Ilan Krause

Bacterial induction of autoantibodies to β2-glycoprotein-I accounts for the infectious etiology of antiphospholipid syndrome

The antiphospholipid syndrome (APS) is characterized by the presence of pathogenic autoantibodies against beta2-glycoprotein-I (beta2GPI). The factors causing production of anti-beta2GPI remain unidentified, but an association with infectious agents has been reported. Recently, we identified a hexapeptide (TLRVYK) that is recognized specifically by a pathogenic anti-beta2GPI mAb. In the present study we evaluated the APS-related pathogenic potential of microbial pathogens carrying sequences related to this hexapeptide. Mice immunized with a panel of microbial preparations were studied for the development of anti-beta2GPI autoantibodies. IgG specific to the TLRVYK peptide were affinity purified from the immunized mice and passively infused intravenously into naive mice at day 0 of pregnancy. APS parameters were evaluated in the infused mice on day 15 of pregnancy. Following immunization, high titers of antipeptide [TLRVYK] anti-beta2GPI Abs were observed in mice immunized with Haemophilus influenzae, Neisseria gonorrhoeae, or tetanus toxoid. The specificity of binding to the corresponding target molecules was confirmed by competition and immunoblot assays. Naive mice infused with the affinity-purified antipeptide Abs had significant thrombocytopenia, prolonged activated partial thromboplastin time and elevated percentage of fetal loss, similar to a control group of mice immunized with a pathogenic anti-beta2GPI mAb. Our study establishes a mechanism of molecular mimicry in experimental APS, demonstrating that bacterial peptides homologous with beta2GPI induce pathogenic anti-beta2GPI Abs along with APS manifestations.

In vitro antiviral and antibacterial activity of commercial intravenous immunoglobulin preparations – a potential role for adjuvant intravenous immunoglobulin therapy in infectious diseases*

Summary The identification of specific antimicrobial activity of intravenous immunoglobulin (IVIG) preparations against particular microbial pathogens can assist in determining their therapeutic potential for specific infectious diseases. We analysed five different commercial IVIG preparations for the presence of antibodies directed against a large panel of viral, bacterial, fungal and parasitic pathogens. All IVIG batches contained high activity against herpesviruses types 1, 2, 6 and 7, as well as against varicella zoster virus, Epstein‐Barr virus (EBV), measles, mumps, rubella and parvovirus B19. Some IVIG batches also had a significant activity against adenovirus and Saint Louis encephalitis virus. The IVIGs held high activity against several bacterial pathogens, including Mycoplasma pneumonia, Chlamydia pneumonia, Helicobacter pylori and tetanus. No activity was found against various parasitic and fungal pathogens. Our findings may provide further support for the use of IVIG for the prevention and treatment of infections caused by specific viral and bacterial pathogens.

Induction of experimental anti-phospholipid syndrome associated with SLE following immunization with human monoclonal pathogenic anti-DNA idiotype

MIV-7 is a human monoclonal antibody that binds to DNA and carries a pathogenic anti-DNA idiotype 16/6. The antibody was generated by fusing peripheral blood lymphocytes of a healthy donor which were stimulated with an anti-idiotypic antibody to B11 (a human mAb anti-mouse mammary tumor virus-MMTV). The MIV-7, in addition to being an anti-DNA antibody, also binds to MMTV glycoproteins. Following immunization into the footpad of naive BALB/c mice with MIV-7, the mice developed anti-phospholipid syndrome (APLS) and SLE. The APLS was characterized by thrombocytopenia, the presence of anticardiolipin antibodies, lupus anticoagulant (prolonged APTT), high resorption rate of fetuses and lower mean weights of the placentae and fetuses. The SLE was characterized by serological markers (e.g. anti-DNA), laboratory (increased sedimentation rate and proteinuria) and histological findings (deposition of immune complexes in the glomeruli). Active immunization of mice with mouse monoclonal anti-cardiolipin antibodies led to the induction of primary APLS without SLE. The results add to our previous passive transfer model in which mouse monoclonal anti-cardiolipin antibody generated from immunized mice (CAM) was infused into the tail vein and also resulted in induction of pure APLS [11]. Our results demonstrate the ability to induce secondary APLS to SLE following immunization with a pathogenic idiotype of anti-DNA antibodies and to induce primary APLS with anti-cardiolipin mAb. The existence of these experimental models may permit controlled studies of novel therapeutic models.

