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C M Zmijewski

Publications and source records attributed to C M Zmijewski.

At least 19 recordsLinked to original sources
PubMed1992

Positive crossmatches against mandatorily shared kidneys.

From October 1987 through February 1990 approximately 8.5% (29/341) of all donor kidneys shipped under the UNOS Mandatory Sharing Policy were denied to 27 intended recipients due to a positive final crossmatch [XM(+)]. The intended recipients included 18.5% hispanics and 7.4% blacks compared to 2.4% and 1.6%, respectively, for XM(-) recipients (1-3). Further, more were highly sensitized with 81% having a current PRA greater than 10% and 56% with a peak PRA greater than 80% compared to 65% and 14%, respectively, for XM(-) recipients. More importantly, 19/27 (70%) of the recipient candidates may have had irrelevant positive XMs. The XM(+) patients were classified into five categories defined by: I) autoantibodies; II) transfusions in the 2 weeks prior to the availability of the donor; III) the XM technique; IV) highly sensitized regraft candidates with current and peak PRAs greater than 85% and V) antibody to unreported MHC antigens. Of these, 70% may have been denied a transplant due to IgM autoantibodies or the use of XM techniques lacking extensive evaluation. The authors propose that all XM(+) mandatorily-shared kidneys be examined for IgM autoantibody and that kidneys not be denied to potential recipients due to IgM autoantibody. In addition, to minimize exclusions based on positive B-cell XMs, it is proposed that mandatorily-shared kidneys be shared on the basis of the DR subtypes, insofar as is currently practical.

Histocompatibility Testing↗
PubMed1992

Renal transplantation at the University of Pennsylvania Medical Center: an update of results in the cyclosporine era.

This chapter presents a summary of living-related, living-unrelated, and cadaver renal transplantation performed at the University of Pennsylvania Medical Center between January 1984 and October 1992. Over the past 9 years, 895 patients (557 males, 338 females, mean age 42 yrs) received 942 renal transplants; 599 patients received kidneys from cadaver donors (n = 627) and 296 patients received kidneys (n = 315) from living donors of all types. During this period, 151 patients were retransplanted, sometimes more than once (159 total retransplants, 124 secondary grafts, and 35 third or more transplants). An analysis of patient ant graft survival rates (calculated by actuarial methods) for different categories of transplant recipients was performed. Black recipients, as a racial subcategory, had the poorest graft outcome, especially when followed over the long term. Graft survival rates for Black recipients who were retransplanted with cadaver grafts were even worse and were noted to be similar to the diabetic population that received cadaver retransplants (66% vs 62% at 1 yr and 32% vs 25% at 5 yrs). Diabetic recipients of living-donor transplants had excellent graft survival results, similar to nondiabetic, living-donor recipients (patient survival rates 98% and 92% vs 97% and 92% at 1 and 5 yrs; graft survival rates 92% and 82% vs 92% and 82% at 1 and 5 yrs). HLA-identical recipients of first cadaver grafts demonstrated the best outcome in the entire cadaver series (graft survival rates 91% and 83% at 1 and 5 yrs, respectively). HLA-identical recipients of second or more cadaver grafts had poorer results than expected (50% graft survival at 1 yr) despite a 100% patient survival rate. HLA-identical recipients of living-related grafts had the best graft survival rates (96% at 1 yr and 94% at 5 yrs) and superior graft survival rates for retransplanted grafts as well (100% at 1 and 5 yrs). We conclude that in the last decade, patient and graft survival rates for cadaveric and living-donor renal transplants have improved dramatically relative to the results obtained in the pre-CsA era. Long-term graft survival in Black recipients remains lower than in other races, suggesting the need to analyze other factors to explain poorer graft survival in this recipient population. Results in diabetic recipients continue to be excellent at our center, encouraging the continuation of our aggressive approach to try to transplant diabetics as early as possible, particularly when a living donor is available.

Academic Medical Centers↗
PubMed1992

Demonstration of passenger leukocytes in a case of Epstein-Barr virus posttransplant lymphoproliferative disorder using restriction fragment length polymorphism analysis.

