Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Histocompatibility Testing”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 937 records · Page 52Linked to original sources

Serological characterization of human monocytes for HLA, B-lymphocyte, granulocyte, and monocyte-associated antigens by cytotoxicity testing.

Highly enriched preparations of monocytes, B and T lymphocytes, and granulocytes from 18 normal donors were serotyped in parallel in a complement-dependent cytotoxicity assay using allogeneic and heterologous antisera defining three independent tissue antigen systems. HLA and B-lymphocyte tissue antigens were detected on human monocytes although granulocyte antigens were absent. By cytotoxicity testing the presence of Ia-like antigens on monocytes was significantly diminished compared to the autologous B-lymphocyte population and has important implications in B-lymphocyte serology. The study indentified a number of human antisera obtained from multitransfused subjects and pre- and post-transplant organ recipients that were non-HLA and appeared to define monocyte-associated antigens. The serological implications of surface antigen expression on human monocytes compared with other peripheral blood cells are discussed.

B-Lymphocytes↗

Utilization of murine peripheral blood lymphocytes for H-2 typing.

We adapted the NIH Standard Protocol for HLA-A, B, C typing to perform murine H-2 typing. The assay is direct, measuring the cytotoxicity of the antiserum/cell/complement reaction with a supravital dye. This method is advantageous because it: utilizes peripheral blood lymphocytes (PBL) obtained from the tail vein; uses microliter volumes of antiserum; is practical because the formalin fixed reactions need not be read immediately; involves standard and inexpensive cytotoxicity techniques; is easily interpreted and is readily reproducible.

Animals↗

A one-step monoclonal antibody typing procedure that simplifies HLA class I and class II typing.

We have developed monoclonal antibodies to most HLA specificities, making it possible for us to devise a simple, rapid, one-step microcytotoxicity test. The test is performed by adding 1 microliter of cells to 1 microliter of antibody-complement mixture predotted on the microtest tray. The reactions are read following a 1-hour incubation period (30 minutes in some instances). The analysis of reactions seen on testing 105 class I antibodies and 50 class II antibodies is shown. A comparison of typing by the standard NIH method and the new one-step procedure showed a > 96% concordance in the 500 T cells and 200 B cells we examined. Class I and class II typing could be performed using B cells, thus obviating the need to isolate both T and B cells for HLA typing.

Antibodies, Monoclonal↗

Association between major histocompatibility antigen and reproductive performance.

Many studies have both supported and refuted an association between HLA antigens and reproductive performance. To clarify these discrepant results, HLA antigens from 59 couples experiencing recurrent spontaneous abortions and 79 couples with unexplained infertility were compared with 51 fertile couples. Patients with recurrent spontaneous abortions were classified as either primary (no children) or secondary (abortions after having children or stillbirths) aborters, and patients with unexplained infertility were classified as primary (never pregnant) or secondary (previously pregnant) infertiles. The amount of antigenic disparity, homozygosity, and the probability of producing a heterozygotic offspring were analyzed for each group. Significantly more disparities at combined HLA loci and at DR loci were observed when childbearing controls were compared with primary aborters. Significant disparity between controls and secondary aborters was at the DQ locus. Total homozygosity as well as homozygosity at DR and DQ loci were significantly increased among primary aborters, but not secondary aborters, and at the B locus among secondary, but not primary infertile couples. Significant association in probability of heterozygote production was seen at the DQ locus in patients with primary infertility. These results indicate that controversy involving association of HLA and reproductive performance can be explained by properly classifying recurrent spontaneous aborters and unexplained infertiles.

Abortion, Habitual↗

Specific inhibitory substance to the husband's HLA allotype in sera from patients with gestational trophoblastic disease detected by lymphocytotoxicity testing.

The sera of nine patients with gestational trophoblastic disease were investigated for the inhibitory substance specific to the HLA allotypes of the patients' husbands by microcytotoxicity inhibition testing using monoclonal antibodies (anti-A2, A9, A10) and HLA-typing serum to Bw52. The specific inhibitory substance was present in three of three choriocarcinoma patients, in three of four invasive mole patients, and in one of two hydatidiform mole patients and seemed to change in titer parallel with tumor growth. These facts suggest that the inhibitory substance could have some relation to the patient's immunological response against the tumor; that is, this inhibitory substance could be the reason why patients could not induce graft rejection response to trophoblastic tumor cells.

Antibodies, Monoclonal↗

Standardization of flow cytometric crossmatch (FCXM) for investigation of unexplained habitual abortion.