Brief Report: Immune Factors in Autism: A Critical Review

Pervasive developmental disorders represent a group of neurodevelopmental disorders that affect children early in their development. Autistic disorder is the best described of these disorders, yet even this term covers a broad group of clinical presentations. Various immune system abnormalities, including autoimmunity and defects in different subsets of immune cells, have been reported in children with autistic disorder, suggesting that immune factors may play a role in the development of autism. Based on anecdotal observation, vaccination was proposed to cause autism in some children, but several controlled studies have failed to support this claim. Intravenous immunoglobulin infusions has been tested as immunotherapy for autism, although the preliminary results are inconclusive and there is a risk of potentially fatal transmission of blood-borne pathogens. To examine this issue, intensive well-controlled epidemiological and bench studies need to be carried out in defined and carefully controlled study subjects to establish the cellular and molecular basis of autism, against which the effects of each proposed immune factor can be examined.

The Effect of Aspirin on Recurrent Fetal Loss in Experimental Antiphospholipid Syndrome

PURPOSE: To evaluate the effect of aspirin treatment upon fetal loss in mice with experimental antiphospholipid syndrome (APLS).

Prevalence and clinical correlations of antibodies against six beta 2-glycoprotein-I-related peptides in the antiphospholipid syndrome

Two-hundred ninety five patients with the antiphospholipid syndrome (APS) were studied for the presence of antibodies against six anti-β2GPI-related peptides Abs. The prevalence of a wide spectrum of clinical and laboratory parameters of APS was evaluated in all patients, and correlated with the presence of each anti-β2GPI peptide antibody. The rates of the various antipeptides Abs ranged from 18.0 to 63.7%. Altogether, 87.1% of the patients had antibody reactivity against at least one of the six β2GPI-related peptides. A high degree of simultaneous reactivity against several β2GPI-peptides was found. Positive and negative correlations were found between several antipeptides Abs and the rates of thrombosis and fetal loss. Our results point to a heterogeneous activity of anti-phospholipid Abs in APS patients, directed, often concurrently, against various epitopes of the β2GPI molecule. Evaluation of APS patients for the presence of specific antipeptides Abs may be of a value in predicting the risk for future thrombotic and obstetrical complication, as well as for specific therapeutic purposes.

MONOCLONAL ANTI-ENDOTHELIAL CELL ANTIBODIES FROM A PATIENT WITH TAKAYASU ARTERITIS ACTIVATE ENDOTHELIAL CELLS FROM LARGE VESSELS

OBJECTIVE To create monoclonal anti-endothelial cell antibodies (mAECA) from a patient with Takayasu arteritis to evaluate their ability to activate human umbilical vein endothelial cells (HUVEC), and to characterize the mechanism of EC activation. METHODS A panel of mAECA was generated from peripheral blood lymphocytes of a patient with Takayasu arteritis, using Epstein-Barr virus transformation. Activity against macrovascular EC (HUVEC) and microvascular EC (human bone marrow EC immortalized by SV40) antigens was detected by enzyme-linked immunosorbent assay. Inhibition studies were used to select the monoclonal antibodies (mAECA) which share the same EC epitope binding specificity as the total IgG-AECA from the Takayasu arteritis patient. The binding of the mAECA to human aortic EC was studied by immunohistochemistry. The secretion levels of interleukin-6 (IL-6) and von Willebrand factor (vWF) were determined, to serve as markers for EC activation. The activated EC were examined for the adherence of a monocytic cell line (U937), as well as for expression of vascular cell adhesion molecule 1, intercellular adhesion molecule 1, and E-selectin. In addition, nuclear extracts of the mAECA-treated EC were analyzed for the induction of translocation of nuclear factor kappaB (NF-kappaB), using a specific NF-kappaB oligoprobe in an electrophoretic mobility shift assay. RESULTS Six mAECA were selected, the mixture of which produced 100% inhibition of binding of the original IgG (from the patient with Takayasu arteritis) to HUVEC. All mAECA possessed high activity against macrovascular EC, but none had significant antimicrovascular EC activity. The mAECA, but not normal human IgG, had anti-human aortic EC activity. Four of the 6 mAECA activated EC, manifested by increased IL-6 and vWF secretion. The 4 mAECA induced EC expression of adhesion molecules and increased adhesion of U937 monocytic cells to EC. In addition, these mAECA stimulated the nuclear translocation of the NF-kappaB transcription factor. CONCLUSION Our findings suggest that AECA may directly stimulate EC in Takayasu arteritis through elevation of adhesion molecule expression associated with NF-kappaB activation and adhesion of monocytes, and may therefore play a pathogenic role in the development of the vasculopathy in Takayasu arteritis.

