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Biomedical subjects

G E Rodey

Publications and source records attributed to G E Rodey.

At least 37 records · Page 2Linked to original sources

Preoperative immunomodulation of renal allograft recipients by concomitant immunosuppression and donor-specific transfusions.

The induction of immunologic unresponsiveness to improve renal allograft survival was attempted in 113 patients by the pretransplant administration of donor-specific whole blood or buffy coat in conjunction with continuous Aza immunosuppression. All donor/recipient combinations were at least 1-haplotype disparate and 17 were 2-haplotype disparate. Presensitization, defined as a positive Amos or antiglobulin T cell CM or a positive high-titer (greater than or equal to 1:8) B cell CM was present in 10 patients and not present in 103 patients. Attempts at desensitization of the already sensitized group were uniformly unsuccessful. Treatment of the 103 nonpresensitized patients resulted in transient sensitization in 3 patients, permanent sensitization in 8, and no evidence of sensitization in 92. Ninety-one nonsensitized patients underwent renal transplantation from the specific blood donor, and only 5 have experienced renal allograft rejection loss during a mean follow-up period of 26 months (6 to 70 months). Fifty-four percent have never experienced a rejection episode. The allograft survival rate at 2 years (91%) and 5 years (89%) is significantly better (P less than .01) than our historical experience with 1-haplotype living-related transplants at 2 years (66%) and 5 years (64%). The low rate of sensitization (8%) has permitted almost all patients to undergo eventual renal transplantation from the specific blood donor. This and the low rate of rejection (5%) argues for a modification of the immunologic response rather than a selecting out process as the mechanism for improved allograft survival.

Azathioprine↗

Prediction of crossmatch outcome in highly sensitized dialysis patients based on the identification of serum HLA antibodies.

High levels of allosensitization (greater than 50%), which often occur in dialysis patients awaiting renal transplant, make donor selection difficult. Such patients may be included in elaborate protocols in which they are crossmatched with all available ABO compatible donors, or crossmatching may be deferred until a very-well-matched donor becomes available. The former approach of random crossmatching is costly and inefficient, while the latter approach may overlook crossmatch-compatible donors. We believe that the identification of antibodies present in highly reactive sera and the use of this information in donor selection would increase the frequency of crossmatch-negative donors for these patients. In this study eleven sera, reactive with 70% to 100% of a random cell panel, were obtained from multiply transfused dialysis patients. Sera were analyzed by standard (CDC) and antiglobulin augmented (AHG-CDC) lymphocytotoxicity, and by differential absorption with HLA-typed platelets. All sera contained only one or two antibodies directed against the high frequency public HLA epitopes, accounting for 85% to 100% of each serum's total reactivity. These characterized sera were crossmatched with 114 random normal donors. The frequency of negative crossmatches was 20.5%. However, if the serum antibody data had been used to preselect donors for crossmatch--that is, to exclude donors that were likely to be positive--the negative crossmatch frequency would have increased to 86.4%. The use of the serum analysis data in donor selection would have reduced the total number of required crossmatches by 78%. Serum analysis correctly predicted the outcome of 95.6% of crossmatches performed with an average of 3% false positives and 1.3% false negatives. This approach to donor selection reduces unnecessary crossmatching and increases the likelihood of finding crossmatch-compatible donors for highly reactive patients.

ABO Blood-Group System↗

Recalcified plasma as nutrient additive in mixed lymphocyte culture.

Animal or human blood protein is a costly but necessary additive to tissue culture. This supplemental protein is provided by the addition of pooled serum or heparinized plasma to standard tissue culture media. Many blood centers store CPDA-1 anticoagulated plasma, a form that does not provide optimal support of mixed lymphocyte culture (MLC). The optimal amount of CaCl2 (1 ml of 1 M CaCl2/100 g) added to citrate plasma and the use of glass vessels result in a completely clotted product that is comparable in MLC support to commercially available pooled human serum. Laboratories that have access to CPDA-1 plasma can replace the growing demand for serum with recalcified plasma without sacrificing quality.

