Human leukocyte antigen effects

Polymorphism in the human leukocyte antigen (HLA) s ystem also may be an obstacle to producing an effective vaccine. A potential model for this problem is the observation that T cells, including the cytotoxic T lymphocytes, in patients with HLA-B3S do not re.spond to certain. strains of the parasite. It appears that the combination of certain proteins produced by Plasmodium strains with HLA-B3S prevents a normal T-cell re.sponse. In other words, the immune system of these patients will respond to some Plasmodium strains and not others. The implication is that an effective vaccine will have to be very polyvalent. 

The answer is d. (Murray, pp 812-828. Scriver, pp 3-45. Sack, pp 97-158. Wilson, pp 59—78.) Linkage disequilibrium describes an association between a particular polymorphic allele and a trait. Many autoimmune diseases exhibit association with particular human leukocyte antigen (HLA) alleles (i.e., HLA-B27 and ankylosing spondylitis). The association is not necessarily cause and effect (e.g., when viral infections that trigger a disease preferentially infect certain HLA genotypes). Lounder effects represent a... 

Hg is one of the few chemicals which is able to induce loss of tolerance to self-antigens in animals. This effect is human leukocyte antigen (HLA) dependent and has been demonstrated in genetically susceptible strains of rats and mice. Brown-Norway rats injected with Hg chloride (HgCl2) produce antilaminin antibodies, which attack the kidneys, causing an autoimmime glomerulonephritis (Dmet et al. 1994). The... 

Leukocyte-depleted blood products, particularly red blood cell concentrates, are clinically used to avoid negative side effects in recipients after transfusion. Possible leukocyte-associated post-transfusion complications include human leukocyte antigen alloimmunization, graft-versus-host disease, platelet refractoriness, and transmission of viruses. Amongst the various existing techniques for the selective removal of leukocytes from blood, filtration has become a popular method, because of its convenience and lowcosts. Leukocyte filters have been specially developed for the purpose they generally consist of fibrous materials made of Nylon, PAN, cotton wool, cellulose acetate,or polyester. Currendy available filters... 

Flavonoids can affect the function of plasma membrane transport Na+- and K+-ATPase, mitochondrial ATPase, and Ca2+-ATPase. The Mg2+-ectoATPase of human leukocytes is inhibited by quercetin, which acts as a competitor of ATP binding to the enzyme. The sarcoplasmic reticulum Ca2+-ATPase of muscle is effectively inhibited by several flavonoids that were also active inhibitors of antigen-induced mast cell histamine release. 

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