Ribonuclease is partly responsible for the XXXX inhibitory effect activated by HLA alloantigen recognition.

@entity2858 @entity35784 @entity30555 @entity14335
OBJECTIVE: This study was performed to determine whether ribonucleases (RNases) contribute to the soluble @entity2858 inhibitory activity that results from the recognition of HLA alloantigens. DESIGN AND METHODS: Supernatants from mixed lymphocyte reactions of peripheral blood mononuclear cells from healthy HLA-discordant individuals exhibited @entity2858 inhibitory activity (alloantigen-stimulated factors; @entity35784 ). These supernatants were tested for their sensitivity to heating (90 degrees C for 3 min), and for the presence of three RNases belonging to the @entity30555 superfamily: @entity14335 ( @entity14335 ); @entity30555 ; and angiogenin. Polyclonal antibodies specific for these RNases were used for Western blot analysis of the @entity35784 , as well as for blocking the @entity2858 inhibitory activity of @entity35784 . In addition, an RNase inhibitor (RI) was used to determine whether the anti-viral activity of @entity35784 was due to RNase activity. RESULTS: @entity2858 inhibitory activity of @entity35784 was: (i). resistant to heat treatment; (ii). blocked by 58% with an antibody specific for @entity14335 , but not with antibodies against @entity30555 or angiogenin; and (iii) blocked by 65-100% with an RI. Moreover, Western blot analysis with an anti- @entity14335 antibody detected @entity14335 in the @entity35784 . CONCLUSION: These findings indicate that the majority of the soluble @entity2858 inhibitory activity contained in the supernatants of mixed lymphocyte reactions is due to @entity14335 or a closely related RNase.
