Vaccinations and risk of systemic lupus erythematosus and rheumatoid arthritis: A systematic review and meta-analysis

BACKGROUND

In the past several years, more and more studies proposed some concerns on the possibly increased risk of autoimmune diseases in individuals receiving vaccinations, but published studies on the associations of vaccinations with risks of systemic lupus erythematosus (SLE) and rheumatoid arthritis (RA) reported conflicting findings. A systematic review and meta-analysis was carried out to comprehensively evaluate the relationship between vaccinations and risk of SLE and RA.

METHODS

Pubmed, Web of Science and Embase were searched for observational studies assessing the associations of vaccinations with risks of RA and SLE. Two authors independently extracted data from those eligible studies. The quality of eligible studies was assessed by using the Newcastle-Ottawa Scale (NOS). The pooled relative risk (RR) with 95% confidence intervals (CIs) was used to measure the risk of RA and SLE associated with vaccinations, and was calculated through random-effect meta-analysis.

RESULTS

Sixteen observational studies were finally considered eligible, including 12 studies on the association between vaccinations and SLE risk and 13 studies on the association between vaccinations and RA risk. The pooled findings suggested that vaccinations significantly increased risk of SLE (RR=1.50; 95%CI 1.05-2.12, P=0.02). In addition, there was an obvious association between vaccinations and increased risk of RA (RR=1.32; 95%CI 1.09-1.60, P=0.004). Meta-analysis of studies reporting outcomes of short vaccinated time also suggested that vaccinations could significantly increase risk of SLE (RR=1.93; 95%CI 1.07-3.48, P=0.028) and RA (RR=1.48; 95%CI 1.08-2.03, P=0.015). Sensitivity analyses in studies with low risk of bias also found obvious associations of vaccinations with increased risk of RA and SLE.

CONCLUSION

This study suggests that vaccinations are related to increased risks of SLE and RA. More and larger observational studies are needed to further verify the findings above and to assess the associations of vaccinations with other rheumatic diseases.

Adjuvant immunization induces high levels of pathogenic antiphospholipid antibodies in genetically prone mice: another facet of the ASIA syndrome

Adjuvants may induce autoimmune diseases in susceptible individuals, a phenomenon recently defined as autoimmune/inflammatory syndrome induced by adjuvants (ASIA). Patients with both antiphospholipid antibodies (aPL) and the genetic coagulopathy factor V Leiden (FVL) are frequently found. We therefore evaluated whether adjuvant can induce aPL in heterozygous FVL mice. aPL were measured in naïve mice and at 1 and 5 months after immunization with either complete or incomplete Freund's adjuvant (CFA, IFA) in FVL and control C57/B6 background mice. We defined antibody levels 3 SD above the mean of C57/B6 mice immunized with adjuvant as positive (specificity of 99%). For β(2)GPI-dependent aPL, 28.6% (6/21) of FVL mice 5 months after immunization with adjuvant (both IFA and CFA) were positive compared with 4.8% (1/22) of FVL mice 1 month after adjuvant and 0% of naïve FVL and C57/B6 mice (0/16, p < 0.001). aPL levels correlated with behavioral hyperactivity in the staircase test. FVL mice immunized with adjuvant did not develop β(2)GPI-independent aPL. We hypothesize that the FVL aPL association is not a coincidence, but that chronic coagulation defects combined with external inflammatory stimuli analogous to adjuvant may induce aPL and also antiphospholipid syndrome, thus supporting the notion of ASIA.

Systemic lupus erythematosus following HPV immunization or infection?

