Animal-to-Human Dose Translation of ANTHRASIL for Treatment of Inhalational Anthrax in Healthy Adults, Obese Adults, and Pediatric Subjects

Anthrax Immune Globulin Intravenous (AIGIV [ANTHRASIL]), was developed for the treatment of toxemia associated with inhalational anthrax. It is a plasma product collected from individuals vaccinated with anthrax vaccine and contains antitoxin IgG antibodies against Bacillus anthracis protective antigen. A pharmacokinetic (PK) and exposure-response model was constructed to assess the PKs of AIGIV in anthrax-free and anthrax-exposed rabbits, non-human primates and anthrax-free humans, as well as the relationship between AIGIV exposure and survival from anthrax, based on available preclinical/clinical studies. The potential effect of anthrax on the PKs of AIGIV was evaluated and estimates of survival odds following administration of AIGIV protective doses with and without antibiotic co-treatment were established. As the developed PK model can simulate exposure of AIGIV in any species for any dosing scenario, the relationship between the predicted area under the concentration curve of AIGIV in humans and the probability of survival observed in preclinical studies was explored. Based on the simulation results, the intravenous administration of 420 U (units of potency as measured by validated Toxin Neutralization Assay) of AIGIV is expected to result in a > 80% probability of survival in more than 90% of the human population. Additional simulations suggest that exposure levels were similar in healthy and obese humans, and exposure in pediatrics is expected to be up to approximately seven-fold higher than in healthy adults, allowing for doses in pediatric populations that ranged from one to seven vials. Overall, the optimal human dose was justified based on the PK/pharmacodynamic (PD) properties of AIGIV in animals and model-based translation of PK/PD to predict human exposure and efficacy.

Molecular characterization of Helicobacter pylori clinical isolates from Eastern Saudi Arabia

OBJECTIVES

To describe the frequency of cytotoxin-associated gene A (CagA) and vacuolating cytotoxin A (VacA) virulence genes and clarithromycin resistance-associated mutations among Helicobacter pylori (H. pylori) clinical isolates from Eastern Saudi Arabia.

METHODS

A cross-sectional study was carried out between July 2020 and June 2021 in a tertiary hospital in AL-Khobar, Saudi Arabia. A total of 34 H. pylori isolates were obtained from gastric biopsies of patients with dyspepsia. The existence of the virulence genes was studied by polymerase chain reaction and the gene fragment of the 23s ribosomal subunit (23s rRNA) gene was sequenced.

RESULTS

All isolates harbored the CagA gene. Approximately 97.1% (33/34) isolates were positive using the VacA M primer and 91.2% (31/34) isolates were positive using the VacA S primer. The most frequent allelic combination was S2/M2/cag (60%), followed by S1/M2/cag (26.7%), S1/M1/cag (10%), and S2/M1/cag (3.3%). Approximately 6.5% isolates harbored the A2142G mutation and 29% isolates harbored the A2143G mutation. One isolate contained the mutation T2182C. The phylogenetic analysis showed that 58% isolates clustered with the regional and global isolates while the remaining 42% isolates seemed to be specifically circulating in Saudi Arabia. Most of the patients (73.5%) had already underwent a previous H. pylori eradication therapy.

CONCLUSION

We showed that there is a regional variation in the frequency of the virulence genes among H. pylori isolates. Additionally, we showed the frequency of 23s rRNA mutations related to clarithromycin resistance in Saudi Arabia.

Effects of trans-resveratrol on type 1 diabetes-induced up-regulation of apoptosis and mitogen-activated protein kinase signaling in retinal pigment epithelium of Dark Agouti rats

Microvascular changes and retinal degeneration precede diabetic retinopathy. Oxidative stress alters several intracellular signaling pathways, which form the basis of diabetic retinopathy. Many antioxidants have been investigated as possible preventive and therapeutic remedies for diabetic retinopathy. The current study investigated the modulatory effects of trans-resveratrol on streptozotocin-induced type 1 diabetes mediated changes in the transcription and levels of apoptosis-related proteins and mitogen-activated protein kinases (MAPKs) in the retinal pigment epithelium (RPE) of adult male dark Agouti rats. In control rats, 5 mg/kg/d trans-resveratrol administration for 30 days increased gene expressions of tumor suppressor protein 53, Bcl2-associated X protein, B-cell lymphoma-2 (Bcl2), Caspase-3 (CASP3), CASP8 and CASP9, p38αMAPK, c-Jun N-terminal kinase-1 (JNK1), and extracellular signal-regulated kinase-1 (ERK1). On the other hand, diabetes decreased gene expressions of CASP3, CASP8, p38αMAPK, JNK, and ERK1. Trans-resveratrol reversed the inhibited gene expressions of CASP8, p38αMAPK, JNK, and ERK1 to normal control levels in diabetic rats. Trans-resveratrol normalized diabetes-induced upregulation of CASP3 and -9, cytochrome-c, Bcl-2, and ERK1 proteins. In conclusion, Trans-resveratrol-induced alterations in gene expressions do not seem to affect RPE functions as they do not reflect as altered protein functions. Trans-resveratrol imparts its protective effects by normalizing apoptosis-related proteins and ERK1 but does not affect JNK proteins. Trans-resveratrol causes cytostasis in RPE of normal rats by upregulating Bcl2 protein and apoptotic proteins.

Subunit Vaccines Using TLR Triagonist Combination Adjuvants Provide Protection Against Coxiella burnetii While Minimizing Reactogenic Responses

Q fever is caused by the obligate intracellular bacterium, Coxiella burnetii, a designated potential agent of bioterrorism because of its route of transmission, resistance to disinfectants, and low infectious dose. The only vaccine licensed for human use is Q-VAX® (Seqirus, licensed in Australia), a formalin-inactivated whole-cell vaccine, which produces severe local and systemic reactogenic responses in previously sensitized individuals. Accordingly, the U.S. Food and Drug Administration and other regulatory bodies around the world, have been reluctant to approve Q-VAX for widespread use. To obviate these adverse reactions, we prepared recombinant protein subunit vaccine candidates containing purified CBU1910, CBU0307, CBU0545, CBU0612, CBU0891, and CBU1398 proteins and TLR triagonist adjuvants. TLR triagonist adjuvants combine different TLR agonists to enhance immune responses to vaccine antigens. We tested both the protective efficacy and reactogenicity of our vaccine candidates in Hartley guinea pigs using intratracheal infection with live C. burnetii. While all of our candidates showed varying degrees of protection during challenge, local reactogenic responses were significantly reduced for one of our vaccine candidates when compared with a formalin-inactivated whole-cell vaccine. Our findings show that subunit vaccines combined with novel TLR triagonist adjuvants can generate protective immunity to C. burnetii infection while reducing reactogenic responses.

Prophylactic efficacy against Mycobacterium tuberculosis using ID93 and lipid-based adjuvant formulations in the mouse model

An estimated 10 million people developed tuberculosis (TB) disease in 2019 which underscores the need for a vaccine that prevents disease and reduces transmission. The aim of our current studies is to characterize and test a prophylactic tuberculosis vaccine comprised of ID93, a polyprotein fusion antigen, and a liposomal formulation [including a synthetic TLR4 agonist (glucopyranosyl lipid adjuvant, GLA) and QS-21] in a preclinical mouse model of TB disease. Comparisons of the ID93+GLA-LSQ vaccines are also made to the highly characterized ID93+GLA-SE oil-in-water emulsion adjuvant, which are also included these studies. The recent success of vaccine candidate M72 combined with adjuvant AS01E (GlaxoSmithKline Biologicals) in reducing progression to active disease is promising and has renewed excitement for experimental vaccines currently in the TB vaccine pipeline. The AS01E adjuvant contains monophosphoryl lipid A (MPL) and QS-21 (a saponin) in a liposomal formulation. While AS01E has demonstrated potent adjuvant activity as a component of both approved and experimental vaccines, developing alternatives to this adjuvant system will become important to fill the high demand envisioned for future vaccine needs. Furthermore, replacement sources of potent adjuvants will help to supply the demand of a TB vaccine [almost one-quarter of the world's population are estimated to have latent Mycobacterium tuberculosis (Mtb) according to the WHO 2019 global TB report], addressing (a) cost of goods, (b) supply of goods, and (c) improved efficacy of subunit vaccines against Mtb. We show that both ID93+GLA-SE (containing an emulsion adjuvant) and ID93+GLA-LSQ (containing a liposomal adjuvant) induce ID93-specific TH1 cellular immunity including CD4+CD44+ T cells expressing IFNγ, TNF, and IL-2 (using flow cytometry and intracellular cytokine staining) and vaccine-specific IgG2 antibody responses (using an ELISA). In addition, both ID93+GLA-SE and ID93+GLA-LSQ effectively decrease the bacterial load within the lungs of mice infected with Mtb. Formulations based on this liposomal adjuvant formulation may provide an alternative to AS01 adjuvant systems.

