Anti-phospholipid antibodies following vaccination with recombinant hepatitis B vaccine

Vaccinomics and adversomics: key elements for a personalized vaccinology

Vaccines are one of the most important and effective tools in the prevention of infectious diseases and research about all the aspects of vaccinology are essential to increase the number of available vaccines more and more safe and effective. Despite the unquestionable value of vaccinations, vaccine hesitancy has spread worldwide compromising the success of vaccinations. Currently, the main purpose of vaccination campaigns is the immunization of whole populations with the same vaccine formulations and schedules for all individuals. A personalized vaccinology approach could improve modern vaccinology counteracting vaccine hesitancy and giving great benefits for human health. This ambitious purpose would be possible by facing and deepening the areas of vaccinomics and adversomics, two innovative areas of study investigating the role of a series of variables able to influence the immune response to vaccinations and the development of serious side effects, respectively. We reviewed the recent scientific knowledge about these innovative sciences focusing on genetic and non-genetic basis involved in the individual response to vaccines in terms of both immune response and side effects.

Antiphospholipid Antibodies Occurrence in Acute SARS-CoV-2 Infection without Overt Thrombosis

We sought to determine the prevalence of antiphospholipid antibodies (aPLs) and their correlation with COVID-19 severity (in terms of clinical and laboratory parameters) in patients without thrombotic events during the early phase of infection. This was a cross-sectional study with the inclusion of hospitalized COVID-19 patients from a single department during the COVID-19 pandemic (April 2020-May 2021). Previous known immune disease or thrombophilia along with long-term anticoagulation and patients with overt arterial or venous thrombosis during SARS-CoV-2 infection were excluded. In all cases, data on four criteria for aPL were collected, namely lupus anticoagulant (LA), IgM and IgG anticardiolipin antibodies (aCL), as well as IgG anti-β2 glycoprotein I antibodies (aβ2GPI). One hundred and seventy-nine COVID-19 patients were included, with a mean age of 59.6 (14.5) years and a sex ratio of 0.8 male: female. LA was positive in 41.9%, while it was strongly positive in 4.5%; aCL IgM was found in 9.5%, aCL IgG in 4.5%, and aβ2GPI IgG in 1.7% of the sera tested. Clinical correlation: LA was more frequently expressed in severe COVID-19 cases than in moderate or mild cases (p = 0.027). Laboratory correlation: In univariate analysis, LA levels were correlated with D-dimer (p = 0.016), aPTT (p = 0.001), ferritin (p = 0.012), C-reactive protein (CRP) (p = 0.027), lymphocyte (p = 0.040), and platelet (p < 0.001) counts. However, in the multivariate analysis, only the CRP levels correlated with LA positivity: OR (95% CI) 1.008 (1.001-1.016), p = 0.042. LA was the most common aPL identified in the acute phase of COVID-19 and was correlated with infection severity in patients without overt thrombosis.

Development of Autoantibodies Following BNT162b2 mRNA COVID-19 Vaccination and Their Association with Disease Flares in Adult Patients with Autoimmune Inflammatory Rheumatic Diseases (AIIRD) and the General Population: Results of 1-Year Prospective Follow-Up Study

Development of autoantibodies following BNT162b2 mRNA COVID-19 vaccination and their association with disease flares in adult patients with autoimmune inflammatory rheumatic diseases (AIIRD) and the general population: results of 1-year prospective follow-up study. We conducted a prospective study aimed at investigating the incidence of appearance of autoantibodies (antinuclear, antiphospholipid, and rheumatoid factor) in the sera of 463 adult patients with AIIRD compared to 55 controls from the general population prior to, and following the second and third vaccine doses, and at 1-year of follow-up. Pre- and post-vaccination disease activity indices and the association of autoantibodies with rheumatic disease flares and new onset AIIRD were examined. Autoantibody development of any type in AIIRD patients vs. the controls was 4.0% (vs. 6.7%, p = 0.423) following two vaccine doses and 7.6% (vs. 0%, p = 0.152) after three doses. There was no significant difference in sex, age, or disease-type among individuals with and without autoantibody development, regardless of the immunosuppressant use. More patients developed autoantibodies following the third than the second vaccine dose (p = 0.004). Disease flares occurred in 5.8% and 7.2% of AIIRD patients following second and third vaccine doses, respectively, with autoantibody production increasing the risk of flares following the second (p = 0.002) and third (p = 0.004) vaccine doses. BNT162b2 vaccination resulted in the development of autoantibodies in a minority of AIIRD patients and controls. Autoantibody development was associated with disease flares in patients, but no new-onset autoimmunity was observed.

