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J Grunewald

Publications and source records attributed to J Grunewald.

At least 73 records · Page 4Linked to original sources
PubMed1997

HLA-DR predicts the prognosis in Scandinavian patients with pulmonary sarcoidosis.

Although most patients with sarcoidosis have a good prognosis, a significant proportion runs a more severe and prolonged disease course. There is no marker to distinguish these subpopulations of patients, however. To investigate the relationship between HLA haplotype and clinical course, 122 Scandinavian patients with sarcoidosis were genomically typed for HLA-DR, -DQA1 and -DQB1 alleles using PCR amplification with sequence-specific primers. Control subjects were 250 healthy Swedish volunteers. Patients were carefully clinically monitored for up to 10 yr. We found that HLA-DR17(3) was overrepresented among sarcoidosis patients (33%) compared with control subjects (17%, p < 0.001). Ninety-one patients were followed for more than 2 yr and classified into chronic or nonchronic patients, according to disease outcome. Among the 34 patients with a nonchronic form of sarcoidosis, 65% were DR17(3)-positive (p < 10(-5) versus control subjects). On the other hand, DR14(6) and DR15(2) were significantly associated with chronic disease. Even in patients with clinical manifestations that are normally associated with good prognosis, HLA typing enabled a subgrouping into two categories with significantly different clinical courses. Therefore, HLA class II typing is a valuable tool in predicting the outcome of the disease in Scandinavian sarcoidosis patients.

Adult↗
PubMed1997

Lung and blood T-cell receptor repertoire in extrinsic allergic alveolitis.

Patients with extrinsic allergic alveolitis (EAA) have accumulations of T-lymphocytes in their lungs. CD8+ lung T-cells, in particular, have been implicated in the pathogenesis of EAA. The objective of the present study was to analyse the T-cell receptor (TCR) V alpha and V beta gene usage of CD4+ and CD8+ lung and peripheral blood lymphocytes (PBLs) before and after treatment. Twelve patients with clinical signs of extrinsic allergic alveolitis were studied at disease onset, and nine of the 12 were also studied after treatment and clinical recovery. Lung cells, obtained by bronchoalveolar lavage (BAL), and paired PBL samples were analysed by flow cytometry using a panel of anti-TCR V monoclonal antibodies. The changes in TCR V gene usage were most pronounced in BAL CD8+ cells, as compared to the BAL CD4+, PBL CD8+ and PBL CD4+ subsets. At disease onset, 10 of the 12 patients had lung restricted expansions of CD8+ T-cells using a particular V alpha or V beta gene segment, and 8 of the 12 patients had CD8+ T-cell expansions in PBL. For the patients in whom a follow-up was possible, a majority of the expansions in the lungs were normalized, whereas most of the expansions in PBL remained. An over-representation of human leucocyte antigen (HLA)-DR2 (15) was detected, particularly among patients with farmer's lung. An increased selected T-cell receptor V gene usage may follow specific interactions between T-cells and antigens. In extrinsic allergic alveolitis, we determined that such expansions occur most frequently in the lung CD8+ T-cells. Since most expansions of lung CD8+ T-cells normalized with clinical improvement, these are further implicated in the pathogenesis of extrinsic allergic alveolitis.

Acute Disease↗
PubMed1996

Enhanced prevalence of T cell receptor V beta 7 gene family expression in human intestine-associated T lymphocytes.

Relative levels of expression of T cell receptor variable (V) beta and joining (J) beta gene segments were determined in T cells derived from intestinal biopsies of healthy mucosal areas, mesenteric lymph nodes and peripheral blood of the same individuals. Samples taken from patients suffering from inflammatory (n = 8) and non-inflammatory (n = 8) bowel diseases were analyzed by semi-quantitative polymerase chain reaction-based methods. In the intestine, fewer (median = 3.5) V beta gene segments constituted more than 50% of the T cell receptor V beta repertoire compared to that of peripheral blood T cells (median = 7, P < 0.001). Interestingly, in all sixteen individuals studied, intestinal T lymphocytes (IL-T) expressed the V beta 7 gene family to a higher degree than did T cells in the paired peripheral blood and mesenteric lymph nodes (P < 0.001). T cell receptor J beta gene segment analyses of V beta 7+ T cells revealed no significant difference in oligoclonality rates between peripheral blood (4/16) and intestine (7/16) (P = 0.46). Hence, overexpression of intestinal TCR V beta 7 message does not seem to be due to oligoclonal expansions in the majority of the samples.

Adolescent↗
PubMed1996

T cell receptor (TCR) V gene segment use in HLA-typed Japanese healthy subjects.