Inhibitory Effects of a Reengineered Anthrax Toxin on Canine Oral Mucosal Melanomas

Canine oral mucosal melanomas (OMM) are the most common oral malignancy in dogs and few treatments are available. Thus, new treatment modalities are needed for this disease. Bacillus anthracis (anthrax) toxin has been reengineered to target tumor cells that express urokinase plasminogen activator (uPA) and metalloproteinases (MMP-2), and has shown antineoplastic effects both, in vitro and in vivo. This study aimed to evaluate the effects of a reengineered anthrax toxin on canine OMM. Five dogs bearing OMM without lung metastasis were included in the clinical study. Tumor tissue was analyzed by immunohistochemistry for expression of uPA, uPA receptor, MMP-2, MT1-MMP and TIMP-2. Animals received either three or six intratumoral injections of the reengineered anthrax toxin prior to surgical tumor excision. OMM samples from the five dogs were positive for all antibodies. After intratumoral treatment, all dogs showed stable disease according to the canine Response Evaluation Criteria in Solid Tumors (cRECIST), and tumors had decreased bleeding. Histopathology has shown necrosis of tumor cells and blood vessel walls after treatment. No significant systemic side effects were noted. In conclusion, the reengineered anthrax toxin exerted inhibitory effects when administered intratumorally, and systemic administration of this toxin is a promising therapy for canine OMM.

A Clinical Trial on Oral H. pylori Infection of Preschool Children

GOALS

Over the past twenty years, the existence of oral Helicobacter pylori (H. pylori) infection has been controversial and is still disputed. It proposes that living H. pylori do not exist in the oral cavity. However, the progressive loss of efficacy of standard eradication therapies has made the treatment of H. pylori more challenging than ever due to oral H. pylori infection. We conducted a study to explore the existence of oral H. pylori infection in preschool children.

PROCEDURES

A total of 178 children were recruited and evaluated using the saliva H. pylori antigen test (HPS) and the urea breath test (UBT C¹³) to diagnose oral and stomach H. pylori infections, respectively. The treatments of oral H. pylori infection included toothpaste only, and toothpaste combined with mouth washing morning and night daily for two months. Group A: Children live with parents who have a stomach disease history. Group B: Children live with parents who have no stomach disease history. Group C: Children with toothpaste treatment. Group D: Children with combined toothpaste and mouth rinse treatments. Group E: Control group with no treatments.

RESULTS

The positive rate of HPS and C¹³ were 76.4% and 15.73% in the 95% confidence interval (95% CI) range, respectively, among the 178 children. The positive rate of HPS was significantly higher (p<0.001) with the parents who suffered from stomach H. pylori infections which had been diagnosed by C¹³. After two-month treatments, Group D and Group E provided 26.87% and 26.44% (95% CI) range efficient rates of the oral H. pylori infection, respectively. The difference between the C, D, and E groups was significant (p<0.001).

CONCLUSION

Oral H. pylori exists in the oral cavity of preschool children. The positive rate of HPS was higher with parents suffering from stomach disease, and treatment was effective in reducing oral infection.

Microtubule affinity-regulating kinases are potential druggable targets for Alzheimer's disease

Alzheimer's disease (AD) is a progressive neurodegenerative disorder that affects normal functions of the brain. Currently, AD is one of the leading causes of death in developed countries and the only one of the top ten diseases without a means to prevent, cure, or significantly slow down its progression. Therefore, newer therapeutic concepts are urgently needed to improve survival and the quality of life of AD patients. Microtubule affinity-regulating kinases (MARKs) regulate tau-microtubule binding and play a crucial role in neurons. However, their role in hyperphosphorylation of tau makes them potential druggable target for AD therapy. Despite the relevance of MARKs in AD pathogenesis, only a few small molecules are known to have anti-MARK activity and not much has been done to progress these compounds into therapeutic candidates. But given the diverse role of MARKs, the specificity of novel inhibitors is imperative for their successful translation from bench to bedside. In this regard, a recent co-crystal structure of MARK4 in association with a pyrazolopyrimidine-based inhibitor offers a potential scaffold for the development of more specific MARK inhibitors. In this manuscript, we review the biological role of MARKs in health and disease, and draw attention to the largely unexplored area of MARK inhibitors for AD.

A systematic review and meta-analysis of preclinical trials testing anti-toxin therapies for B. anthracis infection: A need for more robust study designs and results

BACKGROUND

B. anthracis anti-toxin agents are approved and included in the Strategic National Stockpile based primarily on animal infection trials. However, in the only anthrax outbreak an approved anti-toxin agent was administered in, survival did not differ comparing recipients and non-recipients, although recipients appeared sicker.

OBJECTIVE

Employ a systematic review and meta-analysis to investigate preclinical studies supporting anthrax anti-toxin agents.

DATA SOURCE

PubMed, EMBASE, and Scopus.

STUDY ELIGIBILITY

Compared survival with an anti-toxin agent versus control in B. anthracis challenged, antibiotic treated animals.

STUDY METHODS

Examine model and study design and the effect of anti-toxin agents on relative risk of death(95%CI) (RR).

RESULTS

From 9 studies, 29 experiments were analyzed which included 4 species (748 animals) and 5 agents; LFI, AIG, AVP-21D9, Raxibacumab, and ETI-204. Only five experiments were blinded and no experiment included the cardiopulmonary support sick B. anthracis patients receive. Only one agent in a single un-blinded experiment reduced RR significantly [0.45(0.22,0.940]. However, in six studies testing an agent in more than one experiment in the same species, agents had consistent survival effects across experiments [I2 = 0, p≥0.55 in five and I2 = 42%, p = 0.16 in one]. Within each species, agents had effects on the side of benefit; in one study testing AVP-21D9 in mice [0.11(0.01,1.82)] or guinea pigs [0.70(0.48,1.03)]; across eight rabbit studies testing LFI, Raxibacumab, AIG or ETI-204 [0.62(0.45,0.87); I2 = 17.4%, p = 0.29]; and across three monkey studies testing Raxibacumab, AIG or ETI-204 [0.66(0.34,1.27); I2 = 25.3%, p = 0.26]. Across all agents and species, agents decreased RR [0.64(0.52,0.79); I2 = 5.3%, p = 0.39].

LIMITATIONS

Incidence of selective reporting not identifiable.

CONCLUSIONS

Although overall significant, individually anti-toxin agents had weak beneficial effects. Lack of study blinding and relevant clinical therapies further weakened studies. Although difficult, preclinical studies with more robust designs and results are warranted to justify the resources necessary to maintain anti-toxin agents in national stockpiles.