Background and purpose: The link between autoimmunity and infectious agents has been strongly suggested by reports of lupus or lupus-like syndromes following immunization. This report describes three patients with either newly diagnosed systemic lupus erythematosus (SLE) or SLE flare, following vaccination for human papilloma virus (HPV). Case 1: A 17-year-old female completed two doses of HPV vaccine uneventfully. Two months later, she developed arthralgias with pruritic rashes on both lower extremities, later accompanied by livedo reticularis, bipedal edema with proteinuria, anemia, leucopenia, hypocomplementemia and high titers of anti-nuclear antibody (ANA) and anti-double-stranded DNA (anti-dsDNA). Kidney biopsy showed International Society of Nephrology/Renal Pathology Society Class III lupus nephritis. She was started on high dose steroids followed by pulse cyclophosphamide therapy protocol for lupus nephritis, and subsequently went into remission. Case 2: A 45-year-old housewife, previously managed for 11 years as having rheumatoid arthritis, had been in clinical remission for a year when she received two doses of HPV immunization. Four months later, she developed fever accompanied by arthritis, malar rash, oral ulcers, recurrent ascites with intestinal pseudo-obstruction, and behavioral changes. Cranial MRI showed vasculitic lesions on the frontal and parietal lobes. Laboratory tests showed anemia with leucopenia, hypocomplementemia, proteinuria, ANA positive at 1:320, and antibodies against dsDNA, Ro/SSA, La/SSB and histone. She improved following pulse methylprednisolone with subsequent oral prednisone combined with hydroxychloroquine. Case 3: A 58-year-old housewife diagnosed with SLE had been in clinical remission for 8 years when she received two doses of HPV immunization. Three months later, she was admitted to emergency because of a 1-week history of fever, malar rash, easy fatigability, cervical lymph nodes, gross hematuria and pallor. Laboratory exams showed severe anemia, thrombocytopenia, active urine sediments, and hypocomplementemia. Despite pulse steroid therapy, blood transfusions, intravenous immunoglobulin and aggressive resuscitative measures, she expired a day after hospital admission. Summary: These cases narrate instances of the onset or exacerbation of lupus following HPV immunization suggesting adjuvant-induced autoimmunity. On the other hand, there are reports of higher incidence of HPV infection in SLE, with the infection per se possibly contributing to disease activity. Thus, the benefit of HPV immunization may still outweigh the risk among these individuals.

Vaccine model of antiphospholipid syndrome induced by tetanus vaccine

Successful induction of antiphospholipid syndrome (APS) in two different non-autoimmune prone mouse strains, BALB/c and C57BL/6, was achieved by tetanus toxoid (TTd) hyperimmunization using different adjuvants (glycerol or aluminium hydroxide), and different adjuvant pretreatments (glycerol or Complete Freund’s Adjuvant (CFA)). APS had different manifestations of reproductive pathology in BALB/c and C57BL/6 mice: fetal resorption (as a consequence of extreme T-cell activation obtained in the course of pretreatment), and lowering of fecundity (as a consequence of polyclonal B-cell stimulation), respectively. In BALB/c mice fetal resorption coincided with glycerol and CFA pretreatments, while in C57BL/6 mice lowering of fecundity was most obvious in CFA-pretreated mice immunized with TTd in aluminium hydroxide. Both molecular mimicry and polyclonal B-cell activation occur in APS induction, with molecular mimicry effects being dominant in BALB/c mice, and polyclonal cell activation being dominant in C57BL/6 mice. Confirmation of molecular mimicry effects, which in the condition of T-cell stimulation generated fetal resorptions in the BALB/c strain, was achieved by passive infusion of monoclonal antibody (MoAb) T-26 specific for TTd and anti-β2-glycoprotein I obtained after TTd hyperimunization. High polyclonal B-cell activation in C57BL/6 mice prevented fetal resorption but induced fecundity lowering, as was the case in passive administration of MoAb T-26 in this mouse strain. Passive infusion of anti-idiotypic MoAb Y7 into C57BL/6 mice induced fetal resorptions and confirmed the above suggestion on the protective role of polyclonal B-cell stimulation in fetal resorptions.

Application of the immunological disease continuum to study autoimmune and other inflammatory events after vaccination

In vaccine safety monitoring, the evaluation of possible autoimmune events is challenging. Developing grouping systems based on pathophysiology, instead of organ systems, may enhance our ability to identify or verify associations between vaccines and adverse immunologically mediated events in clinical trials and post-licensure surveillance. Emerging data suggest that self-directed tissue inflammation occurs along a continuum from innate immune-driven diseases to adaptive immune-driven diseases. Herein, we develop this proposed classification for the vaccination setting in which inflammatory diseases are placed along a continuum according to the two major arms of the immune system, the innate immune arm (mediated by cells including neutrophils, macrophages and complement) and the adaptive immune arm (cell-mediated and humoral response). We incorporate hypersensitivity reactions and molecular mimicry vaccine-related reactions into this mechanistic scheme. We show how this could have important implications to assess mechanisms of potential immune-mediated adverse events following vaccination.