Calcium↗

Histocompatibility leukocyte antigen and erythrocyte MNSs specificities in patients with meningitis or epiglottitis due to Haemophilus influenzae type b.

The frequencies of erythrocyte MNSs antigens and certain histocompatibility leukocyte antigen (HLA) specificities (HLA-A, HLA-B, and HLA-DR) were determined in white patients with meningitis or epiglottitis due to Haemophilus influenzae type b and in controls. The frequency of the erythrocyte MNSs genotype was significantly lower among patients with meningitis than among those with epiglottitis (P = 0.03); this observation confirms a trend observed previously. However, the frequencies of the HLA specificities did not differ significantly in the three groups studied; this result fails to confirm previous reports of disease associations with several HLA-A and HLA-B specificities. Although susceptibility to different clinical manifestations of haemophilus disease may be influenced by genetic factors, our studies indicate that the major loci conferring susceptibility are not in linkage disequilibrium with specificities in the major histocompatibility complex.

Antigens↗

Pretreatment of renal allograft recipients with immunosuppression and donor-specific blood.

The induction of immunologic unresponsiveness to improve renal allograft survival was attempted in 64 patients by the pretransplant administration of donor-specific whole blood or buffy coat in conjunction with continuous azathioprine immunosuppression. All donor/recipient combinations were at least one-haplotype-disparate. Presensitization, defined as a positive Amos or antiglobulin crossmatch or a high-titer (greater than 1:8) B-cell-positive crossmatch, was present in 6 patients and not present in 58 patients. Attempts at desensitization of the already sensitized group were uniformly unsuccessful. Treatment of the 58 nonpresensitized patients resulted in transient sensitization in 2 patients, permanent sensitization in 1 patient, and no evidence of sensitization in 55 patients. Fifty-three patients underwent renal transplantation from the specific blood donor, and only two have experienced renal allograft rejection loss during a mean follow-up period of 22 months (5-45 months); 57% have never experienced a rejection episode. The two-year renal allograft survival rate was 85%. This is significantly (P less than 0.01) better than our historical experience of 64% with one-haplotype living-related transplants. The low rate of sensitization (5%) has permitted almost all patients to undergo eventual renal transplantation from the specific blood donor. This and the low rate of rejection (4%) argues for a modification of the immunologic response, rather than a selecting-out process as the mechanism for improved allograft survival.

Adolescent↗

Antibodies directed against HLA-DR gene products exhibit the CYNAP phenomenon.

Two well characterized Eighth International Workshop sera, 8w1090 and 8w112 , described to have anti-DR3 and anti-DR5 activity, respectively, were tested by standard and antiglobulin augmented (AHG) complement dependent cytotoxicity (CDC) assays with 21 target cells. We demonstrate that both sera, in fact, have only one antibody (most likely anti-MT2), but have different CYNAP patterns. These observations are discussed with regard to a more complete analysis of antisera that detect gene products of the HLA-DR region.

Antibodies↗

HLA antigens in black and white patients with juvenile arthritis: associations with rheumatoid factor, hidden rheumatoid factor, antinuclear antibodies, and immune complex levels.

HLA typing for -A, -B, -C, -DR, and -MT antigens and simultaneous studies for the presence of 19S IgM rheumatoid factor (RF), hidden 19S IgM RF, antinuclear antibodies (ANA), and immune complexes (IC) were performed on 24 black and 80 white patients with juvenile arthritis (JA) of different onset types. HLA-DRW6 (p less than 0.05) was associated with pauciarticular onset and early onset pauciarticular black patients. HLA-DR4 was found in both blacks and whites with chronic disease (p less than 0.01) and with the presence of RF (p less than 0.05) and hidden RF (p less than 0.05). In the whites, HLA-DR5 (p less than 0.05) and DRW8 (p less than 0.001) were associated with pauciarticular onset and early onset pauciarticular patients. HLA- DRW8 was also associated with white JA patients with iridocyclitis (p less than 0.001) and black (p less than 0.01) and white patients (p less than 0.001) with the presence of ANA. HLA-MT2 was demonstrated in all 24 black patients (p less than 0.001) and in 54/80 white patients (p less than 0.001). HLA-MT2 was associated with black (p less than 0.01) and white (p less than 0.001) patients with early onset pauciarticular disease and the presence of iridocyclitis in white patients (p less than 0.001). The association of HLA antigens in black JA patients has not been reported before.