Identification of novel antigen candidates for a tuberculosis vaccine in the adult zebrafish (Danio rerio)

Tuberculosis (TB) remains a major global health challenge and the development of a better vaccine takes center stage in fighting the disease. For this purpose, animal models that are capable of replicating the course of the disease and are suitable for the early-stage screening of vaccine candidates are needed. A Mycobacterium marinum infection in adult zebrafish resembles human TB. Here, we present a pre-clinical screen for a DNA-based tuberculosis vaccine in the adult zebrafish using an M. marinum infection model. We tested 15 antigens representing different types of mycobacterial proteins, including the Resuscitation Promoting factors (Rpf), PE/PPE protein family members, other membrane proteins and metabolic enzymes. The antigens were expressed as GFP fusion proteins, facilitating the validation of their expression in vivo. The efficiency of the antigens was tested against a low-dose intraperitoneal M. marinum infection (≈ 40 colony forming units), which mimics a primary M. tuberculosis infection. While none of the antigens was able to completely prevent a mycobacterial infection, four of them, namely RpfE, PE5_1, PE31 and cdh, led to significantly reduced bacterial burdens at four weeks post infection. Immunization with RpfE also improved the survival of the fish against a high-dose intraperitoneal injection with M. marinum (≈ 10.000 colony forming units), resembling the disseminated form of the disease. This study shows that the M. marinum infection model in adult zebrafish is suitable for the pre-clinical screening of tuberculosis vaccines and presents RpfE as a potential antigen candidate for further studies.

A Multistage Subunit Vaccine Effectively Protects Mice Against Primary Progressive Tuberculosis, Latency and Reactivation

Adult tuberculosis (TB) is the main cause of TB epidemic and death. The infection results mainly by endogenous reactivation of latent TB infection and secondarily transmitted by exogenous infection. There is no vaccine for adult TB. To this end, we first chose antigens from a potential antigenic reservoir. The antigens strongly recognized T cells from latent and active TB infections that responded to antigens expressed by Mycobacterium tuberculosis cultured under different metabolic states. Fusions of single-stage polyprotein CTT3H, two-stage polyprotein A1D4, and multistage CMFO were constructed. C57BL/6 mice vaccinated with DMT adjuvant ed CMFO (CMFO-DMT) were protected more significantly than by CTT3H-DMT, and efficacy was similar to that of the only licensed vaccine, Bacillus Calmette–Guérin (BCG) and A1D4-DMT in the M. tuberculosis primary infection model. In the setting of BCG priming and latent TB infection, M. tuberculosis in the lung and spleen was eliminated more effectively in mice boosted with CMFO-DMT rather than with BCG, A1D4-DMT, or CTT3H-DMT. In particular, sterile immunity was only conferred by CMFO-DMT, which was associated with expedited homing of interferon-gamma⁺ CD4⁺ T_EM and interleukin-2⁺ T_CM cells from the spleen to the infected lung. CMFO-DMT represents a promising candidate to prevent the occurrence of adult TB through both prophylactic and therapeutic methods, and warrants assessment in preclinical and clinical trials.

•

CMFO-DMT provides the comparable protection against primary infection with M. tuberculosis as BCG vaccine does.

•

CMFO-DMT boosts an effective protection of BCG primed mice to eliminate latent infection and thwart reactivation.

•

CMFO-DMT is a promising vaccine candidate for the prevention of adult TB disease.

Adult pulmonary TB is the main clinical form of the disease and the main component of TB epidemics. There is no effective vaccine to protect adults from primary and secondary TB. Vaccine candidates were constructed using combinations of one-, two- or multi-stage antigens of M. tuberculosis representing different stages of the infection. The antigen combinations directed at different stages of TB may help control adult TB.

Rapid response to a college outbreak of meningococcal serogroup B disease: Nation's first widespread use of bivalent rLP2086 vaccine

OBJECTIVE

To outline the reasoning behind use of bivalent rLP2086 in a Rhode Island college meningococcal B disease outbreak, highlighting the timeline from outbreak declaration to vaccination clinic, emphasizing that these two time points are <3 days apart.

PARTICIPANTS

Staff, faculty, and students at College X eligible for vaccination.

METHODS

An outbreak response was initiated, advantages/disadvantages of available MenB vaccines were discussed, and a vaccination clinic was coordinated.

RESULTS

Bivalent rLP2086 was chosen as the vaccination intervention. We achieved a 94% coverage rate for the first dose. To date, this intervention has prevented further cases of Neisseria meningitidis serogroup B disease at College X.

CONCLUSIONS

The close, efficient collaboration of public health stakeholders and College X led 94% of the eligible population to be safely vaccinated with at least one dose of bivalent rLP2086. This outbreak marked the first time bivalent rLP2086 was effectively used as an intervention response.

[THE CORRECTION OF THE LOCAL IMMUNE RESPONSE AT THE PATIENTS WITH HELICOBACTER PYLORI INFECTION]

INTRODUCTION

Helicobacter pylori infection is due to the high prevalence in population attracts the clinical interest of researchers in the whole World. It is well known that this microorganism not only resides in the mucosa of the gastrointestinal tract, but is also defined in the periodontal pocket of the oral cavity. THE AIM OF INVESTIGATION: to evaluate Helicobacter pylori diagnostics in the mouth and prove a method of relief of the inflammatory process by applying immunomodulator Imudon. RESULTS. On the basis of obtained results it was found that the inclusion of topical immunomodulator Imudon in the complex therapy of Helicobacter pylori-associated diseases leads to reduction of inflammatory potential through the decrease of the TNFα, IL-6 activity in saliva and to increase the protective properties of saliva as a result of increased levels of mucin, significantly reduces the frequency of relapses in the one year after therapy.

CONCLUSION

It is practically important to determine the effectiveness of eradication therapy by the study of the contents of the tooth-gingival pocket for the detection of genetic material of Helicobacter pylori, as well as to include in the complex therapy of Helicobacter pylori-associated diseases of the immune modulator Imudon.

[Immunoprophylaxis of infections of the upper respiratory tract in the frequently ill children]

The review of the clinical studies designed to evaluate the prophylactic effectiveness of ribosomal immunization is presented. It is shown that the application of the ribosomal vaccine ribomunyl causes a significant reduction in the occurrence of acute respiratory infections in the frequently ill children, lowers the frequency of exacerbation of chronic diseases of the upper respiratory tract, and allows to decrease the use of antibiotics. The authors emphasize the high therapeutic effectiveness and safety of preventive measures against respiratory infections in the frequently ill children with the use of the anti-influenza vaccine in combination with ribosomal immunization.

Effects of mycobacteria major secretion protein, Ag85B, on allergic inflammation in the lung

Many epidemiological studies have suggested that the recent increase in prevalence and severity of allergic diseases such as asthma is inversely correlated with Mycobacterium bovis bacillus Calmette Guerin (BCG) vaccination. However, the underlying mechanisms by which mycobacterial components suppress allergic diseases are not yet fully understood. Here we showed the inhibitory mechanisms for development of allergic airway inflammation by using highly purified recombinant Ag85B (rAg85B), which is one of the major protein antigens secreted from M. tuberculosis. Ag85B is thought to be a single immunogenic protein that can elicit a strong Th1-type immune response in hosts infected with mycobacteria, including individuals vaccinated with BCG. Administration of rAg85B showed a strong inhibitory effect on the development of allergic airway inflammation with induction of Th1-response and IL-17and IL-22 production. Both cytokines induced by rAg85B were involved in the induction of Th17-related cytokine-production innate immune cells in the lung. Administration of neutralizing antibodies to IL-17 or IL-22 in rAg85B-treated mice revealed that IL-17 induced the infiltration of neutrophils in BAL fluid and that allergen-induced bronchial eosinophilia was inhibited by IL-22. Furthermore, enhancement of the expression of genes associated with tissue homeostasis and wound healing was observed in bronchial tissues after rAg85B administration in a Th17-related cytokine dependent manner. The results of this study provide evidence for the potential usefulness of rAg85B as a novel approach for anti-allergic effect and tissue repair other than the role as a conventional TB vaccine.

CanNeisseria lactamicaantigens provide an effective vaccine to prevent meningococcal disease?

