High Levels Of IgG Antibodies Research Articles

IgG response to different stage-specific antigens of Mycobacterium tuberculosis

IgG response to different stage-specific antigens of Mycobacterium tuberculosis

Reaction of Monoclonal and Polyclonal Antibodies Made against Infectious Agents with Various Food Antigens

Background: During the past 10 years in our clinical immunology laboratory, we have observed that some patients with high titers of antibodies against the Herpes family of viruses also exhibit elevation in antibodies against Borrelia burgdorferi antigens. Furthermore, when sera from patients with high IgG antibody levels against B. burgdorferi and Epstein-Barr virus were tested for food-specific antibodies, the degree of immune reactivity to food antigens was much higher in patients who were seropositive for B. burgdorferi and EBV antigens than in those who were seronegative. We purchased monoclonal and affinity-purified polyclonal antibodies against B. burgdorferi, Herpes family viruses and other infectious agents, and reacted them with 180 different food antigens so we could examine the degree of cross-reactivity between infectious agents and various food antigens. Methods: Using ELISA methodology, we applied monoclonal and affinity-purified polyclonal antibodies against Epstein-Barr virus, cytomegalovirus, measles, rubella, herpes simplex type 1, Varicella zoster, Chlamydia pneumoniae, streptokinase, Yersinia enterocolitica and Borrelia burgdorferi, to 180 different food antigens in order to explain some baffling test results detected during lab testing. Results: While some of these antibodies did not react to any of the tested food antigens, B. burgdorferi antibody reacted with 39 foods, EBV-VCA antibody with 20, EBNA-1 antibody with 10, EBV-EA antibody with 20, rotavirus antibody with 11, and measles antibody with 4 out of 180 food antigens. We demonstrated that these antibodyantigen reactions are specific, since only specific antigens and not non-specific antigens inhibited these immune reactivities. Conclusions: Results indicate that the presence of some of the antibodies against infectious agents detected in human serum can result in false-positivity in serologic tests for food antigens used in the diagnosis of food adverse reactions. These results may explain antibody detection in the sera of many individuals against various food antigens that they have never actually eaten.

A Murine Model of Asparaginase Allergy

In order to study interventions that influence the severity of symptoms and serum asparaginase activity following asparaginase-induced hypersensitivity reactions, we developed a murine model of asparaginase allergy that recapitulates key features of clinical hypersensitivity to native E. coli asparaginase. BALB/c mice received 10 μg ip doses of E. coli asparaginase formulated with aluminum hydroxide adjuvant on day 0 and 14 of treatment in order to sensitize mice to asparaginase. Asparaginase allergies were induced in sensitized mice by challenging with a 100 μg iv dose of E. coli asparaginase on day 24 of treatment. The severity of hypersensitivity was reflected by the decrease in rectal temperature following the asparaginase challenge. Pre-challenge plasma samples were collected for anti-asparaginase antibody levels before inducing asparaginase allergies, and post-challenge samples were collected at the end of the experiment for measuring anti-asparaginase antibody levels, asparaginase activity, and mouse mast cell protease 1 (mMCP-1) levels.Sensitized mice developed high levels of anti-asparaginase IgG antibodies (P = 1.1 x 10-7) and had immediate hypersensitivity reactions (P = 3.3 x 10-10) to asparaginase upon challenge compared to non-sensitized mice. Furthermore, sensitized mice had profoundly lower plasma asparaginase activity (P = 4.2 x 10-13) and elevated levels of mouse mast cell protease 1 (mMCP-1, P = 6.1 x 10-3) after the asparaginase challenge compared to non-sensitized mice.We investigated the influence of pretreatment with the H1 receptor antagonist triprolidine, the H2 receptor antagonist cimetidine, the PAF receptor antagonist CV-6209, or dexamethasone on the severity of asparaginase-induced allergies. Our studies showed that the combination of triprolidine and CV-6209 was best for mitigating asparaginase-induced hypersensitivity symptoms (i.e., temperature drop) compared to non-pretreated, sensitized mice (P = 1.2 x 10-5). However, pretreatment with oral dexamethasone (4 mg/L in drinking water starting 7 days before asparaginase sensitization) was the only agent capable of mitigating the severity of the hypersensitivity symptoms (P = 0.03) and also partially restoring asparaginase activity (P = 8.3 x 10-4) compared to sensitized mice.Dose adjustment strategies were investigated for rescuing asparaginase activity in sensitized mice without requiring pretreatment with dexamethasone, and a 5-fold greater dose of asparaginase was required to restore enzyme activity to a similar concentration as in non-sensitized mice. In the absence of pretreatment, we found that the severity of asparaginase-induced reactions increased in a dose-dependent manner and that mMCP-1 levels correlated to the severity of the reactions (R2 = 0.577, P = 3.0 x 10-16).Our results suggest a role of histamine and PAF in asparaginase-induced allergies and demonstrate possible strategies for mitigating the severity of asparaginase-induced reactions and maintaining targeted concentrations of asparaginase. Furthermore, our results indicate that mast cell-derived proteases released during allergic reactions to asparaginase may be a useful marker of hypersensitivity, as elevated levels of mMCP-1 were detected in all sensitized mice and correlated with the severity of the reaction. DisclosuresEvans:St. Jude: In accordance with institutional policy (St. Jude), I and/or my spouse have in the past received a portion of the income St. Jude receives from licensing patent rights related to TPMT polymorphisms as clinical diagnostics. Patents & Royalties. Relling:St. Jude: In accordance with institutional policy (St. Jude), I and/or my spouse have in the past received a portion of the income St. Jude receives from licensing patent rights related to TPMT polymorphisms as clinical diagnostics. Patents & Royalties.

