Search PubMed⌕ Search

Biomedical subjects

V Lenhard

Publications and source records attributed to V Lenhard.

At least 55 records · Page 3Linked to original sources
PubMed1979

HLA B27 and defects in the T-cell system in Whipple's disease.

The cellular immune system was tested in nine patients with Whipples' disease. Three patients had active disease, and six had been in remission for up to 10 years. Intradermal delayed hypersensitivity reactions to candidin, trichophytin, tuberculin and varidase, T-cell counts as determined by E-rosettes, allogeneic stimulation of lymphocytes in the mixed lymphocyte culture, and mitogenic activation of lymphocytes by concanavalin A, phytohaemagglutinin and by pokeweed mitogen, were tested in the patients and compared with control subjects. HLA typing was performed in all patients. The reaction to tuberculin and varidase, the T-cell counts and the activation of lymphocytes by concanavalin A were significantly reduced in patients with active disease and in patients during remission. The reaction to candidin and trichophytin was poor even in the controls. The mean results of the mixed lymphocyte culture, phytohaemagglutinin, and pokeweed mitogen activation tests were not significantly different from the controls. In patients with active disease the mixed lymphocyte culture reaction and the T-cell counts were less than in patients in remission. The results suggest a persistent defect of T-cells in patients with Whipple's disease, a defect that is more severe in patients with active disease. The finding of HLA B27 in four of thenine patients supports the hypothesis of primary rather than secondary impairment of the cellular immune system in Whipple's disease.

Adult↗
PubMed1979

Separation of the gonadotropic activity of crude choriogonadotropin from the inhibitory effect on lymphocyte transformation.

The effect of choriogonadotropin of different purities on the transformation of peripheral human lymphocytes was studied. Various crude hormone batches inhibited lymphocyte transformation in a dose-dependent manner, both in the mixed lymphocyte reaction and in the phytohemagglutinin-induced stimulation. The inhibitory activity, however, was found not to be correlated with the gonadotropic activity of the crude hormone batches (2660-4300 IU/mg). Choriogonadotropin (13 000 IU/mg), which was purified in 3 steps, showed no inhibitory effect except at high doses (greater than 5000 IU/ml final dilution). More detailed investigations provided evidence that in the first step of the choriogonadotropin purification procedure (batch adsorption of crude choriogonadotropin on SP-Sephadex C-50), the inhibitory activity can be enriched in a fraction (Fract. I) which displays a very low gonadotropic activity (less than 500 IU/mg). A further separation of Fract. I was achieved by isoelectric focusing as well as by chromatography on DEAE-Sephadex A-25. By these means, the inhibitory potency could be enriched more than 100-fold. The substances which display inhibition of DNA synthesis in lymphocytes were proven to act in a nontoxic way. A preliminary characterization of the strongly inhibiting substances which show a dose-dependent suppression of lymphocyte transformation by about 99%, showed that this effect is probably exerted via non-dialysable sialoglycoproteins. By a fourth purification step entailing a chromatography of purified choriogonadotropin (13 000 IU/mg) on SP-Sephadex C-50, a highly purified choriogonadotropin (14000 IU/mg) could be obtained which showed no inhibitory effect on lymphocyte transformation (in both mixed lymphocyte reaction and in phytohemagglutinin-induced stimulation) up to a dose of 43 000 IU/ml. The components which were removed from choriogonadotropin in this step seem to be immunologically identical with the strongly inhibiting substances isolated by isoelectric focusing. These investigations demonstrate that biologically active, highly purified choriogonadotropin is unable to inhibit lymphocyte transformation. The inhibitory activity of crude hormone can be enriched in choriogonadotropin-free fractions. Therefore, it is concluded that the inhibitory activity of crude hormone is not a property of choriogonadotropin itself.

Chorionic Gonadotropin↗
PubMed1979

The Lewis antigen system and its relevance for clinical transplantation.

The influence of the Lewis blood group system on transplant survival was studied retrospectively in 161 kidney transplantations. Le (a-b+) recipients had significantly higher graft survival rates than Le (a+b-) or Le (a-b-) recipients. From the known distribution of the Lewis blood groups among the European population, a high percentage of Lewis-compatible transplants would be expected among Le (a-b+) recipients in contrast to the Le (a+b-) and Le (a-b-) recipients. Other factors which are known to influence transplant prognosis such as HLA-match between donor and recipient, ischemic time of the transplants and pretransplant blood transfusions did not differ significantly in any of the three groups studied. Our data again suggest the relevance of the Lewis blood group system for clinical kidney transplantation. The findings should be confirmed by prospective typing of donor and recipient for Lewis antigens.

Graft Survival↗
PubMed1979

Influence of the Lewis blood group system on clinical kidney transplantation.

The different Lewis phenotypes were determined retrospectively in 201 kidney transplant recipients. Transplant survival rates in Lewis compatible recipients were significantly higher (p less than 0.0005) than in Lewis incompatible recipients. The improvement of transplant prognosis by matching for Lewis antigens was confirmed by a prospective study comprising 55 donor/recipient combinations. HLA matching had little benefit on transplant survival whereas survival rates are strikingly increased by Lewis compatibility. In the Lewis compatible but HLA mismatched group, graft survival was definitely higher than in the HLA matched but Lewis mismatched group. Our data indicate that Lewis antigens play an important role in transplant prognosis. Compatibility in the Lewis system should therefore be considered when recipients are selected.

ABO Blood-Group System↗
PubMed1978

The HLA system and leprosy in Thailand.

