by higher frequencies of autoantibodies against glycosphingolipids. HLA class II allele DQB1*05:01 might contribute to clinical worsening in the cluster patients.

Decreased alloreactivity after vaccination against hepatitis B.

The beneficial effect of blood transfusions on renal allografts disappeared at about the same time when hepatitis B vaccination was introduced in dialysis patients. To determine possible immunosuppressive effects of hepatitis B vaccination, we studied alloreactivity during the course of immunization. Fourteen healthy subjects without serological evidence of hepatitis B were routinely immunized against hepatitis B surface antigen. Plasma and mononuclear cells were isolated and frozen before immunization and after vaccination, respectively. Mean alloreactivity measured by [3H]thymidine uptake decreased from 64,772 cpm before immunization to 40,213 cpm after the third immunization. In crossover experiments, cellular modulation and plasma-dependent modulation of alloreactivity were observed. The immunosuppressive effect of plasma taken 4 weeks after the third vaccination correlated (r = 0.9) highly significantly (P < 0.005) with the anti-hepatitis B surface antigen antibody titer. Taken together, our data strongly suggest that hepatitis B vaccination is capable of reducing allogenic reactivity.

Microchimerism after liver transplantation: prevalence and methodological aspects of detection.

BACKGROUND: Microchimerism after liver transplantation is a readily observed phenomenon. The immunological implications, however, remain unclear. Moreover, methodological approaches and their detection limits in the study of allogeneic microchimerism have not been studied in detail. METHODS: Therefore, the aim of this study was to evaluate the single-step and nested formats of the polymerase chain reaction/sequence-specific priming (PCR-SSP) approach under standardized conditions. For that purpose, a panel of recombinant plasmid clones was generated by PCR cloning. The panel contained the allelic sequences of the second exon of DRB1 covering all DR specificities on a low-resolution level. Using this panel, limiting dilution assays for various DR sequences in the presence and absence of competitor DNA were carried out to determine the minimal number of copies required for detection by single-step and nested PCR-SSP. Subsequently, 22 liver transplant recipients were analyzed in a retrospective study for the presence of allogeneic microchimerism by nested PCR-SSP. RESULTS: Although at least 10 copies of template DNA could be detected by nested PCR-SSP overall, single-step PCR-SSP was on average 10(2) to 10(3) times less sensitive. Upon the addition of human competitor DNA, the detection limits decreased on average by a factor of 10. In addition, sequence-specific differences in amplification efficiency could be appreciated. Using nested PCR-SSP, peripheral blood allogeneic microchimerism could be observed in 17 of 22 HLA-DR-mismatched liver recipients. Recombinants representing recipient DRB1 specificities were used to exclude false-positive results by lack of cross-reactivities of the donor-specific primers and to evaluate negative results due to sample-related reduced amplification efficiencies in microchimerism-negative recipients. In donor/recipient combinations that differed by at least one DR specificity, allogeneic microchimerism was seen in 87.5% of the cases. In five chimerism-negative cases, sample-related problems were detected in two cases. CONCLUSION: The optimization and standardization of the detection of genomic HLA sequences at low copy number may be greatly facilitated using a clonal reference system. Furthermore, a clonal reference system may be used to conduct cross-priming experiments to exclude false-positive results and may allow the determination of sample-specific detection limits for donor-derived HLA-DR specificities in chimerism-negative patients. Our evaluation of the PCR-SSP approach for the study of allogeneic microchimerism indicated that nested PCR-SSP provides the most sensitive format when HLA sequences are targeted. Yet, the detection sensitivity may vary between individual alleles and specificities. Allogeneic microchimerism in liver recipients can be observed in the majority of patients. However, the detection may be subject to the degree of mismatching, the HLA-DR alleles involved, and sample-related impaired PCR amplification efficiency.

Differential inhibitory effects of intravenous immunoglobulin preparations on HLA-alloantibodies in vitro.

BACKGROUND: Treatment of allosensitized patients with intravenously administered pooled immunoglobulin preparations (IVIG) may lead to a long-lasting reduction of anti-HLA alloantibody titers. An inhibitory response of IVIG preparations on lymphocytotoxicity is suggested to depend on IgG and to predict a successful reduction of anti-HLA alloantibodies upon the administration of high-dose IVIG in vivo. METHODS: In this study, we evaluated different IVIG preparations for their in vitro inhibitory capacity on lymphocytotoxicity and binding of anti-HLA alloantibodies to purified HLA antigens. For that purpose sera from 24 highly sensitized patients awaiting kidney transplantation and serological HLA testing reagents were used. Panel-reactive antibody (PRA) determinations using standard complement-dependent cytotoxicity testing and anti-HLA alloantibody determination by ELISA were carried out in the presence and absence of 50% (v/v) IVIG. RESULTS: The addition of IgG-containing IVIG preparations gave only a moderate inhibitory response judging from the average decrease of PRA levels (absolute DeltaPRA range: -2% to 16%), whereas the largest inhibition of lymphocytotoxicity was seen after the addition of IgM/IgA-containing IVIG preparations (absolute DeltaPRA range: 19% to 44%). For both IgG and IgM/IgA-containing IVIG preparations, the reduction of lymphocytotoxicity occurred in a dose-dependent fashion without a preference for particular anti-HLA class I antibody specificities. Significantly lower inhibitory effects on anti-HLA antibody reactivity were observed when the effects of IVIG preparations were monitored by ELISA (absolute DeltaPRA range: 7% to 22%). CONCLUSIONS: Our data suggest that the immunomodulatory capacity is largely caused by the IgM/IgA fraction of IVIG when analyzed by lymphocytotoxicity. The different effect on ELISA versus complement-dependent cytotoxicity testing suggests that interactions of IVIG with complement rather than anti-idiotypic antibodies may contribute to the inhibitory effects of IVIG in vitro.