Induction of potential protective immunity against enterotoxemia in calves by single or multiple recombinant Clostridium perfringens toxoids.

Cattle enterotoxemia caused by Clostridium perfringens toxins is a noncontagious, sporadic, and fatal disease characterized by sudden death. Strategies for controlling and preventing cattle enterotoxemia are based on systematic vaccination of herds with toxoids. Because the process of producing conventional clostridial vaccines is dangerous, expensive, and time-consuming, the prospect of recombinant toxoid vaccines against diseases caused by C. perfringens toxins is promising. In this study, nontoxic recombinant toxoids derived from α-, β- and ε-toxins of C. perfringens, namely, rCPA247-370 , rCPB and rEtxHP, respectively, were expressed in Escherichia coli. High levels of specific IgG antibodies and neutralizing antibodies against the toxins were detected in sera from calves vaccinated with either a single recombinant toxoid or a mixed cocktail of all three recombinant toxoids, indicating the potential of these recombinant toxoids to provide calves with protective immunity against enterotoxemia caused by C. perfringens.

Visual evoked potentials in examining the visual analyzer in patients with multiple sclerosis

Objective: to study the neurophysiological features of the visual analyzer in patients with multiple sclerosis (MS) to optimize the early diagnosis of the disease. Patients and methods. Seventy-nine patients (57 women and 22 men, mean age 34.31±4.7 years) diagnosed as having MS were examined. The mean duration of the disease with consideration for its clinical form was 3.3±2.2 years in relapsing-remitting MS (RRMS), 9.1±4.2 years in secondary progressive MS (SPMS), and 2.7±1.9 years in primary progressive MS (PPMS). Results and discussion. The neurophysiological examination indicated that demyelination processes in MS proceeded differently in response to dissimilar lights in the structures of the visual analyzer. The most marked significant (p<0.01) deviations in the values of visual evoked potentials (VEPs) to the black-white tessellated pattern (TP) were observed in the patients with SPMS and in those with PPMS. The latency of the P100 wave increased dramatically and differed significantly (p<0.001) from those in the control group (127.09 msec for RRMS, 128.3 msec for SPMS, 124.5 msec for PPMS, and 106.1 msec in the control). Amplitude analysis could reveal a significant decrease in the force of a N75–N100 wave response to the black-white stimulus in all the clinical groups, averaging 3.3 μW (8.5 μW in the control). The latency of the P100 wave to the red-yellow TP increased considerably and differed significantly (p<0.001) from that in the control group, by comprising 147.29±1.19 msec for RRMS, 150.23±1.49 msec for SPMS, and 144.38±2.11 msec for PPMS. There were the same changes that to the greenblack TP. Examination of 25 patients with MS established higher levels of IgG antibodies against myelin basic protein. The most significant latency increase occurs in response to the color spectrum of visible light against the black-white background, which may serve as an early diagnostic criterion for MS. These changes lead to a sharp decrease in a cortical feedback. The use of the color pattern will largely contribute to the improved early diagnosis of MS.