Neisseria lactamica is a commensal organism that is closely related to Neisseria meningitidis, the causative agent of meningococcal disease. N. lactamica has many antigens in common with N. meningitidis, but it lacks a polysaccharide capsule and the serosubtyping antigen PorA. Carriage studies have demonstrated that N. lactamica is carried in the nasopharynx of young children at a time when meningococcal carriage is rare. However, natural immunity to meningococcal disease develops during this period and carriage of commensal Neisseria is implicated in the development of this immunity. Recent studies have characterized the antigens which may be responsible for inducing a crossreactive antibody response and have demonstrated that N. lactamica-based vaccines can protect in experimental models of meningococcal disease. The potential for these vaccines to be effective in preventing meningococcal disease is discussed.

[Diagnosis and treatment of allergic rhinitis aggravated by respiratory tract infection]

The objective of the present paper was to propose an optimal scope of diagnostic studies for the patients complaining of rhinitis symptoms for the early detection of allergic rhinitis, including a differential diagnosis with associated respiratory tract infections. A comprehensive treatment is offered including the use of vasoconstrictors and antihistamines, eliminationand immunocorrectivetherapy with Ribomunyl.

Prevention of recurrent urinary tract infections in women

Around 40-50% of women experience at least one urinary tract infection (UTI) during their lifetime and 20-30% of these have a recurrence within 3-4 months of the initial infection.¹ Recurrent UTI (usually defined as three episodes in the last 12 months or two episodes in the last 6 months) can have a considerable impact on a woman's quality of life. Each episode of acute UTI in young women is typically associated with about 6 days of symptoms, 2.4 days of restricted activities and 0.4 days of bed rest.¹ Antibacterial prophylaxis is effective in preventing recurrent episodes, but at the expense of unwanted effects and a risk of promoting bacterial resistance. Here we assess the efficacy of different antibacterial regimens and non-antibacterial alternatives (cranberry, probiotics, oestrogens, immunostimulation, hyaluronic acid and chondroitin, acupuncture and herbs) in the prevention of recurrent uncomplicated UTIs in women.

[Local immunomodulating agents in complex treatment of oral lichen planus]

The paper presents the results of local immunity status assessment in patients with erosive-ulcerous form of oral lichen planus by etiopatogenetic treatment including imudone and derinate. The positive dynamics of immunological parameters under imudone and derinate is demonstrated.

[Effect of Immunovac-VP-4 and Kagocel immunotherapy on cytokine levels in patients with erythema nodosum]

Fixed erythema--a kind of clinical and histopathologic reaction, fixed drug eruption. The purpose of the study--the study of characteristics of the cytokine profile in patients with erythema and the dynamics of the basal levels of proinflammatory and antiinflammatory cytokines during immunotherapy. All 41 patients with fixed erythema at baseline and after treatment was carried out determination of levels of pro-, anti-inflammatory and regulatory cytokines in the serum by ELISA using test systems "Biosource" (Austria). In patients with fixed erythema Immunovac treatment increased serum IFN-gamma (p < 0.05), IL-1beta (p > 0.05), IL-6. While Kagocel led to an increase in IFN-gamma (p < 0.05), IL-1beta, IL-6 and reduction of TGF-beta (p < 0.05). At the same time in patients with fixed erythema basic therapy contributed to the significant increase in TGF-â and decrease in IL-10. Immunovac-VP-4 had the highest activity for the induction of IFN-gamma. Inclusion in the range of therapeutic and prophylactic measures in patients with fixed erythema immunomodulators promotes activation links innate and adaptive immunity triggers mechanisms, thus increasing the antiviral response in patients with erythema.

Efficacy and safety of ribosome-component immune modulator for preventing recurrent respiratory infections in socialized children

Attending day care is associated with recurrent respiratory infections (RRIs) and asthma. Ribosomal immunotherapy may confer protection against RRIs in children. This study was designed to assess the efficacy of a ribosome-component immune modulator (RCIM) as preventive treatment of respiratory infections in socialized children aged ≤5 years, with or without a history of frequent RRI. In a multicenter, Italian, randomized, double-blind, placebo-controlled, parallel-group study, 164 socialized day care center children (mean age, 3.8 ± 1.1 years) were treated with RCIM or placebo for 6 months and followed-up for additional 6 months. Outcomes are presented for the intent-to-treat population. In socialized children with five or less RRIs (n = 95; 49 RCIM and 46 placebo, group A) the duration of the infectious episodes was significantly shorter with RCIM than with placebo (6 months, 3.7 ± 2.1 versus 4.5 ± 1.9 days, p = 0.040; 12 months, 3.6 ± 2.0 versus 4.7 ± 2.5 days, p = 0.015). The proportion of patients reporting no respiratory infectious episodes with RCIM at 6 and 12 months was also significantly larger in group A (20.4% versus 4.4% placebo; p = 0.028). No such differences were found in children with more than five RRIs in the preceding year (n = 63; 32 RCIM and 31 placebo, group B). In all children, general well-being improved significantly more under RCIM than under placebo (11.6 ± 1.8% versus 10.2 ± 1.8%; p = 0.002). No statistically significant between-treatment differences were observed for other end points. Both treatments were similarly well tolerated. Six-month treatment with RCIM effectively prevented the 12-month risk of RRIs in children <5 years old and with five or less RRIs in the preceding year.

[Immune reactions of palatine tonsils in the patients with chronic tonsillitis and the possibilities for their immunological rehabilitation with the use of imudon]

The objective of the present study was to develop a rationale for the application of imudon (a bacterial lysate preparation)in the treatment of the patients presenting with chronic tonsillitis based on the elucidation of characteristics of local immunity in the oropharynx (determined from the results of cytograms, immunoenzyme assays for the quantitation of IgG, sIgA, IgA, and IgM antibodies, and calculation of the relative secretion coefficients). A total of 74 patients with chronic tonsillar pathology (24 children and 50 adults) were available for the observation along with 42 subjects having no tonsillar pathology with concomitant chronic bacterial rhinosinusitis. The control group was constituted by 25 practically healthy subjects. It was shown that the local application of imudon in the patients with the preserved function of palatine tonsils (in the absence of symptoms of chronic inflammation) produces the adequate response of the humoral and cellular immunity systems. In the patients with the simple form of chronic tonsillitis imudon therapy ensured statistically significant activation of congenital immunity including the phagocyte function and a tendency toward normalization of antibody formation. It is concluded that alteration of the function of palatine tonsils in the patients presenting with the toxico-allergic form (ТАФ-2) of chronic tonsillitis implies the necessity of surgical treatment (tonsillectomy).

An oral vaccine based on U-Omp19 induces protection against B. abortus mucosal challenge by inducing an adaptive IL-17 immune response in mice

As Brucella infections occur mainly through mucosal surfaces, the development of mucosal administered vaccines could be radical for the control of brucellosis. In this work we evaluated the potential of Brucella abortus 19 kDa outer membrane protein (U-Omp19) as an edible subunit vaccine against brucellosis. We investigated the protective immune response elicited against oral B. abortus infection after vaccination of mice with leaves from transgenic plants expressing U-Omp19; or with plant-made or E. coli-made purified U-Omp19. All tested U-Omp19 formulations induced protection against Brucella when orally administered without the need of adjuvants. U-Omp19 also induced protection against a systemic challenge when parenterally administered. This built-in adjuvant ability of U-Omp19 was independent of TLR4 and could be explained at least in part by its capability to activate dendritic cells in vivo. While unadjuvanted U-Omp19 intraperitoneally administered induced a specific Th1 response, following U-Omp19 oral delivery a mixed specific Th1-Th17 response was induced. Depletion of CD4(+) T cells in mice orally vaccinated with U-Omp19 resulted in a loss of the elicited protection, indicating that this cell type mediates immune protection. The role of IL-17 against Brucella infection has never been explored. In this study, we determined that if IL-17A was neutralized in vivo during the challenge period, the mucosal U-Omp19 vaccine did not confer mucosal protection. On the contrary, IL-17A neutralization during the infection did not influence at all the subsistence and growth of this bacterium in PBS-immunized mice. All together, our results indicate that an oral unadjuvanted vaccine based on U-Omp19 induces protection against a mucosal challenge with Brucella abortus by inducing an adaptive IL-17 immune response. They also indicate different and important new aspects i) IL-17 does not contribute to reduce the bacterial burden in non vaccinated mice and ii) IL-17 plays a central role in vaccine mediated anti-Brucella mucosal immunity.