Close association between valvar heart disease and central nervous system manifestations in the antiphospholipid syndrome

Background: Heart valves lesions and central nervous system involvement are among the most common manifestations of the antiphospholipid syndrome (APS). Objective: To evaluate possible interrelations between these manifestations in a large group of APS patients. Methods: 284 APS patients were evaluated retrospectively, 159 of whom had primary APS. Cardiac–CNS associations were determined for the entire study population, and for subgroups of patients with primary APS or APS associated with systemic lupus erythematosus (SLE). Results: Significant associations where found between cardiac vegetations and epilepsy (p<0.02), and between cardiac valve thickening or dysfunction and migraine (p = 0.002). Borderline association was found between valvar vegetations and migraine (p = 0.09). A significant association was also found between all valvar lesions and stroke or transient ischaemic attacks. Subanalyses showed that patients with primary APS had significant associations between cardiac valve pathology and all CNS manifestations, while patients with APS associated with SLE had no such associations. Conclusions: The study suggests potential differences in biological behaviour between primary APS and APS associated with SLE. The presence of cardiac valve pathology may be a risk factor for several types of CNS involvement in PAPS.

Prevalence and clinical aspects of Behcet's disease in the north of Israel.

Behcet’s disease (BD) has a higher prevalence in countries along the ancient silk route, but the actual prevalence in Israel is unknown. We evaluated the occurrence and clinical expression of BD in the northern region of Israel: in the whole population and by ethnic groups. The sample included all adult patients with BD (International Study Group criteria) treated at three medical centers in northern Israel. Patient data were collected by file review and physician survey. Relevant demographic data for the population served by the medical centers were obtained from the official Israeli authorities. A total of 112 patients were identified. The overall prevalence of BD was 15.2/100,000 and was similar in men and women. The prevalence rates among the Jewish, Arab, and Druze populations were 8.6, 26.2, and 146.4 per 100,000, respectively. Age at disease onset was similar in all ethnic groups and significantly lower in males (28.6±9.7 vs 32.9±11.3, p=0.03). There were no differences in disease manifestations by sex or ethnicity. All Druze patients were HLA-B5 positive, compared to 80.8% of the Arab patients and 72.0% of the Jewish patients. Recurrent oral ulcers in family members were more common in Arab patients (p=0.004). The BD severity index was significantly lower in Druze patients (p=0.05), mainly in males (p=0.03). This study confirms the high prevalence of BD in Israel and the variability in disease rates and expression by ethnic origin. Our findings, particularly regarding the Druze population, call for further field surveys and genetic studies.

IVIG for Autoimmune, Fibrosis, and Malignant Conditions: Our Experience with 200 Patients

Intravenous immunoglobulin (IVIG) is generated from the plasma of more than 10,000 healthy subjects. Originally IVIG was employed to supplement the missing Igs in subjects with immune-deficiencies. Later on it was given successfully to patients with autoimmune conditions, in some of which the benefits were confirmed by double blind studies (i.e. polymyositis), while in others remarkable case reports and series of patients have alluded to its beneficial effects. Especially when conventional therapies failed. Recently, due to multiple mechanisms, IVIG was found to be useful in reducing collagen deposition (i.e. scleroderma) and to prevent metastatic spread. When given properly (not more than 0.4 g/Kg. B.W. 5 day), side effects are minimal. Yet, its high price (>3,000 US