Vaccines and Autoimmunity-From Side Effects to ASIA Syndrome

Since vaccines are in fact manufactured chemical compounds such as drugs, the appearance of side effects following their use is not surprising. Similarly, as the main goal of vaccines is to stimulate the immune system bringing out the production of protective antibodies, autoimmune-related side effects as a consequence of increased immune activity do not seem irrational. Fortunately, the rate of such side effects is low; however, the importance of reporting adverse events following vaccinations, understanding the mechanisms behind their appearance, making early diagnosis, and appropriate treatment cannot be overemphasized. In fact, autoimmune-related side effects of vaccines, particularly those based on adjuvants, were reported long before the introduction of the autoimmune/inflammatory syndrome induced by adjuvants (ASIA). Nevertheless, ASIA gathered and united the side effects of vaccines under one title, a step which helped organize the research and call for better immune stimulators than adjuvants. New technologies and methods of making vaccines were clearly noticed during the pandemic of COVID-19 after the introduction of mRNA-based vaccines. In our current paper, we introduce the notion of side effects to vaccines, particularly those of autoimmune nature, the mechanisms of ASIA, and the main vaccines linked with the syndrome including the recent COVID-19 vaccines. The transition from side effects to ASIA is the main idea behind our work.

Lupus, vaccinations and COVID-19: What we know now

Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), the virus causing Coronavirus disease 2019 (COVID-19), has had a huge impact on health services, with a high mortality associated with complications including pneumonia and acute respiratory distress syndrome. Patients with systemic lupus erythematosus (SLE) are at increased risk of viral infections, and recent data suggests they may be at an increased risk of poor outcomes with COVID-19. This may be particularly true for those on rituximab or high dose steroids. A huge international effort from the scientific community has so far resulted in the temporary authorisation of three vaccines which offer protection against SARS-CoV-2, with over 30 other vaccines being evaluated in ongoing trials. Although there has historically been concern that vaccines may trigger disease flares of SLE, there is little convincing evidence to show this. In general lupus patients appear to gain good protection from vaccination, although there may be reduced efficacy in those with high disease activity or those on immunosuppressive therapies, such as rituximab or high dose steroids. Recent concerns have been raised regarding rare clotting events with the AstraZeneca/Oxford vaccine and it is currently unknown whether this risk is higher for those patients with secondary antiphospholipid syndrome. With the possibility of annual COVID vaccination programmes in the future, prospective data collection and registries looking at the effect of vaccination on SLE disease control, the incidence of COVID-19 in SLE patients and severity of COVID-19 disease course would all be useful. As mass vaccination programmes begin to roll out across the world, we assess the evidence of the use of vaccines in SLE patients and in particular vaccines targeting SARS-CoV-2.

Vaccinomics and Adversomics in the Era of Precision Medicine: A Review Based on HBV, MMR, HPV, and COVID-19 Vaccines

Precision medicine approaches based on pharmacogenomics are now being successfully implemented to enable physicians to predict more efficient treatments and prevention strategies for a given disease based on the genetic background of the patient. This approach has already been proposed for vaccines, but research is lagging behind the needs of society, and precision medicine is far from being implemented here. While vaccinomics concerns the effectiveness of vaccines, adversomics concerns their side effects. This area has great potential to address public concerns about vaccine safety and to promote increased public confidence, higher vaccination rates, and fewer serious adverse events in genetically predisposed individuals. The aim here is to explore the contemporary scientific literature related to the vaccinomic and adversomic aspects of the three most-controversial vaccines: those against hepatitis B, against measles, mumps, and rubella, and against human Papilloma virus. We provide detailed information on the genes that encode human leukocyte antigen, cytokines and their receptors, and transcription factors and regulators associated with the efficacy and safety of the Hepatitis B and Measles, Mumps and Rubella virus vaccines. We also investigate the future prospects of vaccinomics and adversomics of a COVID-19 vaccine, which might represent the fastest development of a vaccine ever.

Environmental Triggers of Autoreactive Responses: Induction of Antiphospholipid Antibody Formation

Antiphospholipid antibodies (aPLs) comprise a diverse family of autoantibodies targeted against proteins with the affinity toward negatively charged phospholipids or protein-phospholipid complexes. Their clinical significance, including prothrombotic potential of anti-cardiolipin antibodies (aCLs), anti-β2-glycoprotein I antibodies (aβ2-GPIs), and lupus anti-coagulant (LA), is well-established. However, the ontogeny of these pathogenic aPLs remains less clear. While transient appearance of aPLs could be induced by various environmental factors, in genetically predisposed individuals these factors may eventually lead to the development of the antiphospholipid syndrome (APS). Since the first description of APS, it has been found that a wide variety of microbial and viral agents influence aPLs production and contribute to clinical manifestations of APS. Many theories attempted to explain the pathogenic potential of different environmental factors as well as a phenomenon termed molecular mimicry between β2-GPI molecule and infection-relevant structures. In this review, we summarize and critically assess the pathogenic and non-pathogenic formation of aPLs and its contribution to the development of APS.

