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 145 records · Page 8Linked to original sources

Comparative histocompatibility testing of seven calcium phosphate ceramics.

Five hydroxyapatite and two tricalcium phosphate ceramics were implanted in rat femora for one to six months. They were compared with each other in regard to biocompatibility and bone induction. After one month bone had grown directly on to the surface of all implants. After six months the on-growth of bone had increased with the exception of two dense HA materials. In these materials some bio-degradation had occurred with subsequent formation of a wide macrophage interlayer. Bio-degradation and biocompatibility of calcium phosphate ceramics seem to depend not only on density but also on other factors. Induction of bone could not be observed in soft tissue environment.

Animals↗

Multilaboratory evaluation of serum analysis for HLA antibody and crossmatch reactivity by lymphocytotoxicity methods.

CONTEXT: This report presents results of the serum antibody analysis and crossmatch challenges in the proficiency testing program for histocompatibility testing jointly sponsored by the American Society for Histocompatibility and Immunogenetics and the College of American Pathologists. OBJECTIVE: To obtain information about consensus rates among participating laboratories that reported antibody screening and crossmatch results by direct complement-dependent lymphocytotoxicity (CDC) and/or anti-human globulin (AHG)-augmentation methods. DESIGN: We analyzed responses from approximately 165 laboratories participating in 32 surveys during 1993-2000. Most of the testing was done by CDC methods, but increasing proportions of laboratories are using AHG augmentation of these techniques; almost one half of the serum screenings and crossmatches were done by AHG. RESULTS: A total of 40 serum specimens were screened to determine the percent panel-reactive antibody (PRA) and identify HLA-specific antibodies. Participants often reported very wide ranges of PRA values. Panel-reactive antibody ranges exceeded 60 percentage points for 16 (40%) of the serum screening results by CDC and for 31 (77%) of the results by AHG. The interlaboratory variability of PRA values suggests that in many laboratories, the CDC or AHG procedures were often too insensitive or overly sensitive. The antibody identification results revealed inconsistent patterns among the participants performing CDC or AHG screening. Most participants reported the same primary antibody specificities by both methods. The consensus levels were generally high for the monospecific sera. On the other hand, there was much less agreement among the participants if the sera reacted with 2 or more HLA antigens. Participants using the more sensitive AHG method reported additional antibody specificities in many specimens, but invariably the consensus levels were rather low. A total of 192 serum-cell combinations were used for the crossmatch challenges. There was considerable interlaboratory variability; 21% of the CDC crossmatches and 36% of AHG crossmatches failed to reach the 90% consensus threshold. CONCLUSIONS: This experience demonstrates considerable inconsistencies in serum screening and crossmatching among laboratories participating in the American Society for Histocompatibility and Immunogenetics/College of American Pathologists surveys. A lack of uniformity in test results may limit the efficient application of these methods in a clinical setting. Standardization of crossmatch and antibody screening techniques is highly desirable.

Antibody Specificity↗

Error rate for HLA-B antigen assignment by serology: implications for proficiency testing and utilization of DNA-based typing methods.

Until recently, the majority of HLA class I typing has been performed by serology. Expensive commercial typing trays are frequently used for testing non-Caucasian subjects and new strategies using DNA-based methods have been adopted for improving clinical histocompatibility testing results and adapted as supplements in proficiency testing. A double-blind comparison of the typing of HLA-B specificities in 40 samples was carried out between serology and two polymerase chain reaction (PCR) methods, PCR amplification with sequence-specific primers (PCR-SSP) and PCR amplification and subsequent hybridization with sequence-specific oligonucleotide probes (PCR-SSOP). The results demonstrated 22.5% misassignments of HLA-B antigens by serology. There was complete concordance between the results obtained with the two PCR based typing methods. A second panel of 20 donor samples with incomplete or ambiguous serologic results was analyzed by PCR-SSP and SSOP Both PCR methods identified correctly the HLA-B antigens. Our results suggest that more accurate typing results can be achieved by complementing serologic testing with DNA-based typing techniques. The level of resolution for HLA-B antigen assignment can be obtained by this combination of serology and limited DNA-based typing is equivalent to the HLA-B specificities defined by the WHO-HLA Committee. This level of resolution cannot routinely be achieved in clinical histocompatibility testing or in proficiency testing using serologic reagents only.

DNA↗

Factors influencing the outcome of kidney transplants.

This study is a multifactorial analysis of 389 transplants performed from June 1977 to December 1981. Analysis of the effects of transfusions antilymphocyte serum (ALS), histocompatibility testing, gender, and patient risk factors (presence of concomitant disease, greater than 50 years of age, etc.) was done. Two-hundred fifty-three patients received cadaver kidneys and 136 patients obtained kidneys from a relative. Two-hundred eighty-three (73%) patients received blood transfusions prior to transplantation. Our data showed that recipients receiving transfusions prior to transplantation had a significantly higher graft survival than those who were not transfused in both cadaveric and related graft recipients. Two-hundred twenty-one (56%) patients received ALS following the transplant. This group had a 15% higher graft survival than a comparable group. Analysis of histocompatibility testing data shows approximately 5% higher functional graft survival between each match grade. Surprisingly, female patients receiving kidneys from living related donors had a 16% higher graft survival than male patients. In cadaver recipients female patients had a 10% higher patient survival as compared to male patients. The risk factor status of recipients affected not only graft survival but patient survival, which probably is due to the consequences of immunotherapy. The authors' conclusion is that the above mentioned factors may be additive in nature. Further, multivariable analysis is necessary in order to correctly transplant data.

Antilymphocyte Serum↗