Lymphocytic populations of the posttransplant lymphoproliferative disorder in a completely matched renal allograft and a recipient's regional lymph node were examined, using restriction fragment length polymorphism analysis with probe YNH24 to the variable number tandem repeat D2S44. The donor's DNA was found in lymphocytes extracted from both the grafted kidney and the recipient's lymph node 26 days after engraftment. In both these organs, the results of in situ hybridization with a terminally biotin-labeled oligonucleotide probe to the Not I tandem repeat region of the Epstein-Barr virus (EBV) genome, as well as those of Southern blot hybridization to the EBV nuclear antigen region of the EBV genome, were positive. These findings confirmed the presence of the donor's lymphocytes ("passenger leukocytes") in the host nodal tissue in human renal transplantation and implicated EBV as playing a role in the development of posttransplant lymphoproliferative disorder. It is speculated that the EBV proliferative stimulus contributed to the recipient and the donor lymphocyte expansions. Alternatively, the proliferation of both lymphocyte populations could result from a mutual stimulation by minor histocompatibility or other antigens.

Cell Division↗
PubMed1991

Renal transplantation despite a positive antiglobulin crossmatch with and without prophylactic OKT3.

The antiglobulin crossmatch (AGXM) is a sensitive technique employed by many transplant centers to enhance detection of preformed antibody to donor antigens that may cause hyperacute rejection. However, positive AGXM may detect irrelevant or very low titers of anti-HLA antibody precluding transplantation in suitable recipients. To investigate the significance of a positive AGXM, cadaveric renal transplantation was carried out despite a weakly positive AGXM (defined as cell killing above background but not greater than 20%) in 48 recipients. In an initial group (n = 10), maintained on triple therapy (cyclosporine, azathioprine, and prednisone), accelerated acute rejection occurred in 4 recipients and 3 grafts were lost. A subsequent group (n = 38) was treated with a prophylactic course of OKT3 then triple therapy. There were no episodes of accelerated acute rejection (P less than 0.01) although clinical hyperacute rejection claimed one graft and the incidence of delayed graft function was high (75%). The prophylactic OKT3 group had a reduced incidence of acute rejection (0.5 versus 1.0) per recipient and the onset of first episodes was delayed (mean onset: 13 versus 35 days after transplantation). One year actuarial primary graft survival was 88% in the prophylactic OKT3 group as compared with only 50% in the initial group. The outcome in the positive AGXM group was similar to a concurrent group (n = 32) with a negative AGXM and immediate graft function. On the other hand, the subset of positive AGXM regraft recipients treated with prophylactic OKT3 fared poorly, with a 36% (4/11) incidence of primary nonfunction. In summary, a positive AGXM, as defined in this report, is not a contraindication to primary renal transplantation--in fact, the use of the AGXM will identify recipients that would benefit from prophylactic OKT3.

Adult↗
PubMed1989

Delineation of false-positive HIV antibody response in patients with renal failure and history of multiple transfusions.

Four patients with a history of multiple blood transfusions who awaited renal transplantation were tested for human immunodeficiency virus (HIV) infection and found to be positive on enzyme immunoassay (EIA) and negative on Western blot. None of these patients had any clinical evidence of HIV infection. Absorption of these patients' sera with B-lymphoblastoid cell lines (B-LCL) positive for the serologic specificities DR3, DR4 (Dw4, Dw10, Dw14), and DR5 resulted in EIAs that were negative for HIV. Treatment of the B-LCL with an anti-DR monoclonal antibody (L243) interfered with the absorption of the serum sample by B-LCL. This indicates that the initial false-positive EIA results may be due to HLA antibodies. Furthermore, it was shown that these HLA antibodies are not limited in specificity to the HLA type of the host cell used in the preparation of the EIA reagents, but can consist of other DR specificities.

Antibodies, Monoclonal↗
PubMed1989

Equine class II MHC antigens: identification of two sets of epitopes using anti-human monoclonal antibodies.

Six mouse and 13 rat monoclonal antibodies (mAb) recognizing HLA-DR, DQ and DP antigens were used for the detection of cell surface class II MHC antigens of equine lymphocytes. The monoclonal antibodies were tested against peripheral blood lymphocytes (PBL) from a panel of thoroughbred horses, using two-color fluorescence flow cytometry. Seven of these mAbs reacted with both surface immunoglobulin positive (sIg+) and surface immunoglobulin negative (sIg-) lymphocytes. sIg+ cells stained consistently brighter than sIg- cells. The fluorescence pattern did not vary from donor to donor for each of the mAbs tested, except for SFR1-MI.2, which reacted with a variable intensity with cells from 47 of 53 horses tested. Immunoprecipitation with mAb SFR1-MI.2 and analysis by two-dimensional electrophoresis demonstrated the presence of light and heavy chains equivalent to HLA class II alpha and beta chains. Antibody N297 (DQ specific), previously shown to react with an epitope expressed on human B cells but not on mitogen-induced T cells, reacted only with sIg+ cells in 42 of 53 horses tested. The lack of staining of horses sIg- cells with N297 may be due to a low or lack of expression of this determinant on these cells or to a weak cross-reactivity of this antibody with equine antigens.