To investigate immunogenetics of leprosy, 205 leprosy patients (26 with tuberculoid, 57 with borderline-tuberculoid, 21 with borderline, 31 with borderline-lepromatous, and 70 with lepromatous leprosy) have been typed for HLA antigens, and compared with 183 healthy controls from the same region (Northern Thailand). There was no significant difference between the overall group of leprosy patients or the three borderline classes and the controls. The two polar forms, tuberculoid and lepromatous leprosy, however, showed significant associations: HLA-A2 is decreased and HLA-Bw17 is increased in tuberculoid leprosy; HLA-B7 is increased in lepromatous leprosy. When both polar forms are compared with each other, HLA-A2 is significantly higher, HLA-Bw40 lower in patients with lepromatous than in those with tuberculoid leprosy. The results are discussed with respect to the different immune responsiveness in the two polar forms of leprosy.

Female↗
PubMed1978

HLA antigen, gene, and haplotype frequencies in Thailand.

Antigen, gene, and haplotype frequencies as well as phenotype distribution of the HLA system were studied in a series of 213 individuals in northern Thailand. The series consisted of 160 northern Thais, 23 Thai individuals from various other regions of Thailand, and 25 persons of Chinese origin. Most frequently found were the alleles HLA-A11 and HLA-Bw40 and the haplotype HLA-A2,B-. Phenotype distribution followed a Hardy-Weinberg expectation. Significant differences were found especially between our results for the alleles of locus B and the results of a series from Bangkok reported by Chiewsilp and Chanarat (1976).

Adolescent↗
PubMed1978

Presensitization of potential kidney recipients detected by cell kinetic studies in the pooled mixed lymphocyte reaction.

An accelerated response in the pooled mixed lymphocyte reaction (PMLR) and/or the existence of cytotoxic antibodies indicates presensitization of potential kidney recipients. The absence of cytotoxic antibodies does not exclude presensitization, which can be demonstrated by a premature response in the PMLR. However, transfusions may also lead to impaired proliferation. In some patients, blood transfusions induce blocking activities. The possible mechanisms of this phenomenon are discussed. Measuring the immune response by cell kinetic studies with the PMLR gives further information on the immune state of potential kidney recipients.

Cytotoxicity, Immunologic↗
PubMed1978

Identification of I/i, Pr1-3 and Gd antigens in the human kidney: possible relevance to hyperacute graft rejection induced by cold agglutinins.

Human cold agglutinins (CA) with I/i, Pr1--3 and Gd specificities were tested for reactivity against kidney tissue by immunofluorescent techniques. I/i antigens were found on the epithelia of the Henle's loops and distal tubules. Pr1--3 antigens were demonstrated on the glomerular capillaries. Gd antigens were localized on the endothelia of the glomerular and peritubular capillaries as well as in the kidney interstitium. From these results, it is suggested that hyperacute rejection of renal transplants in recipients with high-titre CA may not only be caused by intravascular erythrocyte agglutination but also by direct cytotoxic damage of the transplant. Since CA occur frequently in potential kidney recipients, pre-operative determinations of CA in these patients should be recommended.

Adult↗
PubMed1978

Long-term results in children following dialysis and renal transplantation.

Since 1966, 93 children in end-stage renal disease, aged between 5 and 16 years were treated by a combined programme of dialysis and transplantation. In 91 patients treatment of uraemia was started either as hospital or home haemodialysis, until now covering more than 90 dialysis years. Forty-one children were transplanted. Twenty children died during dialysis treatment, 7 after renal transplantation. Sixty-six children are currently alive, 25 with a functioning graft, 28 are treated by hospital dialysis, 13 by home haemodialysis. Eighty-three per cent of the patients on hospital dialysis are classified in rehabilitation category 2 according to the EDTA categories, and all children on home dialysis and those with functioning grafts, category 1.

Adolescent↗
PubMed1978

Chemotactic activity of lectins in vitro.

The effects of concanavalin A (Con A) and leucoagglutinin (LA) on the locomotor response of phagocytes have been studied in vitro. At concentrations of 1 to 4 microgram/mol, Con A and LA induced maximal chemokinesis and chemotaxis of monocytes, macrophages and, to a lesser degree, also of neutrophils. The lectin-induced locomotion was accompanied by membrane alterations and metabolic changes, as shown by an increase of the 3H-uridine uptake and a rise of the hexose monophosphate shunt activity. The chemotactic activity of Con A was inhibited by alpha-methyl mannoside (50 mM) or by pretreatment of the cells with trypsin. These data indicate that lectins such as Con A induce chemotaxis by a specific binding to receptors of the cell membrane. It is suggested that bivalent ligand binding is required as a signal to elicit chemotactic locomotion.

Agglutinins↗
PubMed1977

HLA-D typing with homozygous lymphoblastoid cell lines.

Lymphoblastoid cell lines (LCL) was established from peripheral blood lymphocytes (PBL) of 2 HLA-DW 3 homozygous siblings. HLA-D typing was performed with the homozygous LCL and PBL in a group of 51 unrelated individuals selected according to their HLA-A,B locus antigens. All the individuals who were typed positive for DW3 with PBL typing cells could also be typed positive with the LCL typing cells. Both homozygous LCL behave very similarly in the tested population. These experiments showed that the same HLA-D determinants were represented both on LCL and PBL cells and that LCL derived from MLC homozygous donors can be used for HLA-D typing.

Cell Line↗