Chimpanzee Adenovirus Vector Ebola Vaccine

BACKGROUND

The unprecedented 2014 epidemic of Ebola virus disease (EVD) prompted an international response to accelerate the availability of a preventive vaccine. A replication-defective recombinant chimpanzee adenovirus type 3-vectored ebolavirus vaccine (cAd3-EBO), encoding the glycoprotein from Zaire and Sudan species, that offers protection in the nonhuman primate model, was rapidly advanced into phase 1 clinical evaluation.

METHODS

We conducted a phase 1, dose-escalation, open-label trial of cAd3-EBO. Twenty healthy adults, in sequentially enrolled groups of 10 each, received vaccination intramuscularly in doses of 2×10¹⁰ particle units or 2×10¹¹ particle units. Primary and secondary end points related to safety and immunogenicity were assessed throughout the first 8 weeks after vaccination; in addition, longer-term vaccine durability was assessed at 48 weeks after vaccination.

RESULTS

In this small study, no safety concerns were identified; however, transient fever developed within 1 day after vaccination in two participants who had received the 2×10¹¹ particle-unit dose. Glycoprotein-specific antibodies were induced in all 20 participants; the titers were of greater magnitude in the group that received the 2×10¹¹ particle-unit dose than in the group that received the 2×10¹⁰ particle-unit dose (geometric mean titer against the Zaire antigen at week 4, 2037 vs. 331; P=0.001). Glycoprotein-specific T-cell responses were more frequent among those who received the 2×10¹¹ particle-unit dose than among those who received the 2×10¹⁰ particle-unit dose, with a CD4 response in 10 of 10 participants versus 3 of 10 participants (P=0.004) and a CD8 response in 7 of 10 participants versus 2 of 10 participants (P=0.07) at week 4. Assessment of the durability of the antibody response showed that titers remained high at week 48, with the highest titers in those who received the 2×10¹¹ particle-unit dose.

CONCLUSIONS

Reactogenicity and immune responses to cAd3-EBO vaccine were dose-dependent. At the 2×10¹¹ particle-unit dose, glycoprotein Zaire-specific antibody responses were in the range reported to be associated with vaccine-induced protective immunity in challenge studies involving nonhuman primates, and responses were sustained to week 48. Phase 2 studies and efficacy trials assessing cAd3-EBO are in progress. (Funded by the Intramural Research Program of the National Institutes of Health; VRC 207 ClinicalTrials.gov number, NCT02231866 .).

The environment and antiphospholipid syndrome

The etiology of autoimmune diseases is multifactorial. The degree to which genetic and environmental factors influence susceptibility to autoimmune diseases is poorly defined. It is believed that versatile clinical presentations of autoimmune diseases stem from various combinations of the genetic and environmental factors. One of the newly diagnosed autoimmune diseases is the antiphospholipid syndrome (APS). APS is characterized by vascular thrombosis, and/or pregnancy morbidity associated with anticardiolipin (aCL), anti-β2-glycoprotein-I (anti-β2GPI) and lupus anticoagulant (LAC).

Pediatric antiphospholipid syndrome

Antiphospholipid syndrome (APS) is a multisystem autoimmune condition characterized by vascular thromboses associated with persistently positive antiphospholipid antibodies. There is currently a paucity of data (incidence, prevalence, thrombosis risk, and effective treatment) in pediatric APS. The purpose of this report is to review the current literature on APS in children and neonates, identify the gaps in current knowledge, and suggest avenues for studies to fill those gaps.

Vaccines, adjuvants and autoimmunity

Vaccines and autoimmunity are linked fields. Vaccine efficacy is based on whether host immune response against an antigen can elicit a memory T-cell response over time. Although the described side effects thus far have been mostly transient and acute, vaccines are able to elicit the immune system towards an autoimmune reaction. The diagnosis of a definite autoimmune disease and the occurrence of fatal outcome post-vaccination have been less frequently reported. Since vaccines are given to previously healthy hosts, who may have never developed the disease had they not been immunized, adverse events should be carefully accessed and evaluated even if they represent a limited number of occurrences. In this review of the literature, there is evidence of vaccine-induced autoimmunity and adjuvant-induced autoimmunity in both experimental models as well as human patients. Adjuvants and infectious agents may exert their immune-enhancing effects through various functional activities, encompassed by the adjuvant effect. These mechanisms are shared by different conditions triggered by adjuvants leading to the autoimmune/inflammatory syndrome induced by adjuvants (ASIA syndrome). In conclusion, there are several case reports of autoimmune diseases following vaccines, however, due to the limited number of cases, the different classifications of symptoms and the long latency period of the diseases, every attempt for an epidemiological study has so far failed to deliver a connection. Despite this, efforts to unveil the connection between the triggering of the immune system by adjuvants and the development of autoimmune conditions should be undertaken. Vaccinomics is a field that may bring to light novel customized, personalized treatment approaches in the future.

