PubMed HealthSearch

Biomedical subjects

A Bratlie

Publications and source records attributed to A Bratlie.

At least 19 recordsLinked to original sources

A cytotoxic monoclonal human hybridoma antibody (TrJ3) against HLA-B44(12) and -B45(12).

We have generated a human monoclonal cytotoxic IgM lambda antibody (TrJ3) that reacted specifically with all lymphoblastoid B-cell lines expressing HLA-B44(12) and B45(12). TrJ3 hybridoma supernatant was suitable for HLA-B12 typing of freshly isolated blood mononuclear cells. Analysis of available amino acid sequences of HLA-B molecules indicated that the alpha 1 domain does not contain the TrJ3 serological epitope. Since HLA-B44 is associated with a unique serine residue at position 167 that points towards the peptide binding groove, we propose that S167 of the alpha 2 domain helix is a critical part of the TrJ3 epitope.

Amino Acid Sequence

Two cytotoxic human-human hybridoma antibodies to HLA: TrAH10 (anti A3.1) and TrAG2 (anti B7, Bw42).

Two cytotoxic human-human hybridoma IgM antibodies to HLA were generated by EBV transformation of PBMC from multiparous women and fusion of EBV transformed cells with the human fusion partners KR4 or KR12. Both mAbs required the sensitive immunomagnetic cytotoxicity method to display killing of freshly prepared PBMC. One mAb (TrAH10) was specific for HLA-A3. Strikingly, TrAH10 reacted much more strongly with lymphoblastoid cell lines of HLA-A3.1 than of the rare variant HLA-A3.2, previously detected by cytotoxic T cells. Thus, in the microcytotoxicity test, the titer of concentrated TrAH10 was approximately 2000 times higher for A3.1 as compared to A3.2, and a clear difference was also observed in radioimmunoassay. Since the two HLA-A3 variants differ by only two amino acids at positions 152 and 156 of the alpha 2-domain's alpha-helix, the epitopes defined by the mAb TrAH10 and HLA-A3.1 specific cytotoxic T cells must be closely related. The observations with TrAH10 suggest that the HLA polymorphism detected by human mAbs may turn out to be as extensive as the T-cell defined HLA polymorphism. The other mAb (TrAG2) bound B7 and Bw42 with equal strength, and in addition bound weakly to some cells that were Bw22 or B39. Magnetic polymerbeads coated with affinity purified human mAbs TrAH10 or TrAG2 formed rosettes with EBV transformed cells carrying relevant HLA antigens; however, rosette formation with freshly isolated PBMC was very weak and unsuitable as a typing assay.

Antibodies, Monoclonal

A cytotoxic human-human hybridoma antibody (TrC7) specific for HLA-A29.

TrC7 is a cytotoxic IgM human-human hybridoma anti-HLA Ab. Its reaction pattern with a panel of 48 HLA-typed EBV-transformed cell lines and PBMC from 348 HLA-typed individuals correlated precisely with expression of HLA-A29. TrC7 did not react with HLA-A30, -31, -32 or -w33, which, like A29, are splits of Aw19.

Antibodies, Monoclonal

Four cytotoxic human-human hybridoma antibodies that react with HLA-B27.

PBMC were isolated from a multiparous woman with HLA-B27 specific Abs in her serum. The HLA type of the donor was A2,9:B7. The PBMC were EBV transformed, and four cell lines making cytotoxic Abs to HLA-B27+ cells prepared. Hybridomas were constructed by fusing the EBV lines with the human fusion partner KR4. All four mAbs were of IgM isotype. One mAb (TrBH12) reacted specifically with B27+, B37+ and Bw47+ lymphoblastoid cell lines and with all B27+ PBMC except for a rare variant so far found only in one Norwegian family. Another mAb (Tr3B6) was cytotoxic for all B27+ cells tested, including the TrBH12- variant; in addition, it showed weaker cross-reactions to Bw42, B49 and a cell line with the probable phenotype B7,38. Supernatant from the Tr3B6 hybridoma was tested in lymphocytotoxicity against a panel of 658 individuals, 141 of whom were B27+. With this panel, Tr3B6 showed perfect correlation with HLA-B27. The two last mAbs (TrCG10 and TrBF1) reacted with all B27+ cells tested, but in addition showed quite extensive cross-reactions.

Antibodies, Monoclonal

HLA class I and II typing using cells positively selected from blood by immunomagnetic isolation--a fast and reliable technique.

This paper describes a new cell isolation and HLA typing technique, which permits cell separation and HLA class I or class II typing to be performed in 70 min. Magnetic monodisperse microspheres (Dynabeads TM) were coated with monoclonal antibodies (MAbs) specific for the CD8 T cell antigen or for HLA class II monomorphic epitopes. They could then be used to obtain HLA class I or class II positive cells directly from ACD blood in approximately 15 min by the use of magnetic separation. The cells (attached to the microspheres) were subsequently used in microcytotoxic HLA typing (total incubation time of 55 min) using acridin orange/ethidiumbromide to stain viable (yellow) and dead (red) cells. It was found that this immunomagnetic (IM) HLA typing technique was specific, has a sensitivity superior to that observed for conventional microcytotoxicity assays and gave low background staining. IM HLA-ABC typing of 50 healthy donors and 10 patients and IM HLA-DR typing of 25 healthy donors and 30 patients gave results corresponding well with that obtained independently by conventional HLA typing (concordancy rates 92-100%). Furthermore, the IM HLA typing technique permitted reliable HLA class II typing of blood cells from six patients where conventional HLA class II typing was impossible. The IM HLA typing technique also enables HLA class I and II typing to be quickly and reliably performed on cells from ACD blood of cadaveric donors.

Antibodies, Monoclonal

HLA genotypes in a family with a case of homozygous C2 deficiency and discoid lupus erythematosus.

A fifty-year-old man with a history of recurrent bronchial and renal infections, and rheumatoid arthritis was admitted with a sunexposure-induced discoid lupus erythematosus. Complement levels and HLA typing of the patient and his family revealed a homozygous C2 deficiency in the patient and his HLA-identical healthy younger sister. The C2 deficiency gene was associated with HLA-A10, B18, DR2, C4A4B2, BfS on one chromosome and with HLA-A2, B7, DR2, C4A4B2, BfS on the other.

Arthritis, Rheumatoid

Significance of HLA matching in renal transplantation. A prospective one-center study of 485 transplants matched or mismatched for HLA-A, B, C, D, and DR antigens.

Matching for HLA haplotypes as well as for HLA-A and B antigens improved graft survival in 112 living related first transplants. In cadaveric first transplants, matching for HLA-A and B antigens had a beneficial effect on the fate of 373 grafts, while matching for HLA-C antigens had no predictive value. One hundred seventeen cadaveric transplants and their recipients were prospectively typed for the HLA-DR antigens. Compatibility for HLA-DR was found to be prognostically beneficial irrespective of matching for HLA-A and B antigens, and with no difference between transfused and nontransfused patients. Matching both for HLA-A , B and D/DR was thus found to influence the outcome of renal transplantation.

Adult