The correlation between Toxoplasma gondii infection and Parkinson's disease: a case-control study.

Toxoplasma gondii is an obligate intracellular parasite that infects all nucleate cells of vertebrates. Human infected by vertical transmission and also using raw or undercooked meat or food and water that contaminated with mature oocysts. Parkinson's disease as neurodegenerative disease affects people above 60years. Due to high prevalence of toxoplasmosis in Iran and evidence about effects of T. gondii on neurodegenerative diseases, this study has been conducted to investigate possible correlation between Toxoplasma and Parkinson's disease in Iran. Seventy five Parkinson's patients and equal healthy volunteers were enrolled. After obtaining informed consent and sociodemographic features, 5ml blood sample were collected and then anti-Toxoplasma IgG and IgM levels were examined by ELISA method. Data was analyzed with Chi-squre and Fisher's test by usig stata 11 software. Binary logistic regression was used for multivariate analysis in assessing the correlation between toxoplasmosis and Parkinson. Eighty five percent of Parkinson's group and 90.3% of control group were positive for anti-Toxoplasma IgG antibody. In this investigation no statically differences were observed between groups and age, gender, residency and using raw or undercooked meat. There is no significant association between IgG positive titer and Parkinson's disease. However, statistically significant association was found between Parkinson and keeping cat (P=0.03) as well as the using of undercooked egg (P=0.004). Although there is high level of anti-Toxoplasma IgG antibody in Parkinson's patients which reflects chronic Toxoplasma infection; we couldn't detect any statistical association between T. gondii infection and Parkinson's disease.

Cloning, expression and characterization of protein disulfide isomerase of Schistosoma japonicum

The excretory/secretory (ES) proteins of schistosomes play important roles in modulating host immune systems and are regarded as potential vaccine candidates and drug targets. Protein disulfide isomerase (PDI) is an essential enzyme that is involved in disulfide bond formation and rearrangement. In the present study, SjPDI, a 52.8 kDa protein previously identified in a proteomics analysis as one of the ES proteins of Schistosoma japonicum, was cloned and characterized. Western blot analysis showed that recombinant SjPDI (rSjPDI) was recognized by serum from rabbits vaccinated with schistosome worm antigen. Worm protein extracts and ES protein extracts from S. japonicum could react with anti-rSjPDI mouse serum. Real-time PCR analysis indicated that SjPDI was expressed at all developmental stages tested, and a high expression level was detected in 42-day-old male worms. Immunofluorescence analysis revealed that SjPDI was mainly distributed on the tegument and parenchyma of S. japonicum worms. An enzyme-linked immunosorbent assay (ELISA) demonstrated that rSjPDI could induce a high level of rSjPDI-specific IgG antibodies. The biological activity of purified rSjPDI was confirmed by isomerization and antioxidative activity assays. The 35.32%, 26.19% reduction in the worm burden and 33.17%, 31.7% lower liver egg count were obtained in mice vaccinated with rSjPDI compared with the blank control group in two independent trials. Our preliminary results suggest that rSjPDI plays an important role in the development of the schistosome and is a potential vaccine candidate for schistosomiasis.

Evaluation of immuno-efficacy of a novel DNA vaccine encoding Toxoplasma gondii rhoptry protein 38 (TgROP38) against chronic toxoplasmosis in a murine model.

