Israel Medical Association Journal

Background: Poliovirus rapidly evolves by nucleic acid substitutions and genetic recombination with other polioviruses and non-polio enteroviruses. Evolving oral poliovirus (Sabin strains) can rapidly revert to neurovirulence and undergo antigenic alterations.

Objectives: To evaluate the threat of vaccine-derived poliovirus (1–15% divergence from the respective Sabin strain) for a poliomyelitis-free population in a country with a long-standing routine vaccination program.

Methods: We characterized genetic and antigenic changes in OPV[1] strains isolated from sewage in Israel and evaluated intestinal immunity by measuring fecal excretion after OPV challenge of vaccinated children.

Results: Characterization of poliovirus from sewage revealed eight type 2 and three type 3 vaccine polioviruses that had replicated and started to evolve (vaccine that replicated and diverged by 0.5 to ≤ 1.0%) and nine highly diverged type 2 vaccine-derived polioviruses (1–15% divergence from the respective Sabin strain) with 8–14% divergence between the years 1998 and 2005. Six of the eleven VRPV[2] uniquely recombined with OPV and/or NPEV[3]. The nine VDPV[4] were epidemically related, genotypically neurovirulent, and had 10–15 amino acid substitutions in antigenic sites altering their antigenicity, but shared a single recombination. Type 2 OPV was excreted by 23% and 17% of infants challenged with OPV 3 months after partial immunization (two doses each of OPV and enhanced inactivated poliovirus) or full immunization (three doses of each) respectively, despite high humoral antibody titers.

Conclusions: Our findings, which show that OPV is excreted for a significant period by children with high humoral immunity, emphasize the long-term potential threat from VDPV in highly vaccinated populations. An adequate immunization program, combined with environmental surveillance, is necessary to prevent poliomyelitis and community transmission of poliovirus. 

The autoimmune lymphoproliferative syndrome is a recently described human disorder that affects lymphocyte programmed cell death (apoptosis).

Objectives: To report our experience with three patients who developed autoimmune disease following prostatectomy.

Patients: Three patients presented with autoimmune phenomenon soon after a prostectomy for BPH[1] or prostatic carcinoma: one had clinically diagnosed temporal arteritis, one had leukocytoclastic vasculitis, and the third patient developed sensory Guillian-Barré syndrome following prostatectomy.

Conclusions: In view of the temporal association between the removal of the prostate gland and the autoimmune process, combined with previously known immunohistologic features of BPH, a cause-effect relationship probably exists.

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[1] BPH = benign prostatic hypertrophy

Recent studies have implicated the dying cell as a potential reservoir of modified autoantigens that may initiate and drive systemic autoimmunity in susceptible hosts. The uridine-rich small nuclear ribonucleoprotein complex is a common target for autoantibodies present in the serum of patients with systemic lupus erythematosus and SLE[1]-overlap syndromes. Four modifications occurring in this complex during apoptosis have been described to date: the caspase-mediated cleavage of the U1-70K protein, the U1 RNA and the Sm-F protein, and the association with hyperphosphorylated SR proteins. In addition, the U1 snRNP[2] complex has been shown to translocate from its normal subcellular localization to apoptotic bodies near the surface of cells undergoing apoptosis. This redistribution might facilitate exposure of the modified components of the U1 snRNP complex to the immune system when the clearance of apoptotic cell remnants is somehow disturbed. The modifications in the U1 snRNP components during apoptosis might represent the initial epitopes to which an immune response is generated and may be the trigger for the production of autoantibodies to this complex in patients with SLE or SLE-overlap syndromes. Therefore, it can be hypothesized that the exposure of elevated levels of apoptotically modified U1 snRNP to the immune system of a genetically susceptible individual might lead to the breaking of immunologic tolerance towards the U1 snRNP complex.

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