HLA antigens

Class IIHLA molecules are expressed on the surface of antigen-presenting cells. They play a key role in presentation of processed linear peptide antigens of at least nine amino acids to T cells. Antigen is bound to the HLA antigen binding cleft formed by the a and 3 chains of the HLA class II molecule. This tri-molecular HLA-antigen complex binds in turn to the variable portion of the T-cell receptor. 

To detect HLA antigens and consequently to type tissues for transplantation. 

The MHC proteins are named after the "major histocompatibility complex —the DNA segment that codes for them. Human MHC proteins are also known as HLA antigens ( human leukocyte-associated antigens). Their polymorphism is so large that it is unlikely... 

Wallach, D., M. Fellous, and M. Revel, Preferential effect of gamma interferon on the synthesis of HLA antigens and their mRNAs in human cells. Nature, 1982. 299(5886) 833-6. 

Kakizaki S, Takagi H, Murakami M, Takayama H, Mori M. HLA antigens in patients with interferon-alpha-induced autoimmune thyroid disorders in chronic hepatitis C. J Hepatol 1999 30(5) 794-800. 

Juji T, Satake M, Honda Y, Doi Y (1984) HLA antigens in Japanese patients with narcolepsy. Tissue Antigens 24 316-319... 

Neely S, Rosenberg R, Spire J, Antel J, Arnason B (1987) HLA antigens in narcolepsy. Neurology 37 1858-1860... 

B6. Bell, D. A., and Maddison, P. J., Serologic subsets in systemic lupus erythematosus An examination of autoantibodies in relationship to clinical features of disease and HLA antigens. Arthritis Rheum. 23, 1268-1273 (1980). 

Figure 1.3. Diagram of cell membrane. The plasma membrane is a lipid bilayer containing peripheral proteins, including HLA antigens, proteoglycans, and integral proteins, such as pore-forming proteins that transverse the cell membrane.

If there is an HLA association for olanzapine, it seems to be different from the HLA antigens incriminated for clozapine (SEDA-25, 66). 

Terasaki, S., Nakanuma, Y., Ogino, H., Unoura, M., Kobayashi, K. Hepatocellular and biUary expression of HLA-antigens in primary biUary cirrhosis before and after ursodeoxychoUc acid therapy. Amer. X Gastroenterol. 1991 86 1194-1199... 

Rivera R, Scornik JC. HLA antigens on red cells. Implications for achieving low HLA antigen content in blood transfusions. Transfusion 1986 26(4) 375-81. 

Kaminski ER, Hows JM, Goldman JM, Batchelor JR. Pretransfused patients with severe aplastic anaemia exhibit high numbers of cytotoxic T lymphocyte precursors probably directed at non-HLA antigens. Br J Haematol 1990 76(3) 401-5. 

In 10 patients with bucillamine-associated interstitial pneumonitis, the HLA antigen DR4 was present in all 10 and a positive lymphocyte stimulation test was found in three of the six patients tested (3). 

Of 34 cases of aplastic anemia (mean age 41 years, mean time of felbamate exposure 154 days), 20 occurred in combination with other compounds implicated as a possible cause of aplastic anemia and 5 occurred concurrently with viral infections (7). Although 5 patients were taking felbamate monotherapy, 13 of the 34 suffered from autoimmune disease, and 1 was receiving cytostatic therapy. Past allergic or toxic reactions to other anticonvulsants were reported by 65% of the patients and blood dyscrasias by 45%, while 32% had serological evidence of a previous immune disorder. Eight of nine patients tested had experienced at least one episode of aplastic anemia associated with HLA antigens. 

Hakala M, van Assendeht AH, Ilonen J, Jalava S, Tiilikainen A. Association of different HLA antigens with various toxic effects of gold salts in rheumatoid arthritis. Ann Rheum Dis 1986 45(3) 177-82. 

In spite of the similarities, there are some differences between spontaneous and penicillamine-induced myasthenia in respect to genetics. Myasthenic reactions to penicillamine appear to occur in a special genetic subgroup of patients, in whom there is a higher prevalence of the HLA antigens DRl and Bw35, and a lower prevalence of the antigens DR3 (which is associated with idiopathic myasthenia) and DR4 (which is increased in rheumatoid arthritis) (112,113). 

Moens HI, Ament BJ, Feltkamp BW, van der Korst JK. Longterm foUownp of treatment with D-penicillamine for rheumatoid arthritis effectivity and toxicity in relation to HLA antigens. J Rheumatol 1987 14(6) 1115-19. 

Garlepp MI, Dawkins RL, Christiansen FT. HLA antigens and acetylcholine receptor antibodies in penicillamine induced myasthenia gravis. BMJ (CUn Res Ed) 1983 286(6375) 1442-3. 

Scherak O, Smolen JS, Mayr WR, Mayrhofer F, Kolarz G, Thumb NJ. HLA antigens and toxicity to gold and penicillamine in rheumatoid arthritis. J Rheumatol 1984 11(5) 610-14. 

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