Antibodies, Antinuclear↗

Thymectomy-induced decrease in T gamma cells and OKT8+ cells in multiple sclerosis.

Studies were performed on lymphocytes from patients with multiple sclerosis before and after thymectomy (group I) and before and after thymectomy and azathioprine therapy (group II), and from matched control patients with multiple sclerosis, control patients with other neurological diseases, and healthy control subjects. Following treatment the percentage of T gamma cells in both group I and group II patients decreased from above the mean normal control levels to below this level; OKT8+ cell numbers in group I became lower than in any of the control groups; the percentage of concanavalin A-induced suppressor activity, which was initially normal, fell in group II and suggestively but not significantly in group I; and total blood lymphocytes in group I decreased from normal to below control levels. Other tests showed no significant changes with therapy. No significant difference in changes in clinical status were observed after one year in the treated patients compared with matched controls.

Adult↗

New approaches to donor crossmatching and successful transplantation of highly sensitized patients.

A class I HLA molecule may bear not only a private or unique determinant, but a shared, yet discrete, public epitope. These public determinants occur with a much higher frequency in the random donor population than the associated private determinants--and thus, are encountered more often in random donor blood transfusions and in renal transplantation. Sera from highly sensitized dialysis patients have been reported to contain a restricted number of antibodies to public determinants rather than a diverse array of antibodies directed against the private HLA-AB epitopes. As detailed in this report, comprehensive serum analysis of the public antibodies in highly sensitized transplant candidates has optimized identification of potential crossmatch-compatible donors and has avoided needless crossmatches. During the past two years, the incidence of renal transplantation from cadaveric donors to highly sensitized recipients has doubled at this institution. At 10-25 months following transplantation, 70% of these allografts are functioning. Private HLA class I antigen incompatibility was not a barometer for exclusion in the final donor crossmatch of these highly sensitized recipients. Furthermore, positive donor T cell crossmatches with sera obtained more than six months prior to transplantation may not represent an impediment to successful transplantation. We conclude that the approach of detailed antibody analysis can result in an improved outlook for successful transplantation of more dialysis patients who are highly sensitized to the class I HLA alloantigens.

Antibodies↗

Detection of two distinct public specificities on HLA-A28 bearing lymphocytes.

We have used the antiglobulin augmented cytotoxicity assay and platelet absorption-elution techniques to investigate crossreactivity among certain antigens coded by the HLA-A locus. These serologic and absorption studies demonstrated two supertypic determinants, distinct from private determinants, associated with HLA-A locus gene products. One determinant was present on HLA-A2, Aw23, Aw24, and A28 bearing lymphocytes; the other was found on HLA-A28, Aw33, Aw34, and A26 bearing lymphocytes. The second determinant was not associated with HLA-A25. Both supertypic determinants are associated with HLA-A28.

Antibody Specificity↗

In vitro response of human T cells to Pseudomonas aeruginosa.

Pseudomonas aeruginosa is a gram-negative bacillus that is a major cause of morbidity and mortality in immunosuppressed patients, burn patients, and patients with cystic fibrosis. Although immunity to these bacteria has been associated with serum antibody, more recent evidence suggests that T-cell-mediated immunity may also be important. To evaluate human T-cell responsiveness to these bacteria, the optimal conditions were determined for in vitro proliferation of human peripheral blood lymphocytes and T-lymphocytes to Fisher-Devlin immunotype 1 P. aeruginosa. The proliferative response of normal adult peripheral blood lymphocytes to heat-killed P. aeruginosa was studied in 34 subjects (range, 7,600 to 111,500 net cpm). Analysis of cell subpopulations indicated that T-lymphocytes are the major proliferating cells and that this response is enhanced by the presence of adherent cells. Data from fetal cord lymphocyte responses suggest that the proliferation seen in normal adult lymphocytes is induced by antigenic and not mitogenic stimulation.