BackgroundToxoplasma gondii is an obligate intracellular parasite which can infect almost all mammalian animals, leading to toxoplasmosis. T. gondii rhoptry protein 38 (TgROP38) is an active rhoptry protein kinase which is involved in the inhibitory effect on host cell transcription by down-regulating the MAPK signaling track.MethodsTgROP38 gene was amplified and inserted into eukaryotic vector pVAX I and formed the DNA vaccine pVAX-ROP38. Mice in the experimental group were intramuscularly immunized with pVAX-ROP38 and those injected with pVAX I, PBS or nothing were treated as controls. After three injections at two week intervals, all mouse groups were challenged intraperitoneally with 1000 tachyzoites of the virulent T. gondii RH strain (Type I, ToxoDB #10) and 10 cysts of the PRU strain (Type II, ToxoDB #1), respectively.ResultsMice inoculated with pVAX-ROP38 vaccine had a higher level of IgG antibodies (P < 0.01) and T lymphoproliferative response. The high ratio of IgG2a/IgG1 and the increasing levels of IFN-γ and IL-2 (P < 0.05) indicated an activated Th1 cell-mediated immune responses. Furthermore, the CD4+ and CD8+ proportions in vaccinated mice were also increased significantly compared with that in mice of the three control groups (P < 0.01). In the model of acute infection, the average survival time of mice in the pVAX-ROP38 group (8.1 days ± 0.75) was no statistically different compared to that in the PBS, pVAX I and blank control groups which died within 7 days. However, in the model of chronic infection, the brain cyst reduction in the pVAX-ROP38 group reached 76.6%, compared to controls (P < 0.01).ConclusionsThe present study revealed that the pVAX-ROP38 vaccine could elicit strong humoral and cell immunity response against chronic T. gondii infection in mice, resulting in the reduction of the brain cyst formation effectively, which suggests that TgROP38 is a desirable vaccine candidate against chronic T. gondii infection.Electronic supplementary materialThe online version of this article (doi:10.1186/1471-2334-14-525) contains supplementary material, which is available to authorized users.

Galactosylated liposome as a dendritic cell-targeted mucosal vaccine for inducing protective anti-tumor immunity

Mucosal surfaces contain specialized dendritic cells (DCs) that are able to recognize foreign pathogens and mount protective immunity. We previously demonstrated that intranasal administration of targeted galactosylated liposomes can elicit mucosal and systemic antibody responses. In the present study, we assessed whether galactosylated liposomes could act as an effective DC-targeted mucosal vaccine that would be capable of inducing systemic anti-tumor immunity as well as antibody responses. We show that targeted galactosylated liposomes effectively facilitated antigen uptake by DCs beyond that mediated by unmodified liposomes both in vitro and in vivo. Targeted galactosylated liposomes induced higher levels of pro-inflammatory cytokines than unmodified liposomes in vitro. C57BL/6 mice thrice immunized intranasally with ovalbumin (OVA)-encapsulated galactosylated liposomes produced high levels of OVA-specific IgG antibodies in their serum. Spleen cells from mice receiving galactosylated liposomes were restimulated with OVA and showed significantly augmented levels of IFN-γ, IL-4, IL-5 and IL-6. In addition, intranasal administration of OVA-encapsulated beta-galactosylated liposomes resulted in complete protection against EG7 tumor challenge in C57BL/6 mice. Taken together, these results indicate that nasal administration of a galactosylated liposome vaccine mediates the development of an effective immunity against tumors and might be useful for further clinical anti-tumoral applications.

Covalent bond or noncovalent bond: a supramolecular strategy for the construction of chemically synthesized vaccines.

A novel noncovalent strategy to construct chemically synthesized vaccines has been designed to trigger a robust immune response and to dramatically improve the efficiency of vaccine preparation. Glycosylated MUC1 tripartite vaccines were constructed through host-guest interactions with cucurbit[8]uril. These vaccines elicited high levels of IgG antibodies that were recognized by transformed cells and induced the secretion of cytokines. The antisera also mediated complement-dependent cytotoxicity. This noncovalent strategy with good suitability, scalability, and feasibility can be applied as a universal strategy for the construction of chemically synthesized vaccines.

Lesson of the month: extrinsic allergic (bronchiolo)alveolitis and metal working fluids

One of us was asked to consider a diagnosis of occupational asthma for a man who had worked for 20 years as a metal turner in a large, modern factory...