Autoimmunity of diabetes.

Insulin-dependent diabetes mellitus is associated with a growing number of immune abnormalities. At the time of clinical onset, most patients developing the disease as children or young adults have autoantibodies reactive with islet beta cells. Current autoantibody markers for IDDM are not sufficient to predict the disease in the general population. Studies in first-degree relatives indicate the presence of a subclinical disease characterized by beta cell dysfunction, which may or may not progress to overt IDDM. Although IDDM is genetically linked to certain HLA-DQ class II molecules, it needs to be clarified whether these molecules determine the propensity to react to certain antigens, the failure to maintain tolerance, or the ability to produce disease-associated autoantibodies. Circumstantial evidence suggests that yet another gene outside the HLA complex on chromosome 6 is more important. The interaction with the environment needs to be clarified, and the etiologic role of viruses has not been substantiated. An underlying systemic autoimmune propensity may influence environmental insults and perpetuate islet beta cell destruction. Until these mechanisms are understood, clinicians should periodically check their patients with IDDM for other organ-specific as well as non--organ-specific autoimmune diseases. Our understanding of these phenomena is poor, which may explain why clinical trials with immunosuppressive agents have been of limited success. Further studies on the molecular biology of the immune response against islet beta cell-specific antigens are necessary for the development of both predictive tests and novel measures to prevent IDDM.

DQB1 promoter sequence variability and linkage in caucasoids.

Sequence variability in the upstream regulatory regions (URR) of HLA class II genes has been described as an additional mechanism of diversity in these polymorphic genes. For HLA-DQB1, 12 URR variants have been identified previously by sequence analysis of approx. 600 bp located immediately upstream of the first exon of the DQB1 gene. To investigate the distribution of these promoter alleles and their linkage with the structural portion of the DQB1 gene, a population-based study was carried out. Sequence information was utilized to develop 25 sequence-specific oligonucleotide probes to analyze enzymatically amplified locus-specific DNA. Supplemented with one sequence-specific primer pair to differentiate QBP1-6.2 from -6.3, all known 12 QBP1 alleles could be identified. Subsequently, 215 healthy, unrelated German controls were investigated for the distribution and linkage of DQB1 and QBP1 alleles. A total of 10 out of 12 known QBP1 alleles were observed. Since there was tight linkage between the promoter region and exon 2 of DQB1, the phenotype and genotype frequencies of the promoter alleles corresponded by and large to the frequencies observed for their linked DQB1 alleles. Exceptions were mainly seen for DQ5 and DQ6 haplotypes, as single DQB1 alleles could be linked to different, however, closely related QBP1 alleles and vice versa. Interestingly, for each DQB1 allele a single DQB1/QBP1 haplotype dominated (75.9 to 96.4%) the distribution. It is concluded that promoter and coding region variability are tightly linked by linkage disequilibrium. Exceptions are restricted to DQB1 DQ5 and DQ6 haplotypes. Since functional differences between different QBP1 alleles exist, the maintenance of haplotypic integrity may be of functional importance.

Gliadin antibodies in adult insulin-dependent diabetes--autoimmune and immunogenetic correlates.

Gliadin antibody (GA) tests used in screening for coeliac disease (CD) frequently yield positive GA results without accompanying CD in cases of diabetes mellitus type 1 (DM-1). To enlighten this phenomenon we screened 848 DM-1 patients for IgA- and IgG-GA. Subsequently, 16 out of 19 high titre GA patients (6 with CD) were compared with 37 low titre DM-1 patients matched for sex, age and disease duration, for autoimmune and immunogenetic markers. Chronic thyroiditis and thyroid peroxidase (TPO) antibody positivity were more frequent in the GA-positive than in the GA-negative sub-group (38 vs. 2.7%, p = 0.003, and 69 vs. 27%, p < 0.00, respectively). The tissue transglutaminase (tTg) IgA titres correlated with CD but not with GA. tTg IgG titres were lower in GA-positive individuals (p = 0.0012). GA-positivity correlated with a higher titre of factor XIII IgA antibodies (p < 0.001). GA-positive DM-I patients were characterised by a distinct immunogenetic profile; the risk of HLA DQB1*02 was lower among GA-positive patients than among GA-negatives (OR 0.4, preventive fraction 0.43). All CD patients were HLA DRB1*03-DQB1* 02-positive, but none of the five patients with normal biopsies. GA-positive patients instead had HLA DRB1*13 in 37.5% as compared to 8.6% in GA-negative (OR 6.4, etiologic fraction 0.32). Thus, the occurrence of positive GA in DM-1 is correlated to TPO antibody positivity, thyroiditis and factor XIII IgA antibodies, but inversely correlated to tTg IgG, and seems to be associated with another HLA haplotype than that previously found to be associated with CD.