Age Factors↗

In vitro immunization to KLH. II. Limiting dilution analysis of antigen-reactive cells in primary and secondary culture.

Limiting dilution analysis was used to estimate the frequency of human peripheral blood T lymphocytes that proliferate in response to in vitro immunization with keyhole limpet hemocyanin (KLH). Antigen-reactive cells (ARC) were estimated 9 days after primary immunization with KLH. The ARC frequency of lymphocytes from 12 subjects ranged from 1:23,800 to 1:52,631. Lymphocytes from five of these subjects were also primed for 12 days with KLH, rechallenged in secondary culture with fresh adherent cells and KLH, and assayed 4 days later. The ARC frequency increased to 1:1,123 to 1:7,247, indicating that T cell clones responsive to KLH had expanded during primary culture. In addition, we observed that the proliferative response of lymphocytes from 5 of the 12 subjects were inhibited at high cell concentrations. Depletion of OKT8+ T cells before culturing with KLH however did not alter the inhibitory effect of high concentrations of T cells.

Cells, Cultured↗

Demonstration of a third structurally distinct human Ia beta chain by two-dimensional gel electrophoresis.

Previous studies have indicated that HLA-DR homozygous cell lines express two Ia alpha and Ia beta chains that combine to form at least two Ia molecules. This report demonstrates by two-dimensional gel electrophoresis the existence of a third structurally distinct human Ia beta chain on DR2 and DR5 cell lines. This suggests that at least five separate genes control the expression of Ia molecules on HLA-DR homozygous cell lines.

B-Lymphocytes↗

Antigenic specificity of antibody reactive in the antiglobulin-augmented lymphocytotoxicity test.

The addition of an antihuman immunoglobulin (AHG) reagent to the basic complement-dependent cytotoxicity (CDC) test markedly increases the frequency of lymphocyte-reactive antibodies in many alloantisera. The extra reactivity has been previously identified as associated with alloantigens coded by the HLA complex, but definitive evidence establishing the antigenic specificity of the antibodies reactive by AHG-CDC has been lacking. We determined the nature and specificity of AHG-reactive alloantibodies through parallel testing (CDC +/- AHG) of a large battery of HLA alloantisera against panel cells composed of unrelated individuals and genotypic HLA-identical sibling pairs, and by means of differential platelet absorption and elution of alloantibody. We conclude that the AHG-CDC procedure, relative to "standard" CDC, detects subthreshold levels of alloantibody with specificity for the HLA-A, B, and C locus alloantigens. Most importantly, the AHGG-CDC technique consistently converts cytotoxicity-negative absorption-positive (CYNAP) HLA alloantibody to direct cytotoxic antibody, thus providing a more accurate assessment of the complete specificity of antibodies in complex alloantisera and patients' sera without having to resort to more cumbersome binding assays. These data should be of assistance in improving the characterization of HLA alloantisera used for serological and biochemical studies of the HLA molecules and in delineating the specificity of AHG-CDC antibody in clinical allotransplantation and single-donor platelet transfusion.

Absorption↗

The detection of two serologically distinct HLA-A28 specificities.

We describe a serum, 9045, that detects a subset of A28 bearing cells in a mixed population of American blacks, Caucasians of Jewish ancestry and non-Jewish Caucasians. The serum reacts preferentially with A28 positive cells from American Blacks and Jewish Caucasians and does not react with non-Jewish Caucasians. This new specificity, referred to as A28.2, is strongly associated with HLA-B14. In contrast, A28 positive but 9045 negative cells (referred to as A28.1) do not show this association. The A28-2 determinants appears to be antigenically similar to the A28.1 determinant, but distinct from the public antigenic determinants shared by A28, A2, A9 and by A28, Aw33, Aw34 and A26. Based upon this analysis, we conclude that HLA-A28, as defined by most A28 antisera, comprises at least two populations of molecules. The A28.2 form may have arisen in the Mediterranean basin region, whereas the A28.1 form seems to be more prevalent in non-Jewish Caucasians of Northern European ancestry.

Absorption↗