Pathogenetic mechanisms of antiphospholipid antibody production in antiphospholipid syndrome

Antiphospholiipid syndrome (APS) is an autoimmune disease characterized by the pathological action of antiphospholipid antibodies (aPL), that leads to recurrent pregnancy loss and thrombosis. Despite limited evidence, it is clear that there are both inherited and acquired components of the ontogeny of these antibodies. Animal genetic studies and human familial and population studies highlight the influence of genetic factors in APS, particularly human leukocyte antigen associations. Similarly, both animal and human studies have reported the importance of acquired factors in APS development and infectious agents in particular have a great impact on aPL production. Bacterial and viral agents have been implicated in the induction of autoimmune responses by various mechanisms including molecular mimicry, cryptic autoantigens exposure and apoptosis. In this review we highlight the latest updates with regards to inherited and acquired factors leading to the manufacturing of pathogenic antibodies and APS.

Pandemic influenza immunization in primary antiphospholipid syndrome (PAPS): a trigger to thrombosis and autoantibody production?

OBJECTIVE

The objective of this report is to conduct short- and long-term evaluation of a large panel of antiphospholipid (aPL) autoantibodies following pandemic influenza A/H1N1 non-adjuvant vaccine in primary antiphospholipid syndrome (PAPS) patients and healthy controls.

METHODS

Forty-five PAPS and 33 healthy controls were immunized with H1N1 vaccine. They were prospectively assessed at pre-vaccination, and three weeks and six months after vaccination. aPL autoantibodies were determined by an enzyme-linked immunosorbent assay (ELISA) and included IgG/IgM: anticardiolipin (aCL), anti-beta2glycoprotein I (anti-β2GPI); anti-annexin V, anti-phosphatidyl serine and anti-prothrombin antibodies. Anti-Sm was determined by ELISA and anti-double-stranded DNA (anti-dsDNA) by indirect immunofluorescence. Arterial and venous thrombosis were also clinically assessed.

RESULTS

Pre-vaccination frequency of at least one aPL antibody was significantly higher in PAPS patients versus controls (58% vs. 24%, p = 0.0052). The overall frequencies of aPL antibody at pre-vaccination, and three weeks and six months after immunization remained unchanged in patients (p = 0.89) and controls (p = 0.83). The frequency of each antibody specificity for patients and controls remained stable in the three evaluated periods (p > 0.05). At three weeks, two PAPS patients developed a new but transient aPL antibody (aCL IgG and IgM), whereas at six months new aPL antibodies were observed in six PAPS patients and none had high titer. Anti-Sm and anti-dsDNA autoantibodies were uniformly negative and no new arterial or venous thrombosis were observed throughout the study.

CONCLUSIONS

This is the first study to demonstrate that pandemic influenza vaccine in PAPS patients does not trigger short- and long-term thrombosis or a significant production of aPL-related antibodies (ClinicalTrials.gov, #NCT01151644).

The role of B lymphocytes in the progression from autoimmunity to autoimmune disease

Autoimmunity, defined as the presence of autoreactive T and/or B lymphocytes in the periphery, is a frequent and probably even physiological condition. It is mainly caused by the fact that the central tolerance mechanisms, which are responsible for counter-selection of autoreactive lymphocytes, are not perfect and thus a limited number of these autoreactive cells can mature and enter the periphery. Nonetheless, autoreactive cells do not lead automatically to autoimmune disease as evidenced by a multitude of experimental and human data sets. Interestingly, the progression from autoimmunity to autoimmune disease is not only determined by the degree of central tolerance leakage and thus the amount of autoreactive lymphocytes in the periphery, but also by peripheral mechanism of activation and control of the autoreactive cells. In this review, we discuss the contribution of peripheral B lymphocytes in this process, ranging from activation of T cells and epitope spreading to control of the autoimmune process by regulatory mechanisms. We also discuss the parallels with the role of B cells in the induction and control of alloimmunity in the context of organ transplantation, as more precise knowledge of the pathogenic antigens and time of initiation of the immune response in allo- versus auto-immunity allows better dissection of the exact role of B cells. Since peripheral mechanisms may be easier to modulate than central tolerance, a more thorough understanding of the role of peripheral B cells in the progression from autoimmunity to autoimmune disease may open new avenues for treatment and prevention of autoimmune disorders.