[Treatment of chronic recurrent idiopathic pyoderma in the dog with vaccines containing bacterial antigens]

Staphylococcal vaccines are a good therapeutic alternative to the classic antibacterial treatments in dogs with chronic recurrent pyoderma without detectable underlying diseases. At the beginning of this therapy, the vaccine should be combined with other antimicrobial treatments for several weeks. Treatment success should be judged after 10, or better, 18 weeks. Differences in the production processes of the vaccine will influence the adverse effects and the success rate.

Formulation and immunogenicity studies of type III secretion system needle antigens as vaccine candidates

Bacterial infections caused by Shigella flexneri, Salmonella typhimurium, and Burkholderia pseudomallei are currently difficult to prevent due to the lack of a licensed vaccine. Here we present formulation and immunogenicity studies for the three type III secretion system (TTSS) needle proteins MxiH(Δ5), PrgI(Δ5), and BsaL(Δ5) (each truncated by five residues at its C terminus) as potential candidates for vaccine development. These antigens are found to be thermally stabilized by the presence of carbohydrates and polyols. Additionally, all adsorb readily to aluminum hydroxide apparently through a combination of hydrogen bonds and/or Van der Waals forces. The interaction of these proteins with the aluminum-based adjuvant changes with time resulting in varying degrees of irreversible binding. Peptide maps of desorbed protein, however, suggest that chemical changes are not responsible for this irreversible association. The ability of MxiH(Δ5) and PrgI(Δ5) to elicit strong humoral immune responses was tested in a murine model. When administered intramuscularly as monomers, the needle components exhibited dose dependent immunogenic behavior. The polymerized version of MxiH was exceptionally immunogenic even at low doses. The responses of both monomeric and polymerized forms were boosted by adsorption to an aluminum salt adjuvant.

[Immunotherapy and long-term chemoprophylaxis in prevention of recurrent urinary infections in women]

In clinical practice, management of urinary infections is a frequent task. Long-term prophylactic administration of small-dose chemotherapy had been shown to prevent recurrent urinary infections. Recently, an interest increases in applying immunotherapy in this indication. The authors compare immunomodulators Urovaxom and Luivac as part ofa combined immunotherapy and chemoprophylaxis regimens with small doses of fluorochinolones over 12 months in women with recurrent urinary infections. This treatment statistically significantly decreases occurrence of relapses and has been relatively well-tolerated. Unlike previous studies, we managed to isolate resistant strains producing the so-called extended-spectrum beta-lactamases (ESBL) and this may provide a signal for revision of some therapeutic approaches. In line with international recommendations, we prefer immunotherapy as comparably effective but safer treatment modality than the long-term chemoprophylaxis with fluorochinolones.

Inhibition of tumor angiogenesis by the matrix metalloproteinase-activated anthrax lethal toxin in an orthotopic model of anaplastic thyroid carcinoma

Patients with anaplastic thyroid carcinoma (ATC) typically succumb to their disease months after diagnosis despite aggressive therapy. A large percentage of ATCs have been shown to harbor the V600E B-Raf point mutation, leading to the constitutive activation of the mitogen-activated protein kinase pathway. ATC invasion, metastasis, and angiogenesis are in part dependent on the gelatinase class of matrix metalloproteinases (MMP). The explicit targeting of these two tumor markers may provide a novel therapeutic strategy for the treatment of ATC. The MMP-activated anthrax lethal toxin (LeTx), a novel recombinant protein toxin combination, shows potent mitogen-activated protein kinase pathway inhibition in gelatinase-expressing V600E B-Raf tumor cells in vitro. However, preliminary in vivo studies showed that the MMP-activated LeTx also exhibited dramatic antitumor activity against xenografts that did not show significant antiproliferative responses to the LeTx in vitro. Here, we show that the MMP-activated LeTx inhibits orthotopic ATC xenograft progression in both toxin-sensitive and toxin-resistant ATC cells via reduced endothelial cell recruitment and subsequent tumor vascularization. This in turn translates to an improved long-term survival that is comparable with that produced by the multikinase inhibitor sorafenib. Our results also indicate that therapy with the MMP-activated LeTx is extremely effective against advanced tumors with well-established vascular networks. Taken together, these results suggest that the MMP-activated LeTx-mediated endothelial cell targeting is the primary in vivo antitumor mechanism of this novel toxin. Therefore, the MMP-activated LeTx could be used not only in the clinical management of V600E B-Raf ATC but potentially in any solid tumor.

[Experience in immunomodulators application for comprehensive dental caries prevention in children and teenagers]

Prophylaxis and treatment procedures in children with different dental status was done during 9 years. Children and teenagers of 6-12 and 15-years were given teeth treatment and professional hygiene. One group of patients was additionally treated by immunomodulators imudon. It was demonstrated that improving of oral cavity hygiene and local immunity factor balance was achieved. Positive result was better in the group with imudon.

Increase of NK cells and proinflammatory monocytes are associated with the clinical improvement of diffuse cutaneous leishmaniasis after immunochemotherapy with BCG/Leishmania antigens

Diffuse cutaneous leishmaniasis (DCL) is characterized by disseminated lesions and the absence of a specific cellular immune response. Here, the immunochemotherapy outcome of a patient with DCL from Amazonian Brazil infected with Leishmania (Leishmania) amazonensis is presented. After several unsuccessful chemotherapy treatment regimens and many relapses, a monthly immunotherapy scheme of L. amazonensis PH8 plus L. (Viannia) braziliensis M2903 monovalent vaccines associated with Bacillus Calmette-Guerin (BCG) was established, one round of which also included an M2903 vaccine associated with intermittent antimonial treatment. Temporary healing of all lesions was achieved, although Leishmania skin tests were negative and interferon gamma was not detected in mononuclear cell cultures stimulated with Leishmania antigens. The frequencies of CD16 (+)CD56(+) NK cells (approximately 2x) and CD14 (+)CD16(+) proinflammatory monocytes (approximately 8x) increased in peripheral blood, and CD56 (+) lymphocytes were found infiltrating the lesions. An association between the increase of the frequency of innate immune system cells and the healing of lesions is shown, suggesting that this protocol of immunotherapy reduced the parasite load and activated NK cells and monocytes.

[Preparation of two antigens--Ag85b and HspX of Mycobacterium tuberculosis H37Rv and the effects of their co-administration with adjuvants in mice]

OBJECTIVE

To synthesize two antigens-Ag85b and HspX of Mycobacterium tuberculosis H37Rv with molecular biological methods and to observe their biologic activity after co-administration of adjuvants (aluminum and/or CpG) in mice.

METHODS

Recombinant expression plasmids pET30a-Ag85b and pET30a-HspX were constructed. The objective DNA fragments was characterized with restriction enzyme. Then the recombinant plasmids were transformed into E. coli BL-21, and two proteins were expressed by induction of isopropyl beta-D-1-thiogalactopyranoside. After purification with anion exchange column Source30, QHP, and hydrophobic chromatography column, two proteins were identified by amino acid sequencing. After the successful preparation of these two antigens, they were co-administered in mice with adjuvants of aluminum and/or CpG (Ag85b, Ag85b + Al, Ag85b + CpG, Ag85b + Al + CpG; HspX, HspX + Al, HspX + CpG, HspX + Al + CpG); one group received normal saline and served as the control. Splenic lymphocytes were isolated for enzyme-linked immunosorbent spot assay to detect the secreted specific interferon-gamma (IFN-gamma); in addition, lymphocytes proliferation test was performed to observe lymphocytes proliferation after in vitro stimulated with two antigens.

