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N Reinsmoen

Publications and source records attributed to N Reinsmoen.

At least 19 recordsLinked to original sources
PubMed1996

Does re-exposure to mismatched HLA antigens decrease renal re-transplant allograft survival?

UNLABELLED: We analyzed 420 kidney retransplants at the University of Minnesota, 87 of which did and 333 which did not share HLA mismatches with the previous transplant. There was no difference in outcome. We conclude that exceptions to routine HLA matching policies do not have to be made for kidney retransplants. OBJECTIVE: To determine if the kidney graft functional survival rate for retransplants is influenced by presence of HLA mismatches in common with the previous (failed) transplant. SUMMARY BACKGROUND DATA: Kidney retransplants have a lower function rate than primary grafts. An anamnestic response to HLA antigens shared with the previous donor could be one factor responsible, but reports in the literature are conflicting. METHODS: Of 420 kidney retransplants with HLA information done at the University of Minnesota, 87 shared > or = 1 HLA antigens specifically mismatched with the previous donor (63 cadaver and 24 living donor retransplants), while 333 did not (247 cadaver, 86 living donor). Patient and graft survival rates were calculated by life-table analysis for recipients with vs. without repeat mismatches, with the significance of differences determined by the Lee-Desu statistic. RESULTS: Patient and kidney graft retransplant survival rate curves were not significantly different (p > or = 0.41) for those exposed or not exposed to the same HLA mismatches as before. At 2 years, 70% vs. 61%, respectively, of cadaver grafts and 71% vs. 78%, respectively, of living donor grafts were functioning. CONCLUSIONS: The probability of a successful outcome with a kidney retransplant is no different for patients who do than for those who do not receive an organ sharing HLA mismatches with the previous donor. Exceptions to routine HLA matching policies do not need to be made for kidney retransplants.

Cadaver↗
PubMed1995

Weaning of immunosuppression in long-term liver transplant recipients.

Seventy-two long-surviving liver transplant recipients were evaluated prospectively, including a baseline allograft biopsy for weaning off of immunosuppression. Thirteen were removed from candidacy because of chronic rejection (n = 4), hepatitis (n = 2), patient anxiety (n = 5), or lack of cooperation by the local physician (n = 2). The other 59, aged 12-68 years, had stepwise drug weaning with weekly or biweekly monitoring of liver function tests. Their original diagnoses were PBC (n = 9), HCC (n = 1), Wilson's disease (n = 4), hepatitides (n = 15), Laennec's cirrhosis (n = 1), biliary atresia (n = 16), cystic fibrosis (n = 1), hemochromatosis (n = 1), hepatic trauma (n = 1), alpha-1-antitrypsin deficiency (n = 9), and secondary biliary cirrhosis (n = 1). Most of the patients had complications of long-term immunosuppression, of which the most significant were renal dysfunction (n = 8), squamous cell carcinoma (n = 2) or verruca vulgaris of skin (n = 9), osteoporosis and/or arthritis (n = 12), obesity (n = 3), hypertension (n = 11), and opportunistic infections (n = 2). When azathioprine was a third drug, it was stopped first. Otherwise, weaning began with prednisone, using the results of corticotropin stimulation testing as a guide. If adrenal insufficiency was diagnosed, patients reduced to < 5 mg/day prednisone were considered off of steroids. The baseline agents (azathioprine, cyclosporine, or FK506) were then gradually reduced in monthly decrements. Complete weaning was accomplished in 16 patients (27.1%) with 3-19 months drug-free follow-up, is progressing in 28 (47.4%), and failed in 15 (25.4%) without graft losses or demonstrable loss of graft function from the rejections. This and our previous experience with self-weaned and other patients off of immunosuppression indicate that a significant percentage of appropriately selected long-surviving liver recipients can unknowingly achieve drug-free graft acceptance. Such attempts should not be contemplated until 5-10 years posttransplantation and then only with careful case selection, close monitoring, and prompt reinstitution of immunosuppression when necessary.

Adolescent↗
PubMed1994

Early tolerance in pediatric liver allograft recipients.

The authors report on six pediatric liver transplant recipients for whom allograft tolerance occurred shortly after transplantation (ie, less than 1.5 years). All the patients had associated life-threatening viral complications. They are currently immunocompetent. The tolerant state may be related to the development of a TH2 cytokine pattern.

Female↗
PubMed1990

The molecular basis of alloreactivity.

The strength of the immune response to foreign histocompatibility molecules has long puzzled immunologists. In this article Robert Lechler and colleagues propose that (1) allorecognition is structurally heterogeneous and varies according to the responder and stimulator MHC types, (2) in closely related combinations the focus of the alloreactive T cell may be on epitopes of endogenous peptides that are displayed by stimulator but not by responder MHC molecules, seen in a 'self-restricted' manner, and (3) in more disparate combinations the alloresponse may be directed primarily against residues on the allogeneic MHC molecule itself.

Amino Acid Sequence↗
PubMed1983

Clonal analysis of T lymphocyte response to an isolated class I disparity.

A bulk primed lymphocyte reagent generated in a class II identical class I (HLA-B) disparate sibling combination demonstrated both cytotoxic [cell mediated lympholysis (CML)] and proliferative [i.e., primed LD (lymphocyte) typing (PLT)] reactivity associated with the class I antigen, Bw62. Cells from this bulk population were plated by limiting dilution and cloned by micromanipulation. Three functional groups of clones were isolated. Some clones derived were found specifically to proliferate to and lyse cells bearing the Bw62 antigen. Based on such reactivities, these clones were analogous to the class of antigen-driven, helper cell independent cytotoxic (HITc) clones previously reported from our laboratories. Other clones responded proliferatively to stimulation by Bw62 positive cells but were not cytotoxic, thus fitting characteristics of Th, although it will be necessary to test such clones for their ability to produce Interleukin 2 (IL-2). In addition, conventional cytotoxic clones which did not proliferative to, but did lyse cells bearing the Bw62 antigen were isolated. The results were consistent with the existence of both HITc and Tc mediated cytotoxicity generated against this isolated class I disparity.