When APS (Hughes syndrome) met the autoimmune/inflammatory syndrome induced by adjuvants (ASIA)

Vaccination of healthy individuals is the most effective approach to protect the public from infections and prevent the spread of many infectious diseases all over the globe. Licensed vaccines are mostly safe, but in rare cases they may be associated with humoral response to self-antigens due to molecular mimicry, epitope spread, bystander activation or polyclonal triggering. Moreover, the clinical picture of autoimmune conditions following post-vaccination is rarer. Nevertheless, anecdotal case reports on the flare of autoimmune response with clinical manifestations were reported. Herein, we discuss this topic in relation to post-vaccination-induced antiphospholipid antibodies following tetanus toxoid vaccine, HBV and influenza associated in rare cases with antiphospholipid syndrome clinical manifestations. We will discuss the possible mechanisms which pertain to ASIA (Shoenfeld syndrome).

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.

HIV-1 gp120 vaccine induces affinity maturation in both new and persistent antibody clonal lineages

Most antibodies that broadly neutralize HIV-1 are highly somatically mutated in antibody clonal lineages that persist over time. Here, we describe the analysis of human antibodies induced during an HIV-1 vaccine trial (GSK PRO HIV-002) that used the clade B envelope (Env) gp120 of clone W6.1D (gp120(W6.1D)). Using dual-color antigen-specific sorting, we isolated Env-specific human monoclonal antibodies (MAbs) and studied the clonal persistence of antibodies in the setting of HIV-1 Env vaccination. We found evidence of V(H) somatic mutation induced by the vaccine but only to a modest level (3.8% ± 0.5%; range 0 to 8.2%). Analysis of 34 HIV-1-reactive MAbs recovered over four immunizations revealed evidence of both sequential recruitment of naïve B cells and restimulation of previously recruited memory B cells. These recombinant antibodies recapitulated the anti-HIV-1 activity of participant serum including pseudovirus neutralization and antibody-dependent cell-mediated cytotoxicity (ADCC). One antibody (3491) demonstrated a change in specificity following somatic mutation with binding of the inferred unmutated ancestor to a linear C2 peptide while the mutated antibody reacted only with a conformational epitope in gp120 Env. Thus, gp120(W6.1D) was strongly immunogenic but over four immunizations induced levels of affinity maturation below that of broadly neutralizing MAbs. Improved vaccination strategies will be needed to drive persistent stimulation of antibody clonal lineages to induce affinity maturation that results in highly mutated HIV-1 Env-reactive antibodies.

Influenza vaccination can induce new-onset anticardiolipins but not β2-glycoprotein-I antibodies among patients with systemic lupus erythematosus

BACKGROUND

Antiphospholipid syndrome is characterized by autoantibodies against cardiolipins (aCL), lupus anticoagulant, and independent β2-glycoprotein (β2GPI). Controversy exists as to whether vaccination triggers the development of antiphospholipid antibodies (aPL) in patients with systemic lupus erythematosus (SLE).

METHODS

Patients with SLE (101) and matched controls (101) were enrolled from 2005-2009 and received seasonal influenza vaccinations. Sera were tested by ELISA for aCL at baseline, 2, 6, and 12 weeks after vaccination. Vaccine responses were ranked according to an overall anti-influenza antibody response index. Individuals with positive aCL were further tested for β2GPI antibodies.

RESULTS

Patients with SLE and healthy controls can develop new-onset aCL post vaccination, although at rates which do not differ between patients and controls (12/101 cases and 7/101 controls, OR 1.81, p = 0.34). New-onset moderate aCL are slightly enriched in African American SLE patients (5/36 cases; p = 0.094). The optical density measurements for aCL reactivity in patients were significantly higher than baseline at 2 weeks (p < 0.05), 6 weeks (p < 0.05), and 12 weeks (p < 0.05) post vaccination. No new β2GPI antibodies were detected among patients with new aCL reactivity. Vaccine response was not different between patients with and without new-onset aCL reactivity (p = 0.43).

CONCLUSIONS

This study shows transient increases in aCL, but not anti-β2GPI responses, after influenza vaccination.

In vivo study of hepatitis B vaccine effects on inflammation and metabolism gene expression

Pharmaceutical companies usually perform safety testing of vaccines, but all requirements of the World Health Organization and drug pharmacopoeias depend on general toxicity testing, and the gene expression study of hepatitis B vaccine is not done routinely to test vaccine quality. In this study, we applied a new technique of gene expression analysis to detect the inflammation and metabolism genes that might be affected by hepatitis B vaccine in mouse liver. Mice were used and divided into three groups: the first and second groups were treated with one or two human doses of vaccine, respectively, and the third group was used as a control. A microarray test showed that expression of 144 genes in the liver was significantly changed after 1 day of vaccination. Seven of these genes, which were related to inflammation and metabolism, were chosen and confirmed by quantitative real-time reverse transcription polymerase chain reaction (qRT-PCR) at 1, 4 and 7 days. The expression level of these genes can be considered as a biomarker for the effects of the vaccine.