Immunization against multidrug-resistant Acinetobacter baumannii effectively protects mice in both pneumonia and sepsis models.

Objective Acinetobacter baumannii is considered the prototypical example of a multi- or pan- drug-resistant bacterium. It has been increasingly implicated as a major cause of nosocomial and community-associated infections. This study proposed to evaluate the efficacy of immunological approaches to prevent and treat A. baumannii infections.MethodsMice were immunized with outer membrane vesicles (OMVs) prepared from a clinically isolated multidrug-resistant strain of A. baumannii. Pneumonia and sepsis models were used to evaluate the efficacy of active and passive immunization with OMVs. The probable effective mechanisms and the protective potential of clonally distinct clinical isolates were investigated in vitro using an opsonophagocytic assay.ResultsIntramuscular immunization with OMVs rapidly produced high levels of OMV-specific IgG antibodies, and subsequent intranasal challenge with A. baumannii elicited mucosal IgA and IgG responses. Both active and passive immunization protected the mice from challenges with homologue bacteria in a sepsis model. Bacterial burden in bronchoalveolar lavage fluids (BALF), lung, and spleen, inflammatory cell infiltration in BALF and lung, and inflammatory cytokine accumulation in BALF was significantly suppressed in the pneumonia model by both active and passive immunization strategies. The antisera from immunized mice presented with significant opsonophagocytic activities in a dose-dependent manner against not only homologous strains but also five of the other six clonally distinct clinical isolates.ConclusionsUtilizing immunological characteristics of outer membrane proteins to elevate protective immunity and circumvent complex multidrug-resistance mechanisms might be a viable approach to effectively control A. baumannii infections.

Vaccine strategies against Babesia bovis based on prime-boost immunizations in mice with modified vaccinia Ankara vector and recombinant proteins

In this study, a recombinant modified vaccinia virus Ankara vector expressing a chimeric multi-antigen was obtained and evaluated as a candidate vaccine in homologous and heterologous prime-boost immunizations with a recombinant protein cocktail. The chimeric multi-antigen comprises immunodominant B and T cell regions of three Babesia bovis proteins. Humoral and cellular immune responses were evaluated in mice to compare the immunogenicity induced by different immunization schemes. The best vaccination scheme was achieved with a prime of protein cocktail and a boost with the recombinant virus. This scheme induced high level of specific IgG antibodies and secreted IFN and a high degree of activation of IFNγ+ CD4+ and CD8+ specific T cells. This is the first report in which a novel vaccine candidate was constructed based on a rationally designed multi-antigen and evaluated in a prime-boost regime, optimizing the immune response necessary for protection against bovine babesiosis.

THU0408 Anti-Lactoferrin Autoantibodies Contribute to the Pathogenesis of Igg4-Related Disease by Inducing Neutrophil Extracellular TRAP Formation

BackgroundIgG4-related disease (IgG4-RD) is a newly recognized fibroinflammatory condition characterized by infiltration of IgG4-positive plasma cells into the pancreas, biliary tracts, or salivary glands. In addition to helper type 2...

Hypoallergenic derivatives of Fel d 1 obtained by rational reassembly for allergy vaccination and tolerance induction

The major cat allergen Fel d 1 represents one of the most important respiratory allergens. Aim of this study was to engineer recombinant Fel d 1 derivatives with reduced IgE reactivity and preserved T cell epitopes for vaccination and tolerance induction. Seven recombinant mosaic proteins were generated by reassembly of non-IgE-reactive peptides of Fel d 1 which contained the sequence elements for induction of allergen-specific blocking IgG antibodies and T cell epitopes. Mosaic proteins were expressed in Escherichia coli using codon-optimized synthetic genes and compared with Fel d 1 regarding structural fold by circular dichroism, IgE-binding capacity, activation of allergic patients' basophils and ability to induce allergen-specific blocking IgG antibodies upon immunization. Although each of the mosaic proteins had lost the alpha-helical fold typical for Fel d 1, a strong reduction in IgE reactivity as well as allergenic activity in basophil activation assays was only obtained for three constructs, two reassembled fragments (Fel d 1 MB, Fel d 1 MC) and a fusion of the latter two (Fel d 1 MF) in which the cysteines of Fel d 1 MC were replaced by serines. Immunization of rabbits with Fel d 1 MB, MC and MF induced high levels of IgG antibodies that inhibited IgE reactivity of cat-allergic patients to Fel d 1 in a comparable manner as IgG induced with the wild-type allergen. We report the development of hypoallergenic reassembled Fel d 1 proteins suitable for vaccination and tolerance induction in cat-allergic patients.