Animals↗
PubMed1989

Subtypes of HLA-DQ and -DR defined by DQB1 and DRB1 RFLPs: allele frequencies in the general population and in insulin-dependent diabetes (IDDM) and multiple sclerosis patients.

We have used the HLA-DQB1 gene as a Southern hybridization probe with TaqI-digested genomic DNA in a study of 600 haplotypes from unrelated individuals and have characterized HLA-DQB1 RFLP patterns associated with the DR specificities DR1-DRw10 and DN1. For six of the specificities (DR2, 4, w6, 7, w8 and 9), we have also identified subtypes (multiple DQB1 band patterns). In a previous study (Cox et al. 1988), we identified RFLPs and subtypes with a DRB1 probe. Using the present results from DQB1 RFLPs to supplement those from DRB1 RFLPs, it was possible to discriminate among all the DR specificities with the exception of a minority of DR7 and DR9 subtypes. A comparison of DQB1 and DRB1 subtypes in the same subjects showed strong linkage disequilibrium for subtypes of some but not all DR specificities. We have also determined the allele frequencies of the DQB1 subtypes in controls and in patients with insulin-dependent diabetes mellitus (IDDM) or multiple sclerosis (MS). A consideration of subtypes in patients and controls indicated that for most DR specificities, neither IDDM nor MS was more strongly associated with any of the DQB1 subtypes than with the serologically defined DR antigens. The exceptions were the DQB1 patterns corresponding to the DQw3.2 subtype of DR4 and the rarer subtype of DR2, which were found in higher frequency in IDDM patients, as has been previously reported.

Alleles↗
PubMed1988

Evaluation of B-cell immunity in patients with pretransplant sensitization.

The influence of presensitization (blood transfusions) on B-cell immunity as reflected in the serum of two groups of candidates for cadaveric donor renal allografts was examined. The first group initially had a high level of panel-reactive antibody (PRA) greater than 72% but experienced a large decrease in PRA (greater than 70%) 6-34 months prior to transplantation. In contrast, the second group maintained a high PRA (100%) for up to 28 months after sensitization and before transplantation. Three blood Three blood samples from each patient, representing a maximum time span of 34 months, were analyzed. Levels of IgG, IgM isohemagglutinins, and antitetanus antibody were used as indicators of B-cell function. There were no significant differences between the individual values of a single patient with regard to each parameter. However, Group II patients had elevated values of total IgG relative to Group I patients. Total serum IgG-subclass levels (IgG1, IgG2, IgG3, IgG4) were measured and the relationship between a specific IgG subclass and the PRA activity was determined. IgG1 values in Group II were higher than those found for Group I. The other IgG subclasses were all within normal levels and were not significantly different between Group I and Group II. When IgG-subclass typing of PRA was performed, IgG1 accounted for most of the activity in both groups and a fall in PRA-specific IgG1 was associated with the reduced PRA observed in Group I. The data indicate that humoral immunity, as reflected by total and specific immunoglobulin levels, is intact in general in the two groups of presensitized renal allograft candidates examined and that any loss of PRA activity reflects a reduction in a specific immune response.

B-Lymphocytes↗
PubMed1988

Analysis of DR and DQ gene products of the DR4 haplotype in patients with IDDM: possible involvement of more than one locus.

Fifteen DR4-bearing haplotypes from twelve patients with insulin-dependent diabetes mellitus (IDDM) were analyzed serologically, cellularly, and biochemically. The HLA-Dw composition of these DR4-positive haplotypes was Dw4 (46%), Dw14 (22%), and Dw10 (33%). The biochemical analysis by two-dimensional electrophoresis (2D-PAGE) of the DR beta chains showed that each Dw specificity is characterized by a specific DR4 beta chain that appears to be identical in normal and diabetic individuals. Analysis of DQ beta chains in the DR4-bearing haplotypes revealed that certain Dw specificities such as Dw4 are characterized by the presence of either the DQw7 (formerly DQw3.1) or DQw8 (formerly DQw3.2) alleles, which generate the Dw4.1 or Dw4.2 subtypes, respectively. Others such as Dw14 and Dw10 are characterized by the presence of the DQw8 allele. In our sample of 12 patients the Dw4.2 (Dw4, DR4 beta I-4 DQw8) and Dw10 (Dw10, DR4 beta I-1, DQw8) subtypes were predominant. It is concluded that individual DR beta and DQ beta gene products from the DR4-bearing haplotype of IDDM patients are identical to those of normal control subjects and that Dw14 as well as Dw10 are involved in disease susceptibility. We suggest that disease susceptibility may be influenced by more than one locus within the HLA-D region.