Antigen-specific enhancement of natural human IgG antibodies to phosphatidylcholine, phosphatidylglycerol, phosphatidylinositol-4-phosphate, cholesterol, and lipid A by a liposomal vaccine containing lipid A

Natural IgG antibodies (NA) to lipids are ubiquitously distributed in sera of healthy humans and are believed to serve beneficial functions. Although NA to lipids generally exhibit germ line or near germ line binding specificities, the antibodies commonly increase transiently in the acute phases of most, if not all, infectious diseases and may serve as a first line of defense. In order to determine whether similar anti-lipid antibodies can be induced by a vaccine in humans, we examined stored sera obtained from volunteers who had previously received a candidate vaccine to Plasmodium falciparum. The vaccine had consisted of liposomes that contained both the recombinant protein antigen and also contained monophosphoryl lipid A (MPLA) as an adjuvant. All of the pre-immune sera contained NA to one or more of the liposomal lipids in the vaccine: dimyristol phosphatidylcholine (DMPC), dimyristoyl phosphatidylglycerol (DMPG), cholesterol, and MPLA. After initial immunization, followed by a boost, increased levels of IgG antibodies to all of the liposomal lipids, especially DMPG and MPLA, were observed by ELISA. Antibodies to phosphatidylinositol-4-phosphate (PIP) above the normal pre-immune NA to PIP were also observed. Although PIP was not present in the immunizing liposomes, based on the adsorption of anti-PIP antibodies by DMPG the anti-PIP antibodies were thought to represent cross-reacting anti-DMPG antibodies. The immune response was apparently antigen-specific in that NA to unrelated lipids, other than PIP, that were not present in the liposomes, galactosyl ceramide and ganglioside GM1, were not increased by the immunization. We conclude that antibodies to DMPC, DMPG, PIP, cholesterol, and MPLA can be induced in humans by immunization with liposomes containing MPLA.

Pathophysiology of the antiphospholipid antibody syndrome

Antiphospholipid antibodies (aPL) are associated with the recurrent pregnancy loss and thrombosis that characterizes the antiphospholipid antibody syndrome (APS). Although the ontogeny of these pathogenic antibodies has not been fully elucidated, there is evidence that indicates the involvement of both genetic and environmental factors. The ability of aPL to induce a procoagulant phenotype in APS patients plays a central role in the development of arterial and venous thrombotic manifestations typical of the disease. Inflammation serves as a necessary link between this procoagulant phenotype and actual thrombus development and is an important mediator of the placental injury seen in APS patients with obstetric complications. Recent evidence has indicated a role for abnormal cellular proliferation and differentiation in the pathophysiology of APS, especially in those patients with pregnancy morbidity and other more atypical manifestations that have no identifiable thrombotic cause. The interplay of genetic and environmental factors responsible for aPL development and the mechanisms by which these antibodies produce disease in APS patients is the focus of this review.

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.

Anti-influenza vaccination in systemic lupus erythematosus patients: an analysis of specific humoral response and vaccination safety

The objective of this study is to evaluate efficacy and safety of influenza vaccine in systemic lupus erythematosus (SLE) patients. We studied SLE patients and healthy subjects immunised with inactivated influenza vaccine. Efficacy was measured by comparing humoral response to vaccine antigens between groups. Safety was monitored by SLEDAI and serological markers. Subjects attended visits at baseline and on post-vaccination weeks 4 and 12. We enrolled 62 SLE patients and 47 healthy subjects. In post-immunisation week 4, anti-haemagglutinin antibody titres rose in the patient group at least 6.23-fold, compared to 11.90-fold among controls (P < or = 0.05). The seroconversion rate range was 53-56% among patients and 72-85% among controls (P < 0.05 for strains H1N1 and H3N2, NS for strain type B). The seroprotection rate ranged between 62% and 73% and between 90% and 98% in the patient and control group, respectively (P < 0.05). In post-vaccination week 12, the antibody titre was higher at least 3.86-fold in the patient group and 7.65-fold among controls. The seroconversion rate range was 32-40% among patients and 64-70% among controls, while the seroprotection rate ranged between 43% and 50% and between 79% and 94%, respectively (P < 0.005 for three strains). We identified one severe and six mild to moderate SLE exacerbations by week 12. The anti-nuclear antibodies and anti-double-stranded DNA titres grew by post-immunisation week 4 (P < 0.05). The post-vaccination response was weaker in SLE patients compared to healthy subjects. Immunisation did not change underlying disease activity.