Immunological characterization of a chimeric form of Schistosoma mansoni aquaporin in the murine model.

Aquaporin (SmAQP) is the most abundant transmembrane protein in the tegument of Schistosoma mansoni. This protein is expressed in all developmental stages and seems to be essential in parasite survival since it plays a crucial role in osmoregulation, nutrient transport and drug uptake. In this study, we utilized the murine model to evaluate whether this protein was able to induce protection against challenge infection with S. mansoni cercariae. A chimeric (c) SmAQP was formulated with Freund's adjuvant for vaccination trial and evaluation of the host's immune response was performed. Our results demonstrated that immunization with cSmAQP induced the production of high levels of specific anti-cSmAQP IgG antibodies and a Th1/Th17 type of immune response characterized by IFN-γ, TNF-α and IL-17 cytokines. However, vaccination of mice with cSmAQP failed to reduce S. mansoni worm burden and liver pathology. Finally, we were unable to detect humoral immune response anti-cSmAQP in the sera of S. mansoni-infected human patients. Our results lead us to believe that SmAQP, as formulated in this study, may not be a good target in the search for an anti-schistosomiasis vaccine.

Serological Assessment for Celiac Disease in IgA Deficient Adults

PurposeSelective immunoglobulin A deficiency is the most common primary immunodeficiency disorder that is strongly overrepresented among patients with celiac disease (CD). IgG antibodies against tissue transglutaminase (tTG) and deamidated gliadin peptides (DGP) serve as serological markers for CD in IgA deficient individuals, although the diagnostic value remains uncertain. The aim of this study was to investigate the prevalence of these markers in a large cohort of IgA deficient adults with confirmed or suspected CD and relate the findings to gluten free diet.MethodsSera from 488,156 individuals were screened for CD in seven Swedish clinical immunology laboratories between 1998 and 2012. In total, 356 out of 1,414 identified IgA deficient adults agreed to participate in this study and were resampled. Forty-seven IgA deficient blood donors served as controls. Analyses of IgG antibodies against tTG and DGP as well as HLA typing were performed and a questionnaire was used to investigate adherence to gluten free diet. Available biopsy results were collected.ResultsOut of the 356 IgA deficient resampled adults, 67 (18.8%) were positive for IgG anti-tTG and 79 (22.2%) for IgG anti-DGP, 54 had biopsy confirmed CD. Among the 47 IgA deficient blood donors, 4 (9%) were positive for IgG anti-tTG and 8 (17%) for anti-DGP. Four were diagnosed with biopsy verified CD, however, 2 of the patients were negative for all markers. Sixty-eight of 69 individuals with positive IgG anti-tTG were HLA-DQ2/DQ8 positive whereas 7 (18.9%) of the 37 individuals positive for IgG anti-DGP alone were not.ConclusionsIgG anti-tTG seems to be a more reliable marker for CD in IgA deficient adults whereas the diagnostic specificity of anti-DGP appears to be lower. High levels of IgG antibodies against tTG and DGP were frequently found in IgA deficient adults despite adhering to gluten free diet.