RESULTS

The purity of two proteins reached 95% after purification. The N-terminal amino acid sequence (15 aa) of the purified proteins was same as the target sequence. For Ag85b, the secreted specific IFN-gamma from isolated splenic lymphocytes after having been stimulated in vitro with Ag85b (80 microg/ml) remarkably increased in Ag85b + CpG group, Ag85b + Al group, and Ag85b + CpG + Al group; the changes were significantly different between these three groups and control group (P < 0.05). For HspX, the changes were significantly different between HspX + Al + CpG group and normal sodium group, although remarked increase of IFN-gamma was also observed in HspX group, HspX + Al group, and HspX + CpG group.

CONCLUSIONS

Ag85b and HspX were successfully expressed and purified. A cell-mediated immunity may be induced when the antigens are co-administered with adjuvants of aluminum and/or CpG in mice, indicating that the recombinant proteins are bioactive.

Bacterial extract (OM-89) specific and non specific immunomodulation in rheumatoid arthritis patients

The Escherichia Coli bacterial extract (OM-89) is used in the treatment of rheumatoid arthritis (RA). We evaluated the immunological changes induced by oral administration of OM-89 in 12 RA patients (polyclonal T cell reactivity to PHA, T cell precursor frequencies specific for OM-89 and Tetanus toxoid (TT), a control antigen and the release of Th1 (IFN-gamma, TNF-alpha), Th2 (IL-4) and T regulatory 1 cell (Tr1) (IL-10) cytokines in the supernatants of PBMC cultures. Stimulation index in response to PHA decreased at month 3 as well as T cell precursor frequencies specific for TT with similar trends for OM-89-specific T cell precursor frequencies. OM-89 induced a strong production of IL-10, a significant decrease in IL-4 production while TNF-alpha and IFN-gamma production tended to decrease during the study. Our results suggest that OM-89 has immunomodulatory properties by inducing changes in PBMC cytokines release suggestive of an induced Tr1 response to OM-89.

[Preclinical tests of Staphylococcus aureus somatic antigen as the basis for drugs for treatment of staphylococcal skin infections]

AIM

To analyze results of conducted preclinical animal tests of ointment and gel preparations based on the somatic antigen ("Somatin") of Staphylococcus aureus.

MATERIALS AND METHODS

Contents of ointment and gel as well as method of "Somatin" extraction from cytosomatin ointment are presented. Standard serum was obtained by immunization of rabbits by "Somatin". Tests for acute and chronic toxicity and sensitizing effect of cytosomatin ointment were performed. 1% gentamycin ointment was used for comparison with cytosomatin ointment and gel for treatment of pyodermia. Preparations were patented.

RESULTS

Authenticity and specific activity of ointment and gel preparations were demonstrated. Animal tests for acute and chronic toxicity of cytosomatin ointment did not reveal inflammatory reaction of skin and sclera as well as influence on biochemical parameters of the blood or abnormalities of visceral morphological structure. Assessment of sensitizing effect of cytosomatin ointment did not reveal promotion of allergy. Advantages in treatment of staphylococcal skin infections and wounds with cytosomatin ointment and gel as compared with gentamycin ointment were established.

CONCLUSION

The main immunogenic mechanism of "Somatin" substance was activation of complete phagocytosis. The character of immune response was specific. Selected optimal ratios of therapeutic doses for ointment and gel bases promote active permeation of the drug into skin that enhances its therapeutic effect. Duration of treatment with cytosomatin ointment was shortened on 5 days as compared with gentamycin ointment. Duration of treatment with cytosomatin gel was shortened on 8 days as compared with prototype.

Dendritic cell targeting of Bacillus anthracis protective antigen expressed by Lactobacillus acidophilus protects mice from lethal challenge

Efficient vaccines potentiate antibody avidity and increase T cell longevity, which confer protection against microbial lethal challenge. A vaccine strategy was established by using Lactobacillus acidophilus to deliver Bacillus anthracis protective antigen (PA) via specific dendritic cell-targeting peptides to dendritic cells (DCs), which reside in the periphery and mucosal surfaces, thus directing and regulating acquired immunity. The efficiency of oral delivery of L. acidophilus expressing a PA-DCpep fusion was evaluated in mice challenged with lethal B. anthracis Sterne. Vaccination with L. acidophilus expressing PA-DCpep induced robust protective immunity against B. anthracis Sterne compared with mice vaccinated with L. acidophilus expressing PA-control peptide or an empty vector. Additionally, serum anti-PA titers, neutralizing PA antibodies, and the levels of IgA-expressing cells were all comparable with the historical recombinant PA plus aluminum hydroxide vaccine administered s.c. Collectively, development of this strategy for oral delivery of DC-targeted antigens provides a safe and protective vaccine via a bacterial adjuvant that may potentiate mucosal immune responses against deadly pathogens.

The systemic administration of lethal toxin achieves a growth delay of human melanoma and neuroblastoma xenografts: assessment of receptor contribution

Two of the three components of anthrax toxin, protective antigen (PA) and lethal factor (LF), together known as lethal toxin (LeTx), reportedly show anti-tumor activity in melanoma in vitro and in vivo. The growth inhibitory activity of LeTx in culture was determined in nine human cancer cell lines, including melanoma, neuroblastoma and adenocarcinoma cells, as well as in human umbilical vein endothelial cells (HUVEC). The contribution of the two known PA receptor proteins, ANTXR1/TEM8 and ANTXR2/CMG2, to the sensitivity of the cells was assessed. The efficacy of LeTx was evaluated in vivo in the SK-N-AS neuroblastoma and SK-MEL-28 melanoma tumor xenograft models. Sensitivity to LeTx in vitro was observed in the neuroblastoma and colorectal adenocarcinoma cells and HUVEC, as well as melanoma cells. ANTXR1/TEM8 and ANTXR2/CMG2 protein expression studies suggested that a certain threshold of the PA receptor protein level must be met for sensitivity to LeTx to be observed. However, although the SK-N-AS neuroblastoma cells expressed the highest levels of receptor proteins and achieved the lowest IC50 in vitro (0.1 ng/ml), we observed no correlation between either the ANTXR1/TEM8 or ANTXR2/CMG2 protein levels and sensitivity to LeTx in vitro. In vivo, LeTx was an active anti-tumor agent when administered intravenously to mice bearing the human SK-N-AS or SK-MEL-28 tumor xenografts. The tumor growth delays were 6-8 days with a lower dose regimen and 14-16 days with a higher dose regimen for the two tumor models. These in vitro data suggest that LeTx may have broad therapeutic indications in cancer and the in vivo studies demonstrate that LeTx has systemic efficacy in neuroblastoma as well as melanoma. The therapeutic potential of LeTx needs to be further investigated in non-melanoma tumor models expressing the ANTXR1/TEM8 and/or ANTXR2/CMG2 protein.

Prevention and treatment of colitis with Lactococcus lactis secreting the immunomodulatory Yersinia LcrV protein

BACKGROUND & AIMS

The low calcium response V (LcrV) protein synthesized by gram-negative, pathogenic yersiniae participates in bacterial evasion of the host's innate immune response by stimulating synthesis of the anti-inflammatory interleukin (IL)-10 and preventing the activation of proinflammatory cytokines.

METHODS

We genetically engineered the food-grade bacterium Lactococcus lactis to secrete the LcrV protein from the enteropathogenic species Yersinia pseudotuberculosis. The protective and therapeutic potential of orally administered LcrV-secreting L lactis was evaluated in 2 models of acute experimental colitis (induced by trinitrobenzene sulfonic acid [TNBS] and dextran sodium sulfate [DSS], respectively) in wild-type and knockout mice.