Vaccination of healthy subjects and autoantibodies: from mice through dogs to humans

Vaccination against pathogenic microorganisms is one of the major achievements of modern medicine, but due to an increasing number of reports of adverse reactions the vaccination procedure has induced also considerable debate. It is well known that certain infections are involved in triggering the production of autoantibodies, which could lead to autoimmune adverse reactions in genetically predisposed subjects. Based on these findings it was assumed that vaccinations might induce similar autoimmune reactions. At present there is no clear-cut evidence that vaccinations are associated with overt autoimmune diseases but it has been demonstrated that in genetically predisposed persons vaccination can trigger the production of autoantibodies and autoimmune adverse reactions. The first studies investigating the production of autoantibodies following vacination were done in dogs and mice. Several studies investigated the production of autoantibodies following vaccination in patients with autoimmune diseases, but there are only limited data on the autoimmune responses after vaccinations in apparently healthy humans. This review summarizes current evidence on the vaccinationinduced autoantibodies in apparently healthy subjects including studies in animals and humans.

Autoimmune response following annual influenza vaccination in 92 apparently healthy adults

OBJECTIVE

To evaluate the possibility of autoimmune responses following annual influenza vaccination in a large cohort of apparently healthy adults.

METHODS

Autoantibodies including antinuclear antibodies (ANA), anticardiolipin antibodies (aCL), anti-beta(2)-glycoprotein I antibodies (anti-beta(2)-GPI), lupus anticoagulant (LA) and anti-extractable nuclear antigen antibodies (anti-ENA) were determined in 92 healthy adult subjects, staff at the University Children's Hospital Ljubljana. Blood samples were taken from each participant before the vaccination, 1 month and 6 months after the annual influenza vaccination.

RESULTS

Before the influenza vaccination, 26% of participants were positive for ANA, 16% for aCL, 7% for anti-beta(2)-GPI, 2% for LA and 1% for anti-ENA. There were no statistically significant differences in the percentage of positive ANA, aCL, anti-beta(2)-GPI, LA and anti-ENA before, 1 month and 6 months after the vaccination. One month after the vaccination 24% of participants demonstrated changes in the levels of autoantibodies including 15% of participants with increased level of autoantibodies or appearance of new autoantibodies. Six months after the vaccination 26% of participants demonstrated changes in the levels of autoantibodies including 13% of participants with increased level of autoantibodies or appearance of new autoantibodies. Persistently elevated levels of autoantibodies were observed in 7 (8%) participants and 2 showed progressively increased levels of IgM aCL or IgA anti-beta(2)-GPI, respectively. Eleven participants had a transient increase in autoantibodies.

DISCUSSION

Influenza vaccination in general did not alter the percentage of healthy adults with positive autoantibodies. Transiently or persistently increased levels of autoantibodies or appearance of new autoantibodies was demonstrated in up to 15% of apparently healthy adults after the influenza vaccination.

Neonatal effects of maternal antiphospholipid syndrome

Antiphospholipid antibodies (aPL) can impair the physiologic development of a fetus during pregnancy not only by causing thrombosis of the placental vessels, but also by directly binding throphoblast cells and modifying their functions. Consequently, the presence of aPL in pregnant women is linked to an increased rate of pregnancy complications. These include recurrent early miscarriages, late fetal losses, and hypertensive disorders of gestation. In this clinical setting, preeclampsia is usually early and severe and can be complicated by the syndrome of hemolysis, elevated liver enzymes, and low platelet count (HELLP syndrome). The close association between aPL and obstetric pathology supports the inclusion of these manifestations in the clinical classification criteria of antiphospholipid syndrome. About 30% of children born to mothers with aPL passively acquire these autoantibodies; fortunately, the occurrence of thrombosis seems extremely rare in these babies. The prospective ongoing studies of children born to antiphospholipid syndrome patients reassure us about their general good health; however, some data suggest that learning difficulties might occur, possibly related to in utero exposure to aPL.

Pharmacotherapy of chronic viral hepatitis and hepatocellular carcinoma

BACKGROUND

Hepatitis B virus (HBV) is a major etiologic agent of chronic liver disease (CLD) and hepatocellular carcinoma. Drugs have been developed and shown to be effective against HBV replication. These treatments are often associated with the resolution of CLD. However, they are too expensive, not well tolerated, and result in the development of resistance when given as mono or salvage therapies. In addition, most of these drugs target only the virus polymerase.

OBJECTIVE

To revitalize the field, drugs with other targets and combination therapies need to be developed.

METHODS

Major advances in HBV and liver cancer drug development over the past decade, focusing on Phase III trials and FDA-approved compounds, are presented.