The expression of 13 different alpha and beta V gene segments of the T cell receptor for antigen (TCR) was examined, using V gene-specific MoAbs, on human peripheral blood T lymphocytes from 32 healthy Japanese subjects. In addition, to examine associations between TCR V gene products and HLA alleles, the HLA class I and class II types of all subjects were serologically determined. The reactivities of the anti-TCR V-specific MoAbs were, with some significant exceptions, similar to those previously described in healthy Caucasian subjects. We found a non-random V gene usage as well as a statistically significant bias of the expression of eight V beta gene products towards the CD4+ subpopulation, and a significant skewness in the usage of V alpha 12 towards the CD8+ population. Some subjects showed increased reactivities (above 10%) of certain MoAbs, mainly in the CD8+ subpopulation. We found no distinct correlation between any certain HLA class I or II allele and TCR V gene usage in the CD8+ or CD4+ subpopulations, respectively. In conclusion, the pattern of anti-TCR V-specific MoAb reactivities found in CD4+ and CD8+ subsets of peripheral blood lymphocytes of healthy Japanese subjects was in general found to match that previously described in healthy Caucasian subjects.

Adult↗
PubMed1996

Different percentages of peripheral blood gamma delta + T cells in healthy individuals from different areas of the world.

The frequency of gamma delta + T cells in the peripheral blood of 26 Turkish, 24 Swedish, 35 Japanese and 14 "Asian' (non-Japanese) healthy blood donors and healthy volunteers were investigated by flow cytometry. In the Turkish group, 9.3% (median value) of the CD3+ peripheral blood T cells expressed the gamma delta T cell receptor. A similar level of gamma delta + T cells was found in the non-Japanese "Asian' healthy volunteers (9.2%), while significantly lower values were detected in the Swedish (4.2%) and Japanese (4.5%) groups. These dramatic differences in normally occurring gamma delta + T cells in different groups of healthy individuals were further reflected by a low incidence of > 10% gamma delta + T cells in the Swedish (0/24) and Japanese (6/35) groups compared to the Turkish (12/26) and "Asian' (5/14) groups. The described gamma delta + T cell differences between distinct ethnic groups are thus likely to be a consequence of environmental factors, but additional genetic influences cannot be ruled out. The present study demonstrates the potential importance of the ethnic origin and environmental history of subjects examined in studies of gamma delta + T cells-disease relations.

Adolescent↗
PubMed1995

Mechanisms of resistance to Onchocerca infection in blackflies.

In this article Peter Ham, Hans Hagen, Andrea Baxter and Jorg Grunewald focus on the susceptibility of blackflies to parasitic filarial infection (particularly Onchocera spp, most of the vectors of which belong to the genus Simulium). They outline what is known about, as well as speculating on, the various defence mechanisms of these insects. Investigations have involved the use of natural and surrogate vectors of bovine onchocerciasis as models for the human vector-parasite relationship.

Journal Article↗
PubMed1995

Analysis of gamma delta V region usage in normal and diseased human intestinal biopsies and peripheral blood by polymerase chain reaction (PCR) and flow cytometry.

The intestinal population of gamma delta T cell receptor (TCR)-bearing cells was characterized with regard to V delta and V gamma subtype expression. For this purpose, we utilized V gene-specific PCR of mRNA prepared from intestinal biopsies. Predominant expression of the V delta 1 subtype was demonstrated in the small intestine of patients with coeliac disease and in the inflamed colon of patients with inflammatory bowel diseases (IBD: ulcerative colitis and Crohn's disease) as well as in colon biopsies taken from macroscopically normal areas of colon. Although intestinal gamma delta T cells preferentially expressed V delta 1, other V delta transcripts could be detected, of which V delta 2 and V delta 5 were commonly expressed. Analysis of biopsies from mesenteric lymph nodes demonstrated a V delta repertoire similar to the mucosa. In peripheral blood on the other hand, high expression of both V delta 2 and V delta 1 was found. The predominant expression of V delta 1 transcripts in the intestinal mucosa of IBD patients correlated well with protein cell surface expression as analysed by flow cytometry using V delta 1- and V delta 2-specific antibodies. Selective expansion of gamma delta T cells could not be demonstrated within the inflamed mucosa as shown by mRNA analysis and flow cytometry. Instead, IBD patients demonstrated a decreased proportion of TCR gamma delta-carrying T cells in the inflamed mucosa compared with macroscopically normal area of colon. On the other hand, a significantly increased percentage of T cells bearing the gamma delta TCR was found in peripheral blood of patients with Crohn's disease compared with healthy individuals, indicating that local mucosal inflammation may influence the circulating gamma delta T cell population.