Clone Cells↗
PubMed1983

Genetic and molecular analyses of lymphocyte-defined HLA-D region specificities.

Determinants encoded in the HLA-D region have been studied with both cellular (PLT) and molecular (SDS-IEF) methods. When the PLT response against a lymphoblastoid cell line was analyzed by limiting dilution culture and determination of the reactivity of individual cultures against a panel of loss mutants of the initial stimulating LCL, a large fraction of the cultures showed the same pattern, apparently recognizing a determinant associated with DR. In two-dimensional gel analysis of several DR4-positive HLA-D region homozygous cells, the IEF pattern of the DR beta chain correlated with the Dw specificity expressed by the cell. These two pieces of evidence suggest that, although many determinants may contribute to reactivity in mixed leucocyte culture or PLT, an immunodominant determinant associated with the DR beta chain may be the most important single factor in the assignment of Dw specificity.

Epitopes↗
PubMed1980

Linkage analysis between the major histocompatibility system and insulin-dependent diabetes in families with patients in two consecutive generations.

We have histocompatibility (HLA) genotyped 28 families with insulin-dependent diabetics in two or more consecutive generations, usually parent and child. This strategy of ascertainment was used to maximize the likelihood of obtaining a homogeneous type of disease within a family, and an autosomal dominant mode of inheritance. 76 diabetics and 169 nondiabetics were studied in these families. The frequencies of the antigens Dw3 and Dw4, and the genotype Dw3/Dw4 among the diabetics are 59, 68, and 30%, respectively, as compared with 15, 12, and 2% in normal controls, and 43, 41, and 10% in the nondiabetic relatives of the diabetics. Dw2 is present in only one diabetic (4%), as compared with 18% in normal controls and 17% in nondiabetic relatives.HLA haplotype concordance was analyzed for sib pairs in relation to the haplotype shared by the affected parent/child pair, and for the diabetic sib pairs within each sibship. The results failed to reveal deviations in the expected HLA haplotype assortment. Assuming an autosomal dominant mode and several penetrance levels, linkage analysis between the HLA and diabetes was performed. The total lod score is 0.37 for a recombination fraction of 0.29 at 50% penetrance. Although the linkage and concordance analysis results are inconclusive, they seem to be different from those reported by us for families with normal parents and two or more diabetic sibs. Because ascertainment biases may have influenced these results in an unquantifiable manner, it is not certain whether the two types of families are genetically different. However, the marked difference in the lod scores for the 50% penetrant autosomal recessive model between the two types of families is compatible with a genetic dissimilarity between them. The high frequency of the Dw3 and Dw4 antigens, the Dw3/Dw4 genotype, and the decreased frequency of Dw2, however, indicate the existence of two or more important diabetic genetic factors associated with the D region of the HLA in these families.

Diabetes Mellitus, Type 1↗
PubMed1979

HLA-Dw antigens in unrelated juvenile, insulin-dependent diabetics.

Forty-one unrelated juvenile, insulin-dependent diabetics have been HLA tissue typed for A, B and Dw anitgens and compared with a normal control population. We have found statistically significant increases in the frequencies of B8, B18, and Dw3, and significant decrements in the frequencies of B7, B12 and Dw2. The log-linear modeling technique was used to study the association of JIDD with Dw3 and B8 antigens. We confirmed that the B8 excess seen in diabetics is secondary to the excess of Dw3. The decrements of B7, B12 and Dw2 could reflect an association of these antigens with a protective factor for the disease, or could be due to an artifact. The latter possibility was excluded for B7 and Dw2 by adjusting for the excess antigen frequencies. These findings suggest that the associations between the HLA and diabetes are compatible with the existence of genes which are concerned with the pathogenesis of the disease and are closely associated with the D locus of the major histocompatibility system.

Adolescent↗
PubMed1979

B lymphocyte determinants in immunoglobulin A nephropathy.

Because of our prior demonstration of a strong association betwen a specific B lymphocyte determinant and the occurrence of chronic membranoproliferative glomerulonephritis and the demonstration by others of the frequent concurrence of an IgA deposit disease, anaphylactoid purpura nephritis,with HLA-BW35, we conducted an investigation of the association among Minnesota Caucasians of the HLA markers BW35, DW1 and B lymphocyte determinants identified by three alloantisera with IgA nephropathy and the syndrome of recurrent macroscopic hematuria. The highly significant association between HLA-BW35, DW1, and B cell antigens identified by alloantisera L, B, and F, present in 50 normal Minnesota Caucasians, was not observed in 18 Minnesota patients with IgA nephropathy. The frequency of HLA-DW1 was the same among controls and patients, whereas the relative risk of developing IgA nephropathy was demonstrated to be increased 4- to 5-fold in the presence of the B cell antigens identified by alloantisera L and B. These sera appear to identify determinants on B lymphocytes associated with the disease state and possibly not intimately related to the HLA-D region. These findings emphasize the possible informativeness of defining B cell alloantisera on disease panels.

Antilymphocyte Serum↗
PubMed1977

Lymphoblastoid cell lines of homozygous typing cells used for sensitization in PLT.

Lymphoblastoid cell lines of homozygous typing cells were used as the sensitizing cells in MLC to prepare PLT cells. Results obtained using such cells against a panel of restimulating cells were compared to those obtained using regular PLT cells in which priming had been accomplished with normal peripheral blood lymphocytes. It appears that lymphoblastoid cell lines can be used for this purpose; the advantages of such an approach are given.

Cell Line↗