PROBLEM: To define a positive flow cytometric crossmatch (FCXM), in terms of channel shift, for maternal IgG and IgM (n = 28) against paternal T and B lymphocytes. METHOD: A reference range study. Mononuclear cells were obtained from 28 healthy volunteers using density gradient separation of heparinized blood, followed by pre-incubation with goat immunoglobulin. A total of twelve tubes were prepared for each volunteer. Primary incubation was with negative control serum, positive control sera (either IgG or IgM) and individual AB sera. Secondary incubation was with four combinations of fluorochromes: CD3 PE/IgG-Fc F(ab')2FITC, CD3 PE/IgM F(ab')2FITC, CD20 PE/IgG-Fc F(ab')2FITC and CD20 PE/IgM F(ab')2FITC. The cells were then analyzed with an EPICS Profile flow cytometer, using 256-channels and a four decade log scale. RESULTS: The linear mean channel fluorescence of the negative control serum was subtracted from the individual AB sera (channel shift) for each of the four combinations of fluorochromes. By determining the 95% one-sided upper reference limits of the negative control serum for each of the four trimmed data sets, we clinically defined a positive FCXM for bound IgG or IgM to T lymphocytes as a shift of 10 or more channels, and for bound IgG or IgM to B lymphocytes as a shift of 25 or more channels, above the linear mean channel shift of the negative control serum. CONCLUSION: Positive FCXMs were defined for maternal IgG and IgM against T and B lymphocytes, in terms of channel shift above the linear mean channel fluorescence of the negative control serum. By standardizing the dual-color FCXM methodology, the clinical significance of alloantibodies in the maintenance of pregnancy could be addressed in a collaborative manner.

Abortion, Habitual↗

Acute graft versus host disease after liver transplantation: patterns of lymphocyte chimerism.

The diagnosis of acute graft versus host disease (aGVHD) following liver transplantation can be difficult, since many of the clinical signs can be caused by drug reactions or viral infections. To establish criteria for the persistence of donor T-cells versus engraftment, we measured donor T-cells by short tandem repeat (STR) assays in 49 liver transplant patients for 8 or more weeks post-transplant. Donor CD3+ T-cells were detected in 38 of 49 patients, on POD 2 with a mean level of 5%. The top of the 99% confidence interval for weeks 1, 2, 3, 4 and 8 were 11, 6, 3, 2 and 3%. Donor CD8+ T-cells were measured in eight patients. The level of CD8+ T-cells was much less than that for CD3+ T-cells, except in two cases of apparent aGVHD. One patient developed severe aGVHD with donor T-cells as high as 84%. The other had 10% donor T-cells for more than 16 weeks associated with fever and neutropenia. We tested the sensitivity of PCR-ssp typing of HLA DR/DQ for donor T-cells. At least one donor type was detected in all samples with 1% or more donor DNA. Thus, higher levels of donor T-cell chimerism, particularly with a high proportion of CD8+ T-cells, strongly supports a diagnosis of aGVHD.

Acute Disease↗

Linkage of Crohn's disease to the major histocompatibility complex region is detected by multiple non-parametric analyses.

BACKGROUND: There is evidence for genetic susceptibility to Crohn's disease, and a tentative association with tumour necrosis factor (TNF) and HLA class II alleles. AIMS: To examine the potential of genetic linkage between Crohn's disease and the MHC region on chromosome 6p. METHODS: TNF microsatellite markers and, for some families, additional HLA antigens were typed for 323 individuals from 49 Crohn's disease multiplex families to generate informative haplotypes. Non-parametric linkage analysis methods, including sib pair and affected relative pair methods, were used. RESULTS: Increased sharing of haplotypes was observed in affected sib pairs: 92% (48/52) shared one or two haplotypes versus an expected 75% if linkage did not exist (p=0.004). After other affected relative pairs were included, the significance level reached 0.001. The mean proportion of haplotype sharing was increased for both concordant affected (pi=0.60, p=0.002) and unaffected sib pairs (pi=0.58, p=0. 031) compared with the expected value (pi=0.5). In contrast, sharing in discordant sib pairs was significantly decreased (pi=0.42, p=0. 007). Linear regression analysis using all three types of sib pairs yielded a slope of -0.38 at p=0.00003. It seemed that the HLA effect was stronger in non-Jewish families than in Jewish families. CONCLUSIONS: All available analytical methods support linkage of Crohn's disease to the MHC region in these Crohn's disease families. This region is estimated to contribute approximately 10-33% of the total genetic risk to Crohn's disease.

Alleles↗

One year's experiences with two different image analysis systems for automated reading of the contrast fluorescence test.

We have tested two different personal-computer based color image analysis systems for automated reading of the microlymphocytotoxicity test (LCT) for HLA-A,B,C-typing and screening. Over 17,000 single LCT-reactions were prepared using the simultaneous double fluorescent variant of the LCT (contrast fluorescence test, CFT). All tests were read visually by experienced laboratory staff members. For image analysis, an automated scanning system was used. In a first step, reactions were recorded on a videotape recorder using a color(CCD)-video camera. In a second step, the recorded reactions were analyzed with the two different image analysis systems by specifically developed programs. Good correlation (r = 0.89) of the score values assigned by digital image analysis with the visual tray reading was obtained. Since also the other main performance characteristics of the prototype system (throughput, reliability, compatibility) were acceptable for routine application, we may conclude that digital image analysis is a feasible and very interesting new technique for automated evaluation of the LCT.

Algorithms↗