Base Sequence↗
PubMed1995

T cell receptor (TCR) V gene usage in patients with systemic necrotizing vasculitis.

Wegener's granulomatosis (WG) and polyarteritis nodosa (PAN) are systemic necrotizing vasculitides of unknown etiology. These disorders run a fatal course if untreated. T lymphocytes are implicated in the pathogenesis of WG, since they have been found to infiltrate affected organs, and sIL-2R correlates with disease activity. To elucidate further the role of T cells in necrotizing vasculitis, we have used a panel of 12 TCR V-specific MoAbs to investigate the number of cells expressing certain V alpha and V beta gene segments in the CD4+ and CD8+ subsets of altogether 11 patients with WG or PAN. In the group of patients, we found abnormal expansions of T cells using particular TCR V alpha or V beta gene products. These T cell expansions were more numerous, of a dramatically higher magnitude, and frequently more often found in the CD4 subset, compared with T cell expansions identified in healthy individuals. In long-term studies of the T cell expansions for up to 18 months, a heterogeneous pattern was revealed, with no obvious correlation to clinical features such as disease activity or treatment. Studies of TCR V gene usage in this group of patients may help in understanding the pathogenesis of necrotizing vasculitis, and in the identification of unknown antigens, and may open the possibility to a highly selective immunotherapy by targeting disease-mediating T cells.

Aged↗
PubMed1995

T-cell receptor J beta gene segment usage in immature and mature human thymocytes.

Immature double positive (DP, CD4+CD8+) and mature single positive (SP, CD4+CD8- and CD4-CD8+) human thymocytes from nine thymi were analysed for their complete patterns of relative TCR J beta multigene member usage in relation to six rearranged V beta family exons (V beta 5.1, 6.1-3, 8, 9, 12 and 18). Each sample tested contained mRNA transcripts corresponding to all potential V beta(D beta)J beta combinations. Individual J beta gene segments were expressed in a similar, highly non-random manner both in SP and DP thymocytes, irrespective of original genomic position of the individual associated V beta exon. In addition, ranges of family usage and frequency of individual over-representations of J beta gene segments, as determined in DP and SP thymocyte populations, displayed no significant differences. Upon comparison of DP and SP thymocytes, however, a discrepancy in one aspect of J beta gene utilization was established: decreasing J beta family 1/J beta family 2 ratios were determined to be positively correlated with increasing maturity of thymocytes, a condition further supported by data previously obtained from studies of PBL T cells. At the individual J beta gene level, the observed gradual modification of the relative family usage can largely be explained by a significant shift from a higher J beta 1.1/J beta 2.7 ratio in DP to a higher J beta 2.7/J beta 1.1 ratio in SP thymocytes. Altogether, the present results imply that selectional processes in the thymus appear to have only minor consequences on the distribution pattern of expressed J beta exons. Hence, the disproportionate pattern of TCR J beta gene usage seems to be established mainly at the recombinatorial level followed by minor adjustments during thymic and post-thymic events.

Cell Differentiation↗
PubMed1995

T-cell receptor V gene expression in HLA-typed Japanese patients with pulmonary sarcoidosis.

The clinical features of sarcoidosis vary in different ethnic groups, suggesting that different genetic or environmental backgrounds influence the disease. In Scandinavian sarcoidosis patients, we have previously described a correlation between lung-accumulated CD4+ T cells expressing the T-cell receptor (TCR) V alpha 2.3 gene segment and a particular HLA type (DR3[17],DQ2). For purposes of comparison, we have in this study investigated TCR V gene usage and gamma delta TCR expression in CD4+ and CD8+ T cells in bronchoalveolar lavage (BAL) fluid and peripheral blood in an ethnically distinct and homogenous group of individuals consisting of Japanese sarcoidosis patients and healthy controls. We used a panel of 13 monoclonal antibodies (Mab) specific for different TCR V genes, which altogether stained approximately 50% of the T cells, and triple staining techniques with flow cytometry. The patients and controls were also HLA-typed. Our results show a high degree of expression of gamma delta TCR in peripheral blood T cells of close to half of the patients. Expansions of T-cell subsets were readily detected in the CD8+ T-cell population, while a more homogenous staining pattern was found in the CD4+ T-cell population. These findings show the importance of ethnic origin and environment in discussions of TCR V gene usage.

Adult↗
PubMed1995

The in vitro culture of Onchocerca spp.: II. The excretory/secretory products of the first and third stage larvae of Onchocerca lienalis and O. ochengi.

