Effects of nucleoside analogs on Epstein-Barr virus-induced transformation of human umbilical cord leukocytes and Epstein-Barr virus expression in transformed cells

Rescue of IgM, IgG, and IgA production in common varied immunodeficiency by T cell-independent stimulation with Epstein-Barr virus

We previously defined three categories of B-cell defects in common varied immunodeficiency (CVI): failure to produce IgG and IgA in response to T cell-dependent (TD) stimulation by Staphylococcus bacteria (Sac) plus pokeweed mitogen or B-cell inducing factor (BIF), failure to produce any immunoglobulin, and failure of Sac-induced proliferation and differentiation. The present study includes the responses of 22 CVI patients to T cell-independent (TI) stimulation by Epstein-Barr virus (EBV). In the majority of patients, EBV-stimulated B cells showed normal proliferation and IgM production. In addition, IgG and IgA production was in the range of that for EBV-stimulated normal cells in many patients. Among 11 patients with no TD production of immunoglobulin of any isotype, two showed normal IgM secretion in response to EBV and five others had significant but subnormal responses. Four patients never had humoral responses despite repeated testing and removal of potentially suppressing T cells and monocytes. Concanavalin A stimulation of the T cells from all the patients tested resulted in the production of B-cell inducing factor at higher levels than for normal donor T cells, as assayed on normal Sac-stimulated B cells. These results show that many cases of B-cell defects in CVI patients involving TD production of IgM, switching to TD production of IgG and IgA, and mitogen responses to Sac are not absolute defects. The B cells will respond normally to some stimuli.

Core (2'-5')oligoadenylate and the cordycepin analog: inhibitors of Epstein--Barr virus-induced transformation of human lymphocytes in the absence of interferon

The 3'-deoxyadenosine (cordycepin) analog of (2'-5')oligo(A) [(2'-5')oligoadenylate with a triphosphate at the 5' end], synthesized enzymatically from cordycepin 5'-triphosphate in lysed rabbit reticulocytes or L-cell extracts was (i) inhibitory to translation in lysed rabbit reticulocytes and (ii) metabolically stable in extracts of either L cells or C85-5C lymphoblasts. The 5' dephosphorylated (core) (2'-5')oligo(A) and the core cordycepin analog can replace human fibroblast interferon in preventing the transformation of human lymphocytes after infection with Epstein--Barr virus B95-8 (EBV) as determined by the decreased incorporation of [3H]thymidine into cellular DNA and the inhibition of morphological transformation of EBV-infected lymphocytes. Whereas the naturally occurring core (2'-5')oligo(A) was cytotoxic to uninfected lymphocytes and proliferating lymphoblasts, the core cordycepin analog was not. Human leukocyte interferon was more effective than human fibroblast interferon in the inhibition of EBV-induced transformation of human umbilical cord lymphocytes and adult peripheral blood lymphocytes.