Diabetes Mellitus, Type 1↗
PubMed1988

Increased sharing of maternal HLA haplotypes among children exposed to diphenylhydantoin during pregnancy.

During investigation of HLA types among children exposed to diphenylhydantoin (DPH) in utero, we found no evidence of a distortion in haplotype sharing among affected sib pairs. Unexpectedly, however, we found a marked increase in the proportion of all sib pairs (not just affected ones) sharing maternal haplotypes. Among 14 two child families, 12 shared the maternal haplotype (expected would be seven); among families with more than two children the distortion was also pronounced. This finding, if verified in future studies, could indicate that something in the mothers, whether DPH use during pregnancy, or some genetic factor associated with seizures, or some effect of the seizures themselves, may be leading to non-random segregation of HLA haplotypes in their offspring.

Child↗
PubMed1988

HLA-DR typing "at the DNA level": RFLPs and subtypes detected with a DR beta cDNA probe.

The HLA-DR beta gene, used as a hybridization probe, detects RFLPs that correlate with HLA-DR specificities. Using genomic DNA from more than 200 individuals, we have carried out a population study with a cDNA probe for the DR beta chain, which, under appropriate conditions, does not cross-hybridize with genes from other HLA-D subregions (e.g., DP and DQ). We first assessed the correspondence between serologically defined HLA-DR types and DNA patterns obtained after digestion with TaqI and found that DNA patterns allowed us to identify most specificities. Only two pairs of antigens are not distinguishable: with the DR beta probe alone we cannot distinguish DR3 from DRw6 or DR7 from DRw9. However, the correct assignment can always be made for the first pair by hybridizing the same digests with a DQ alpha or DQ beta probe. Thus DR typing from the DNA patterns is practical and accurate. We also looked for serologically undetectable subtypes. RFLPs revealed high-frequency subtypes for the specificities DR 2, 3, 5, w6, 7, and w9. Some of these are more accurately viewed as variant haplotypes, since the relevant variation is probably not at the DR beta locus that determines the serological specificities but rather at other closely linked and highly homologous DR beta loci such as DR beta-III. Nevertheless, the existence of variant haplotypes for so many specificities indicates a wealth of polymorphic variation beyond that detected serologically and provides more specific markers for studies of various diseases associated with HLA-DR specificities.

Asian People↗
PubMed1987

Carbohydrate differences in HLA-DR molecules synthesized by alveolar macrophages and blood monocytes.

Two-dimensional gel electrophoresis was used to compare immunoprecipitated, radiolabeled HLA-DR molecules synthesized by alveolar macrophages (AM) and blood monocytes (BM) of the same healthy, nonsmoking volunteers. No charge differences were noted by isoelectric focusing. Molecular weight analysis of HLA-DR from AM revealed a complex pattern of radioactive spots differing slightly in molecular weight. This pattern was apparent in both the alpha and the beta chains. In contrast, a simpler pattern without the slight molecular weight differences was noted in HLA-DR from BM. The differences were eliminated by labeling AM and BM in the presence of tunicamycin, a specific inhibitor of protein-carbohydrate linkages of the N-glycosidic type. Thus, it appears that neutral, N-linked carbohydrate moieties account for the differences in HLA-DR molecules between AM and BM. The differential glycosylation of HLA-DR molecules in AM and BM may relate to mononuclear phagocyte development as well as antigen-presenting function.

Carbohydrate Metabolism↗
PubMed1986

Cell surface antigen identification by a modified fluorescein immunosphere method.

Fluorescein immunospheres may be used in an indirect technic to label lymphocyte cell surface antigens. Wright's counter-staining allows simultaneous identification of fine morphology and surface antigen properties. Studies designed to determine methods for separating cells with bound immunospheres from free immunospheres revealed that removal of unbound immunospheres by flotation over cold protein solution creates excessive numbers of false negatives. Glutaraldehyde cross-linking of the primary and secondary antibodies linking immunospheres to the lymphocyte stabilizes the complex. This modification of the fluorescein immunosphere method compares favorably with flow cytometry.

Adult↗