Phase Variation Mediates Reductions in Expression of Surface Proteins during Persistent Meningococcal Carriage

Asymptomatic and persistent colonization of the upper respiratory tract by Neisseria meningitidis occurs despite elicitation of adaptive immune responses against surface antigens. A putative mechanism for facilitating host persistence of this bacterial commensal and pathogen is alterations in expression of surface antigens by simple sequence repeat (SSR)-mediated phase variation. We investigated how often phase variation occurs during persistent carriage by analyzing the SSRs of eight loci in multiple isolates from 21 carriers representative of 1 to 6 months carriage. Alterations in repeat number were detected by a GeneScan analysis and occurred at 0.06 mutations/gene/month of carriage. The expression states were determined by Western blotting and two genes, fetA and nadA, exhibited trends toward low expression states. A critical finding from our unique examination of combinatorial expression states, "phasotypes," was for significant reductions in expression of multiple phase-variable surface proteins during persistent carriage of some strains. The immune responses in these carriers were examined by measuring variant-specific PorA IgG antibodies, capsular group Y IgG antibodies and serum bactericidal activity in concomitant serum samples. Persistent carriage was associated with high levels of specific IgG antibodies and serum bactericidal activity while recent strain acquisition correlated with a significant induction of antibodies. We conclude that phase-variable genes are driven into lower expression states during long-term persistent meningococcal carriage, in part due to continuous exposure to antibody-mediated selection, suggesting localized hypermutation has evolved to facilitate host persistence.

Thrombotic thrombocytopenic purpura due to anti-ADAMTS13 antibodies in multiple myeloma

Thrombotic thrombocytopenic purpura (TTP) is a particularly serious form of thrombotic microangiopathy (TMA) due to the risk of multiple organ dysfunction. Several etiological factors such as infection, auto-immune disease, certain medications and cancers have been associated with TTP. A 74-year-old hypertensive woman with a history of thromboembolic disease was hospitalized for acute kidney injury (AKI) associated with pneumonia. Initial investigations were suggestive of Pneumocystis jirovecii infection and myeloma cast nephropathy. Several days later, the patient presented features of TTP. Von Willebrand factor-cleaving protease activity was less than 5% with a high level of IgG antibody directed against ADAMTS13. Treatment consisted of monthly 4-day cycles of dexamethasone and melphalan in combination with plasmapheresis and resulted in a favorable outcome. Three years after ceasing treatment, the patient presented no signs of hemolysis, but required chronic hemodialysis. The association of TMA, especially TTP, and multiple myeloma is exceptional. The authors report such a case that induced irreversible renal damage, but with stable clinical and laboratory parameters with a follow-up of 4 years.

Invasion of Oral and Aortic Tissues by Oral Spirochete Treponema denticola in ApoE −/− Mice Causally Links Periodontal Disease and Atherosclerosis

Treponema denticola is a predominantly subgingival oral spirochete closely associated with periodontal disease and has been detected in atherosclerosis. This study was designed to evaluate causative links between periodontal disease induced by chronic oral T. denticola infection and atherosclerosis in hyperlipidemic ApoE(-/-) mice. ApoE(-/-) mice (n = 24) were orally infected with T. denticola ATCC 35404 and were euthanized after 12 and 24 weeks. T. denticola genomic DNA was detected in oral plaque samples, indicating colonization of the oral cavity. Infection elicited significantly (P = 0.0172) higher IgG antibody levels and enhanced intrabony defects than sham infection. T. denticola-infected mice had higher levels of horizontal alveolar bone resorption than sham-infected mice and an associated significant increase in aortic plaque area (P ≤ 0.05). Increased atherosclerotic plaque correlated with reduced serum nitric oxide (NO) levels and increased serum-oxidized low-density lipoprotein (LDL) levels compared to those of sham-infected mice. T. denticola infection altered the expression of genes known to be involved in atherosclerotic development, including the leukocyte/endothelial cell adhesion gene (Thbs4), the connective tissue growth factor gene (Ctgf), and the selectin-E gene (Sele). Fluorescent in situ hybridization (FISH) revealed T. denticola clusters in both gingival and aortic tissue of infected mice. This is the first study examining the potential causative role of chronic T. denticola periodontal infection and vascular atherosclerosis in vivo in hyperlipidemic ApoE(-/-) mice. T. denticola is closely associated with periodontal disease and the rapid progression of atheroma in ApoE(-/-) mice. These studies confirm a causal link for active oral T. denticola infection with both atheroma and periodontal disease.