The developing first and third larval stages of two bovine Onchocerca species were maintained in vitro in the presence of 35S-methionine, following their initial development in the vector species Simulium ornatum s.1. to characterise the expression and secretion of their metabolites. The first larval stages of O. lienalis and O. ochengi did not release any E/S products. In contrast the supernatants of the third stage larvae of both species contained a double band of 21 and 20 kDa for O. ochengi and 23 and 22 kDa bands for O. lienalis when kept at room temperature. A temperature shift to 37 degrees C led to the increased expression of the 23 kDa protein with the infective larvae of O. lienalis. The possible role of these molecules is discussed.

Animals↗
PubMed1995

The in vitro culture of Onchocerca spp.: I. Preliminary observations on the development of the second to the third stage larvae.

Second stage larvae of Onchocerca lienalis and O. gutturosa were induced to moult successfully to the third stage in vitro. Following development in their vectors Simulium ornatum s.l. and Culicoides nubeculosus the second stage larvae were kept in a cell free culture system. At least 25% of the second stage larvae of either Onchocerca species completed the moult successfully although no feeder layers had been used. In the absence of CO2 (5% in air) the number of the second stage larvae moulting successfully to the infective stage dropped to 6 and 9% respectively.

Animals↗
PubMed1995

Restricted usage of T cell receptor V alpha/J alpha gene segments with different nucleotide but identical amino acid sequences in HLA-DR3+ sarcoidosis patients.

BACKGROUND: Sarcoidosis is a granulomatous disease characterized by the accumulation of activated T cells in the lungs. We previously showed that sarcoidosis patients expressing the HLA haplotype DR3(17),DQ2 had increased numbers of lung CD4+ T cells using the T cell receptor (TCR) variable region (V) alpha 2.3 gene segment product. In the present study, the composition of both the TCR alpha- and beta-chains of the expanded CD4+ lung T cells from four DR3(17),DQ2+ sarcoidosis patients was examined. MATERIALS AND METHODS: TCR alpha-chains were analyzed by cDNA cloning and nucleotide sequencing. TCR beta-chains were analyzed for V beta usage by flow cytometry using TCR V-specific monoclonal antibodies or by the polymerase chain reaction (PCR) using V beta- and C beta-specific primers. J beta usage was analyzed by Southern blotting of PCR products and subsequent hybridization with radiolabeled J beta-specific probes. RESULTS: Evidence of biased J alpha gene segment usage by the alpha-chains of V alpha 2.3+ CD4+ lung T cells was found in four out of four patients. Both different alpha-chain nucleotide sequences coding for identical amino acid sequences and a number of identically repeated alpha-chain sequences were identified. In contrast, the TCR beta-chains of FACS-sorted V alpha 2.3+ CD4+ lung T cells were found, with one exception, to have a nonrestricted TCR V beta usage. CONCLUSIONS: The finding of V alpha 2.3+ CD4+ lung T cells with identical TCR alpha-chain amino acid sequences but with different nucleotide sequences strongly suggests that different T cell clones have been selected to interact with a specific sarcoidosis associated antigen(s). The identification of T cells with restricted TCR usage, which may play an important role in the development of sarcoidosis, and the possibility of selectively manipulating these cells should have important implications for the treatment of the disease.

Adult↗
PubMed1994

T-cell receptor variable region gene usage by CD4+ and CD8+ T cells in bronchoalveolar lavage fluid and peripheral blood of sarcoidosis patients.

Sarcoidosis is a chronic noncaseating granulomatous disease of unknown etiology. An accumulation of CD4+ T cells in the alveolar space of the lungs is a characteristic feature of the disease. We have in this study analyzed T-cell receptor (TCR) variable region (V) gene usage by CD4+ and CD8+ lung and peripheral blood T cells of 29 sarcoidosis patients and 15 control subjects. In the patient group, we found a 100% positive correlation between TCR V alpha 2.3+ CD4+ lung T-cell expansions and the expression of the HLA-DR3(17),DQ2 haplotype. The remaining TCR V alpha/V beta gene products analyzed in this study--V alpha 12, V beta 2, V beta 3, V beta 5.1, V beta 5.2/5.3, V beta 5.3, V beta 6.7, V beta 8.1, and V beta 12--were in general normally expressed by CD4+ T cells, although some of them were used to a significantly higher or lower degree by lung T cells compared to peripheral blood T cells. We also performed repeated TCR V gene analyses on some HLA-DR3+ patients and found an association between the ratio bronchoalveolar lavage fluid/peripheral blood V alpha 2.3+ CD4+ T cells and clinical signs of disease activity. Finally, when analyzing TCR V gene usage by CD8+ bronchoalveolar lavage fluid and peripheral blood T cells, a normal V alpha 2.3 usage was found in all cases, but lung-restricted T-cell expansions using other TCR V gene segment products were identified.

Adult↗