PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “Histocompatibility Testing”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

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

At least 1,117 records · Page 62Linked to original sources

Advances in HLA genetics.

The major histocompatibility complex (MHC) is a genetic system of over 70 known genes that occupies the midportion of the short arm of the sixth chromosome (C6p) and spans about 4 million base pairs of DNA. The high-resolution typing of class I and class II MHC genes and the identification of genes between and near them has increased the definition of the genetic basis of immune responses and diseases of unknown etiology such as autoimmune diseases in man. Although there are many more genetic systems that participate in the rejection of tissues and in the immune response, the MHC plays a central role in tissue compatibility and immune response against cancer and infectious diseases. In this paper, the authors review evidence about the role of HLA polymorphism in the pathogenesis and development of cancer, infectious diseases, autoimmune diseases and transplantation.

Animals↗

Effects on C-reactive protein on the lymphoid system. I. Binding to thymus-dependent lymphocytes and alteration of their functions.

C-reactive protein (CRP) is an acute phase protein which shares with the immunoglobulins the ability to induce precipitation and agglutination reactions and activate the complement system. We report here that purified human CRP binds selectively to human T lymphocytes, inhibits their ability to form spontaneous rosettes with sheep erythrocytes and inhibits their response to allogeneic cells in mixed lymphocyte culture reactions; it fails to inhibit phytohemagglutinin- or concanavalin-A-induced mitogenesis. CRP does not bind to human B lymphocytes, nor does it alter the following B-cell functions: binding to activated complement components or the Fc portion of immunoglobulins, mediation of antibody-dependent cytotoxicity reactions or the ability of allogeneic cells to stimulate a mixed lymphocyte culture reaction. Human CRP shows similar selective binding with murine T lymphocytes. It therefore seems that binding of CRP is a property of T lymphocytes or a subpopulation thereof, and can result in modulation of certain of the T-cell functional characteristics in vitro. We suggest that CRP may play a role in modulating T-cell functions during the inflammatory state.

Animals↗

Reactions of kidney cells with cytotoxic antisera: possible evidence of kidney-specific antigens.

HL-A typing of cadaver kidney cell suspension by fluorochromasia cytotoxicity was successful in 76 out of 124 cases. In the 44 cases with confirmed phenotypes, 24 had identical results for lymphocytes and kidney cells. Twenty kidney cells had HL-A antigens not detected on that donor's lymphocytes, most commonly HL-A7 and HL-A8. In eight of these 20 cases, the additional kidney antigens brought the total to more than two per segregant sereis, in disagreement with an earlier report from this laboratory. The discrepancy was traced to a change in the method of complement preparation. The complement was successfully deprived of the resulting non-specific cytotoxicity for kidney cells by absorption with human red blood cells. Prior to absorption, the complement had rendered kidney cells susceptible to the lytic effect of anti-A and B red cell antibodies. Using the absorbed complement, a patient who had hyperacutely rejected two cadaver kidneys provided sera with an antibody reacting with, and absorbed by, the kidney cells but not the lymphocytes of the donors.

Antigen-Antibody Reactions↗

Improved renal allograft survival using the mixed lymphocyte culture for selection of nonidentical living related donors.

Our results concur with earlier published work, by other groups, showing that LRD-recipient pairs with low MLC stimulation usually have better and more prolonged graft success than do those with higher stimulation. Specific HL-A compatibilities or incompatibilities did not seem to affect these results, nor did the presence of an increased number of common loci, short of increasing the apparent chromosome compatibility. The presence of pre-transplant cytotoxic antibodies, in patients with a high MI, however, may unfavorably affect the LRD transplant. The overall results of our LRD transplant experience is shown in Figure 1, and superimposed upon Figure 2, is the current extrapolation of data showing MLC stimulation and haplotype success. Thus, it appears that graft survival may be improved and more closely approach the levels seen in a full-house, diplotype match, by using the MLC results in considering patients for transplantation. Not all patients with a high MLC, however, (see table) reject their grafts and it is impossible to predict pre-transplant who will develop specific allograft enhancement. Before the MI becomes a specific criteria for transplant selection, additional studies of patient stimulation in MLC should be done. Suppression of stimulation by donor cells in autologous serum, as compared to the response to unrelated controls, might provide pre-transplant clues to the presence of enhancing factors. Such studies could provide an index that would be more meaningful than the MI in AB sera alone. Since overall results from both our series and from the Transplant Registry continue to indicate better long term graft survival for LRD than for cadaver transplants, and since the evidence suggests that a successful transplant offers a patient a better quality of life, as well as decreased morbidity and mortality compared to concomitant time spent on hemodialysis, continued LRD transplants with high MI is warranted in some circumstances with the patient's understanding of the overall outcome and backgrouns. Until in vitro tests can be more predictive of individual rather than statistical graft success, the patient with an LRD and a high MI should be given a complete explanation of the probabilities for success or failure, and he and the donor allowed to make an informed decision. The following are guidelines that we proposed for the selection of LRD transplants: 1. Availability and willingness. 2. Medical and psycho-social clearance. 3. ABO compatibility. 4. Negative direct crossmatch. 5. HL-A diplotype or haplotype. 6. MI less than 10 if possible, with or without HL-A antibodies. 7. MI greater than 10 with no HL-A antibodies, if possible. 8. MI greater than 10, with HL-A antibodies, if both donor and recipient clearly understand the enhanced chance for failure.

ABO Blood-Group System↗

Immunological reactions involving leukocytes: I. Detection of antibodies to human granulocytes by measurement of the metabolic events associated with phagocytosis.

During phagocytosis, glucose oxidation via the hexose monophosphate shunt (HMS) is markedly stimulated in human polymorphonuclear leukocytes. A method is described for the detection of antibodies to human granulocytes which exploits this fact. The source of antibodies was rabbit antihuman leukocyte serum (RAHLS) obtained by repeated immunization of normal rabbits with human granulocyte homogenates. HMS activity was quantitated by measuring the release of 14CO2 from glucose-1-14C. Under precisely defined experimental conditions, RAHLS and its IgG fraction inhibited 14CO2 release. The inhibitory effect of RAHLS on human granulocyte phagocytosis-associated HMS activity could be reduced by prior absorption of RAHLS with human granulocytes. Compared to the cytotoxic and leukoagglutination tests, this method appears more sensitive with respect to detection of xenogeneic antibodies to human granulocytes.

Absorption↗

Selection of unrelated bone marrow donors: does the current procedure warrant complete MHC class II identity?

Bone marrow transplantation from unrelated donors is being used increasingly for the treatment of patients with leukemia and several other hematologic disorders. Selection of unrelated bone marrow donors currently relies on serological HLA identity and negative mixed lymphocyte reactions between donor/recipient pairs. As serological HLA-DP typing is not feasible, we used the HLA-DPB1 oligonucleotide typing method to investigate whether the current selection procedure can guarantee complete MHC class II identity. In 40 consecutive patients, one third (62/193) serologically HLA-A, -B, -C, -DR and -DQ identical donors were found to be MLC-negative with a relative response below 5%. HLA-DPB1 oligonucleotide typing of these MLC-negative donors revealed that again only one third (20/62) was also identical for DP with their presumptive recipients. In the majority of pairs a disparity in graft-versus-host direction or in host-versus-graft direction of at least one allele was seen. These data indicate that, in spite of the strict MLC criteria used, the current procedure did not warrant complete MHC class II identity. This implies that oligotyping for DPB1 can improve matching and should be introduced for typing of volunteers.

Bone Marrow Transplantation↗