RESULTS

Oral administration of LcrV-secreting L lactis led to active delivery of LcrV and induction of IL-10 (via a Toll-like receptor 2-dependent pathway) in the colon and prevented TNBS-induced colitis, in contrast to the L lactis control not producing LcrV. Down-regulation of tissue inflammatory markers correlated well with the reduction in damage to the colonic mucosa. In contrast, TNBS-induced colitis was not prevented in IL-10(-/-) mice pretreated with LcrV-secreting L lactis, thus showing that IL-10 is required for LcrV protection. Administration of LcrV-secreting L lactis also proved to be very effective in preventing and treating acute DSS-induced colitis.

CONCLUSIONS

LcrV-secreting L lactis decreased experimentally induced intestinal inflammation in 2 murine models of colitis. This novel approach highlights the potential of using pathogen-derived immunomodulating molecules in vivo as novel therapeutics for inflammatory bowel diseases.

[Genotypic study on the Helicobacter pylori vacA, cagA and iceA genes in the infected children in Guangzhou area]

OBJECTIVE

To investigative vacA, cagA and iceA genes dominant genotypes of Helicobacter pylori (Hp) isolated from children suffering from gastric and duodenal diseases in Guangzhou area.

METHODS

Totally 105 children who underwent gastroscopy in Guangzhou Children's Hospital were enrolled into this study. From each patient, 3 biopsy specimens from the gastric antrum were taken, one was used for rapid urease test, one for histological examination, and one for polymerase chain reaction (PCR) for detecting ureA, vacA, cagA, and iceA genes. DNA was prepared directly from the biopsy specimens from the gastric antrum using a QIAamp DNA mini kit (Qiagen, Germany) according to the manufacturer's instructions. Then 11 primers were used for detecting the genotypes including ureas, (s1, s1a, s1b, s1c, s2) and m (m1, m1T, m2) region of vacA, cagA and iceA (iceA1 and iceA2) genotypes in the 105 children. The distribution of the genotypes of Hp was analyzed.

RESULT

Among the 105 children, only 52 children were positive by the three methods, among these 52 children, 26 were boys and 26 girls. Hp vacA s1as1c/m2 was detected in 43 out of 52 children (82.7%), s1as1c/m1T in 9.6% (5/52), m region that could not betyped was 7.7% (4/52). No strains presented genotypes vacA s1b, s2, m1. The comparison of the positive ratio of vacA s1as1 c/m2 detected in the children infected with Hp and that of the other combination of signal region and middle region was statistically significantly different (P < 0.01). With regard to cagA gene, cagA(+) gene and cagA(-) gene were found in 90.4% (47/52) and 9.6% (5/52) of the children, respectively. The cagA(+) gene was more frequent in the children infected with Hp. Single iceA1 was detected in 78.8% (41/52) children, and single iceA2 was detected to be 1.9% (1/52), multiple strains infection of iceA1 and iceA2 were detected in 3.8% (2/52) children, iceA1 and iceA2 were not detected in 15.4% (8/52), the comparison of the positive ratio of iceA1 detected in the children infected with Hp and that of the other genotypes was statistically significantly different (P < 0.01).

CONCLUSION

The s1as1c/m2, cagA and iceA1 were the dominant genotypes of Hp in the children in Guangzhou area and s1as1c/m2, cagA and iceA1 were the dominant genotypes combination of Hp in the children in this area.

Development of protective immunity in a murine model of melioidosis is influenced by the source of Burkholderia pseudomallei antigens

Melioidosis is a potentially fatal disease caused by the bacterium, Burkholderia pseudomallei. The current study was carried out to determine the mechanisms involved in the development of protective immunity in a murine model of melioidosis. Following intravenous infection with B. pseudomallei, both C57BL/6 and BALB/c mice demonstrated delayed-type hypersensitivity responses and lymphocyte proliferation towards B. pseudomallei antigens, indicating the generation of B. pseudomallei-specific lymphocytes. Adoptive transfer of these lymphocytes to naïve C57BL/6 mice was demonstrated by a delayed-type hypersensitivity response. Mice were not protected from a subsequent lethal challenge with a highly virulent strain of B. pseudomallei, suggesting that a single intravenous dose of the bacterium is insufficient to induce a protective adaptive immune response. Attempts to induce resistance in susceptible BALB/c mice used repetitive low-dose exposure to live B. pseudomallei. Immune responses and resistance following subcutaneous immunization with live B. pseudomallei were compared with exposure to heat-killed, culture filtrate and sonicated B. pseudomallei antigens. Compared to heat-killed B. pseudomallei, significant protection was generated in BALB/c mice following immunization with live bacteria. Our studies also demonstrate that the type of immune response generated in vivo is influenced by the antigenic preparation of B. pseudomallei used for immunization.

Vaccine potential of influenza vectors expressing Mycobacterium tuberculosis ESAT-6 protein

We generated several attenuated recombinant influenza A vectors expressing the Mycobacterium tuberculosis early secretory antigenic target (ESAT-6) protein. The ESAT-6 protein was recently identified as one of the most promising protective antigens for cell-mediated immunity. The obtained vectors appeared to be capable of inducing ESAT-6 specific Th1 immune response in mice after intranasal immunization. We found that double immunization with two influenza vectors of different subtypes provided a significant level of protection in mice, when applied as prophylactic vaccine, as well as substantial therapeutic effect in mice with pre-established tuberculosis infection. Moreover, we found a strong synergistic effect when vaccination with Flu/ESAT-6 vectors was combined with isoniazid treatment, resulting in a dramatic reduction of bacterial load in the lungs of infected mice.

Novel bacterial delivery system with attenuated Salmonella typhimurium carrying plasmid encoding Mtb antigen 85A for mucosal immunization: establishment of proof of principle in TB mouse model

Tuberculosis (TB), the leading killer of young adults worldwide, newly affects one person every second and kills one in every 15 seconds. The recent increase of TB in developing countries has been exacerbated by many causes including pandemic HIV, war and political instability, drug resistance, and increasing poverty. Genetic immunization has emerged with tremendous potential in vaccination against TB with success in animal models with naked DNA encoding different genes such as Ag85A, Pst3, and hsp65. However, there are shortcomings in translating this success into reality in human clinical trials due to limitations at the level of delivery, quality, and quantity of DNA to be administered, which can be circumvented by using an attenuated bacteria delivery system for transgene vaccination for mucosal immunization targeting the inductive sites of the immune system. We compare this novel delivery system using an attenuated Salmonella delta aroA strain through a mucosal route with classic intramuscular DNA delivery using a potential protective antigen, Ag85A, of Mycobacterium tuberculosis in a mouse infection virulent challenge model. We show an immune response and superior protection in the mice at the level of the lungs as well as the spleen against a virulent challenge after intranasal immunization by recombinant Salmonella typhimurium carrying a eukaryotic expression plasmid encoding Ag85A rather than the classic DNA immunization and at par with the protection conferred by BCG. This study establishes the proof of principle of this system for further exploitation of this platform for vaccine development, which is being pursued for postexposure vaccine development for TB.

Systemic anthrax lethal toxin therapy produces regressions of subcutaneous human melanoma tumors in athymic nude mice

PURPOSE

Anthrax Lethal Toxin (LeTx), composed of protective antigen and lethal factor, catalytically cleaves mitogen-activated protein kinase (MAPK) kinases and inhibits the MAPK signaling pathways. The majority of metastatic melanomas possess the V599E BRAF mutation, which constitutively activates MAPK1/2 signaling. LeTx is cytotoxic to BRAF mutant melanoma cell lines in vitro, whereas most normal cells are resistant to this toxin. In this study, we determine the in vivo potency and safety of systemically administered LeTx.

EXPERIMENTAL DESIGN

A s.c. xenograft melanoma model in athymic nude mice was treated with different i.p. doses of LeTx.

RESULTS

In this study, we show that in vivo systemic LeTx treatment of s.c. xenograft melanoma tumors in athymic nude mice yields partial and complete tumor regressions with minor toxicity to mice. When animal toxicity was observed, we did not find any histologic evidence of tissue damage.