Cyclosporine A sensitivity in vitro and P-glycoprotein expression in patients on dialysis and after kidney transplantation.

BACKGROUND: In allogeneic kidney transplantation the response to cyclosporine A (CsA) is important for graft outcome. Although CsA therapy is controlled by drug monitoring to ensure therapeutic CsA levels, the sensitivity to the effects of CsA varies among individuals. Since CsA is an antagonist of cytostatic drugs in P-glycoprotein (Pgp)-mediated transport, increased Pgp expression might contribute to an increased resistance to CsA. METHODS: The sensitivity of lymphocytes at three different concentrations of CsA was tested in a non-radioactive lymphocyte-transformation test and related to Pgp expression as determined by flow cytometry on mononuclear cells. Five groups, including healthy donors (CON; n = 25), patients on dialysis (DIAL; n = 25), patients before transplantation (PTX; n = 5) and after transplantation [short-term (ATX; n = 5) and long-term (LTX; n = 25)] were investigated. RESULTS: In LTX, the sensitivity to CsA at 400 and 1000 ng/ml was significantly different from CON and DIAL. Overall a higher sensitivity to CsA was seen in patients after transplantation. In ATX, sensitivity to CsA was significantly higher than in PTX at a concentration of 1000 ng/ml CsA. However, comparing all groups no significant changes in Pgp expression were noted. Analysing the relationship between CsA sensitivity and Pgp expression, no significant heterogeneity could be observed between the different groups. CONCLUSION: In conclusion, our data suggest that in vitro testing of CsA sensitivity prior transplantation and Pgp expression monitoring yield independent results and cannot substitute for each other as predictors of graft outcome. The differential role of each test for the evaluation of CsA sensitivity or resistance remains to be determined.

MR of the eye with retrobulbar anesthesia.

MR imaging with retrobulbar anesthesia was performed in eight patients with uveal melanoma. Injection of 2 mL prilocain hydrochloride in 2% epinephrin into the eye muscle cone resulted in improved image quality in seven patients, without side effects. Ocular MR imaging can be indicated to clarify indeterminate sonographic findings in cases of extrascleral growth or to exclude optic nerve invasion in patients with tumors located at the posterior pole of the globe.

The presence of HLA-DR B1 shared motif does not influence cyclophosphamide and methotrexate cytotoxicity in rheumatoid arthritis patients.

In the present study we investigated the relation between cyclophosphamide and methotrexate toxicity and the presence of HLA- DR B1 alleles in rheumatoid arthritis patients. Seventy-eight such patients (67 women and 11 men) were observed for 12 months. Eighteen were treated with intravenous cyclophosphamide, 28 with oral methotrexate, and 32 with intramuscular gold salts. The prevalence of this shared motif was higher in the study population than in the healthy controls. However, detailed observations did not demonstrate a relation between particular genotype and drug intolerance. Based on the obtained findings we concluded that HLA-DR B1 typing cannot affect cyclophosphamide or methotrexate tolerance in rheumatoid arthritis patients. However, taking into account the relatively small number of patients expressing single genotype, further studies are recommended.

[MRT of the eye: the normal anatomy and detection of the smallest lesions with a high-resolution surface coil]. / MRT des Auges: Normalanatomie und Nachweis kleinster Läsionen mit einer hochauflösenden Oberflächenspule.

PURPOSE: A new, high-resolution surface coil for MRI of the eye was evaluated with regard to practicability, image quality and sensitivity for small lesions. MATERIAL AND METHODS: 48 patients in whom a space-occupying lesion of the eye or orbit was suspected were examined (1.5 T tomograph, 5 cm surface coil, T1- and T2-weighted spin-echo sequences, the former before and after i.v. gadolinium DTPA). RESULTS: 45/48 patients tolerated MR with the high-resolution surface coil. No adverse effects were experienced by the patients. In 11/48 patients a space occupying lesion of the eye was detected (melanoma, 5; metastases, 2; haemorrhage, 1; malformation, hamartoma and scarring after melanoma, one each). The smallest detectable lesion had a thickness of < 1 mm. CONCLUSION: First experiences with the high-resolution surface coil indicate that this device is suited for detection of very small lesions of the eye.