RESULTS/DISCUSSION

A number of potent nucleoside/nucleotide analogs are now available for treatment, but for the long-term management of CLD, the development of combination therapies will probably be required. Development of compounds with new virus targets will enhance the utility of combination therapies. Development of compounds to host targets altered prior to or after the development of liver cancer, as demonstrated by sorafenib, need to be developed. The goal is to devise drug cocktails that will yield sustained virus responses and halt disease progression and tumor development.

Antiphospholipid syndrome (APS): where does it come from?

The antiphospholipid syndrome (APS) is the most common acquired thrombophilia. It is characterized by venous and arterial thrombosis, recurrent pregnancy loss, and various other clinical manifestations in the presence of antiphospholipid antibodies (aPL). Like other autoimmune diseases, the etiology of APS derives from a combination of genetic and environmental factors. The most significant environmental factors in APS are infectious agents, followed by trauma and drugs. Infections can induce aPL and, in the catastrophic variant of APS, about one-third of cases are associated with a clear recent infection. On their formation, aPL have been clearly shown to be pathogenic, because they influence all arms of the coagulation system and because passive transfer and active immunization protocols have demonstrated. Therefore, in a genetically susceptible individual, exposure to one or more infectious agent can cause a molecular mimicry and result in the production of pathogenic aPL that can induce thrombosis and pregnancy loss. Identification of the epitopes within the beta-2-glycoprotein-I molecule that serves as the target for autoantibodies makes them the target for immunomodulation of the syndrome.

Antiphospholipid antibodies in pediatric systemic lupus erythematosus and the antiphospholipid syndrome

The antiphospholipid syndrome (APS) is recognized increasingly as the most common acquired hypercoagulation state of autoimmune etiology and may occur as an isolated clinical entity (primary APS) or in association with an underlying systemic disease, particularly systemic lupus erythematosus (SLE). The major differences between pediatric and adult APS include absence of common acquired risk factors for thrombosis, absence of pregnancy-related morbidity, increased incidence of infection-induced antibodies, differences in cut-off values for determination of aPL and specific factors regarding long-term therapy in children. APS in children has been largely reported in patients with arterial or venous thromboses and less frequently in association with neurological or hematological manifestations. The presence of aPL in pediatric SLE can modify the disease expression and may be an important predictor of the development of irreversible organ damage. Two recently established international registries of neonates and children with APS provide a good opportunity to conduct large, prospective studies on the clinical significance of aPL and long-term outcome of pediatric APS.

HBV vaccine and dermatomyositis: is there an association?

The etiology of dermatomyositis is unknown, but immune mechanisms play an important role. Several dermatological manifestations have been reported among carriers of hepatitis B surface antigen, and after vaccination with the HBV vaccine. Almost all the skin reactions described were peculiar skin eruptions suggestive of an immune complex reaction. Some authors described the occurrence of dermatomyositis after BCG and influenza vaccination. We report a case of a 6-year-old child, who was vaccinated for hepatitis B virus and developed a flu-like disease accompanied by a skin rash, which had the typical features of dermatomyositis. The association of vaccination with autoimmunity is discussed.

Antiphospholipid antibodies in response to infection

An association between infections and antiphospholipid antibodies (aPL) has been reported in several epidemiologic and experimental studies. Infection-induced aPL have been traditionally regarded as transient and were generally not associated with clinical features of antiphospholipid syndrome. The distinction between autoimmune and postinfectious aPL on the basis of requirement of binding cofactor is not absolute, and in recent years, several reports demonstrated that some patients can produce pathogenic antibodies in response to infection. Infections most frequently associated with antiphospholipid syndrome include parvovirus B19, cytomegalovirus, varicella-zoster virus, HIV, streptococcal and staphylococcal infections, gram-negative bacteria, and Mycoplasma pneumoniae.

Strategies for selective priming of memory B cells

Long-term humoral immunity elicited by pathogens and vaccines alike relies upon the generation of both memory B cells (B(mem)) and long-lived plasma cells (PCs). Virtually all vaccine formulations induce the concomitant emergence of both B(mem) and PCs, suggesting that the emergence of these two differentiated B cells subsets is commonly controlled. Evidence presented shows specific Toll-like receptor (TLR) agonists coupled with soluble protein antigen (sAg) can selectively induce the expansion of antigen specific B(mem) in the absence of PC generation. The co-administration of either TLR 3 or 9 agonists with sAg induced germinal centre (GC) formation, antigen-specific B(mem), but failed to substantively induce the generation of long-lived bone marrow (BM) PCs. Upon re-challenge, high levels of PCs were induced with concomitant high titres of antigen-specific serum IgG. Hence, vaccines can be developed that can prime and protect the host to subsequent infectious agents without initial, high levels of antibody production. Furthermore, these studies suggest that the signals that govern the expansion and differentiation of B(mem) can be uncoupled from those that induce long-lived BM PCs.