CONCLUSIONS

LeTx is one of the rare targeted agents to produce complete remissions of human melanomas in an animal model and thus warrants further preclinical development.

CpG oligonucleotides improve the protective immune response induced by the licensed anthrax vaccine

Synthetic oligodeoxynucleotides (ODN) containing unmethylated CpG motifs act as immune adjuvants, improving the response elicited by a coadministered vaccine. Combining CpG ODN with anthrax vaccine adsorbed (AVA, the licensed human vaccine) increases the speed, magnitude, and avidity of the resultant antibody response. IgG Abs against anthrax protective antigen (PA) protect mice, guinuea pigs, and rhesus macaques from infection.

Ribosomal therapy in the prophylaxis of recurrent pharyngotonsillitis in children

OBJECTIVE

Although much has been written on how to manage recurrent pharyngotonsillitis, it remains a controversial topic. The composition of normal commensal oropharynx bacteria may be disrupted by frequently using antimicrobials, by inhibiting sensitive organisms and by allowing resistant organisms to overgrowth. This may cause the recurrence of acute episodes. The aim of this study was to evaluate the efficacy of ribosomal immunotherapy in the prophylaxis of recurrent pharyngotonsillitis.

METHODS

A total of 160 children aged between 5 and 14 years with recurrent pharyngotonsillitis were ramdomized to receive either ribosomal immunotherapy (group A one tablet a day, 8 days a month for 3 months) or a placebo (group B same dosage for the same period).

RESULTS

At the end of the study, each patient treated with Immucytal presented a subjective decrease of symptoms. Compared with group B, group A experienced a significant improvement of some clinical parameters.

CONCLUSIONS

The results show that ribosomal immunotherapy causes a significant improvement of both specific and non-specific immunity and may be effective in the prophylaxis of recurrent pharyngotonsillitis and in preventing recurrences without entailing side effects or bacterial resistance.

Immunotherapy for Orthotopic Murine Bladder Cancer Using Bacillus Calmette-Guerin Recombinant Protein Mpt-64

PURPOSE

We investigated the efficacy of the recombinant bacillus Calmette-Guerin subunit protein vaccine Mpt-64 for inducing cytokine production and suppressing orthotopic bladder tumor growth in mice.

MATERIALS AND METHODS

One mycobacteria candidate gene (Mpt-64) was cloned and ligated into eukaryotic expression vectors. The induction and efficiency of Mpt-64 protein expression were detected using Western blotting. Various doses of Mpt-64 proteins were instilled intravesically 6 times in 2 weeks after intravesical implantation of MBT-2 tumor cells in chemical injured urothelium. Systemic cytokine responses, tumor growth and cumulative survival rates were monitored.

RESULTS

In vitro expression of recombinant Mpt-64 subunit protein was efficient in our system. Mice treated with 100 and 200 microg Mpt-64 subunit proteins significantly inhibited orthotopic MBT-2 tumor growth in C3H/HeN mice compared with that in control and 50 microg treatment groups in terms of the tumor taking rate, bladder tumor burden and mortality rate. Meanwhile, marked increased serum interferon-gamma with a limited but significant increase in serum interleukin-2 was observed in mice treated with 100 and 200 microg Mpt-64 proteins compared with control and 50 microg treated groups.

CONCLUSIONS

A highly immunopotent recombinant Mpt-64 subunit protein of bacillus Calmette-Guerin was produced and it elicited immune responses with a high serum interferon-gamma level, inhibited orthotopic tumor growth and prolonged survival in tumor bearing mice. Thus, intravesical immunogenic therapy using recombinant Mpt-64 protein may be an alternative bacillus Calmette-Guerin regimen for superficial bladder cancer.

Immunostimulants revisited: focus on the pharmacology of Ribomunyl

Ribomunyl is an immunostimulant that was developed and commercialized in the 1980s in France and has subsequently been made available in a large number of countries. The formulation is composed of proteoglycans from Klebsiella pneumoniae and of ribosomes from four of the most commonly encountered bacterial strains in recurrent respiratory tract infections. While it is obviously difficult to present a thorough summary of all historical data, here we revisit the mode of action of this immunostimulant and present a perspective in the context of the most recent data and hypotheses on the mechanisms of the antibacterial immune responses. We provide various examples of these mechanisms in innate immunity (phagocytosis, cell adhesion, dendritic cell maturation, Toll-like receptors, interferon production, proinflammatory cytokines, activation of natural killer cells), as well as in adaptative immunity (polyclonal activation of T and B cells, specific immunoglobulin A immune response in an integrated view of the mucosal immune system, and T helper type 1/type 2 [Th1/Th2] regulation and balance). The effect of this immunostimulant on anti-infectious responses can be explained, not only by a stimulation of the antibacterial defense directly assumed by innate immunity, but also by a stimulation of the specific (adaptative) immune response related to the activation of dendritic cells, of which the pivotal role in T-cell differentiation is already well known. This supports the potential of bacterial immunostimulants such as Ribomunyl in anti-infective therapy.

[Principles of the immune modulation therapy against papilloma virus infections]

The aim of the study was to investigate the effect of Immudone on local immune responses of cervical mucous in patients with papilloma virus cervicitis. 80 women of reproductive age with chronic cervicitis, 60 women with no signs of infection and 70 bioptates obtained from the base of vaginal section of the cervix. Colposcopic, bacterioscopic, patho-histological and immunohistochemical investigations have been performed. After using of Immudone healing of ectopia was observed in the most of cases. As a result of local application of Immudone in patients with PVI in the tissue of cervix the rate of CD4+ cells was increased, expression of receptors of interleukin-2 was increased, CD4/CD8 ratio also increased, quantity of macrophages and natural killers was increased. Local sIgA synthesis was restored.

Engineered chloroplasts as vaccine factories to combat bioterrorism

Bacillus anthracis is ideal for making biological weapons, but the licensed anthrax vaccine is unsuitable for widespread public administration. Recombinant subunit-vaccine candidates offer potential alternatives, and plant-based production systems facilitate the inexpensive bulking of target antigens. A recent report demonstrates expression of anthrax protective antigen in tobacco chloroplasts--this material is immunogenic and protective when injected into mice. Provided an economic purification scheme can be developed, this technology holds promise for an improved vaccine.

Phase II randomized, placebo-controlled trial of M. vaccae-derived protein (PVAC) for the treatment of psoriasis

The treatment effect against psoriasis of an antigen (delipidated, deglycolipidated form of M. vaccae-PVAC) was investigated. One hundred and sixty-five patients were enrolled in three arms (50 or 15 microg or placebo), each receiving a total of two intradermal injections (days 0 and 21). At week 12, a 75% decrease in psoriasis area and severity index was similar among the studied groups (13, 9 and 18%, p=0.429). The overall incidence of adverse events was significantly higher in the PVAC treated groups when compared to placebo (98.2, 87.3 and 70.9%; p<0.001) largely due to local reactions that were limited for the most part to grades 1 and 2 in severity and were self-limiting. Despite its overall safety, PVAC was not clearly indicated to be superior to placebo in the treatment of psoriasis in this study.

Correlation between lethal toxin-neutralizing antibody titers and protection from intranasal challenge with Bacillus anthracis Ames strain spores in mice after transcutaneous immunization with recombinant anthrax protective antigen

Transcutaneous immunization of mice with recombinant protective antigen (rPA) of Bacillus anthracis resulted in significantly higher lethal toxin-neutralizing antibody titers than did intramuscular injection of alum-adsorbed rPA. Immunized mice were partially protected against intranasal challenge with 235,000 (10 50% lethal doses) Ames strain B. anthracis spores. A highly significant correlation was observed between toxin-neutralizing antibody titer and survival after challenge. Future experiments with rabbits and nonhuman primates should confirm the significance of protection by this vaccine strategy.