Defining the role of CFTR channel blocker and ClC-2 activator in DNBS induced gastrointestinal inflammation.

In the present study, we have investigated and/or compared the role of glibenclamide, G as cystic fibrosis transmembrane conductance regulator (CFTR) inhibitor, and lubiprostone, L as chloride channel-2 (ClC-2) activator in the 2,4-dinitrobenzene sulfonic acid (DNBS)-induced gastrointestinal inflammation. GI inflammation was induced by intrarectal administration of DNBS. Rats were randomly allocated in 5 groups as sham control, distilled water + DNBS, sulfasalazine (S) + DNBS, G + DNBS, and L + DNBS. All the groups were pre-treated successively for five days before the induction of colitis. One day before and the first four days after DNBS administration various parameters were studied. Later, blood chemistry, colon's gross structure, histology, and the antioxidant load was examined. Pre-treatment with G significantly protected the change induced by DNBS concerning the change in body weight, food intake, diarrhea, occult blood in the feces, wet weight of the colon, and spleen. G because of its anti-inflammatory property down-regulated the neutrophil and WBC count and up-regulated the lymphocyte number. Moreover, G efficiently ameliorates the oxidative stress in the colon and declines the level of myeloperoxidase and malondialdehyde and up-regulated the level of superoxide dismutase and glutathione. Lubiprostone has not shown any promising effects, in fact, it causes an increase in diarrheal frequency. Our findings from this study represent that G has good potential to ameliorate GI inflammation induced by DNBS by its multiple actions including CFTR blockage and reducing the release of inflammatory markers from the MCs, anti-inflammatory and free radical scavenging property.

Chemical composition and biological activity of the essential oil from the root of Jatropha pelargoniifolia Courb. native to Saudi Arabia.

The chemical composition of the essential oil from Jatropha pelargoniifolia roots was determined via GC-FID. There were 80 compounds, representing 99.99% of the total oil constituents. Among these, 77.31% were sesquiterpenes, 14.62% were fatty acids, 7.21% were other components (i.e., phenolics, hydrocarbons, etc.), and 0.85% were monoterpenes. The major compounds in the oil were γ-eudesmol (35.31%), 5-guaien-11-ol (14.43%), epi-cedrol (8.19%), oleic acid (5.23%), bulnesol (4.45%), α-linoleic acid (4.20%), 3,4-dimethoxycinnamic acid (3.83%), palmitic acid (2.69%), isolongifolanone (2.68%), eicosane (1.41%), and cedrol (1.14%). Oxygenated sesquiterpenes were found to represent more than 50% percent of the total oil content. Moreover, the essential oil was evaluated for anti-inflammatory, antioxidant, antipyretic, and antinociceptive activities using in vivo and in vitro models. Additionally, the antioxidant potential of the oil was evaluated using various in vitro antioxidant tests, including DPPH•, ABTS•+ and FRAP. At a dose of 240 µl/kg, the oil showed anti-inflammatory (59.12%), antipyretic (37.00 ±â€¯0.11), and antinociceptive (47.58%) activities and showed significant (p < 0.001) effect as compared to a standard drug (phenylbutazone and indomethacin). These findings demonstrated that the essential oil of Jatropha pelargoniifolia root could be used as a natural source for their anti-inflammatory, antinociceptive, antipyretic, and antioxidant effects.

Effects of cigarette smoke exposure on a mouse model of multiple sclerosis.

Multiple sclerosis (MS) is an inflammatory autoimmune disease associated with genetic and environmental factors. Cigarette smoking is harmful to health and may be one of the risk factors for MS. However, there have been no systematic investigations under controlled experimental conditions linking cigarette smoke (CS) and MS. The present study is the first inhalation study to correlate the pre-clinical and pathological manifestations affected by different doses of CS exposure in a mouse experimental autoimmune encephalomyelitis (EAE) model. Female C57BL/6 mice were whole-body exposed to either fresh air (sham) or three concentrations of CS from a reference cigarette (3R4F) for 2 weeks before and 4 weeks after EAE induction. The effects of exposure on body weight, clinical symptoms, spinal cord pathology, and serum biochemicals were then assessed. Exposure to low and medium concentrations of CS exacerbated the severity of symptoms and spinal cord pathology, while the high concentration had no effect relative to sham exposure in mice with EAE. Interestingly, the clinical chemistry parameters for metabolic profile as well as liver and renal function (e.g. triglycerides and creatinine levels, alkaline phosphatase activity) were lower in these mice than in naïve controls. Although the mouse EAE model does not fully recapitulate the pathology or symptoms of MS in humans, these findings largely corroborate previous epidemiological findings that exposure to CS can worsen the symptoms and pathology of MS. Furthermore, the study newly highlights the possible correlation of clinical chemistry findings such as metabolism and liver and renal function between MS patients and EAE mice.

Immunotherapies in chronic adhesive arachnoiditis - A case series and literature review.

Chronic spinal adhesive arachnoiditis (CSAA) is a rare condition with limited therapeutic options. Surgical treatment proves effective in approximately 60% of cases. Conservative treatment options have not been extensively investigated. Here, we report the course of the disease, analyze the effect of immune treatments in patients with CSAA who were treated in the University Hospital Essen between 2015 and 2020, and conduct a literature review. Three out of four patients showed no improvement after treatment with corticosteroids, methotrexate, or plasmapheresis. All non-responders suffered from CSAA for several years, while one patient who had a disease duration of less than one month fully recovered. It is necessary to verify whether treatment at an early stage of the disease is better than treatment after chronic adhesion manifestation, as it interrupts the development of adhesions and all subsequent complications.

Sex-specific acute and chronic neurotoxicity of acute diisopropylfluorophosphate (DFP)-intoxication in juvenile Sprague-Dawley rats.

Preclinical efforts to improve medical countermeasures against organophosphate (OP) chemical threat agents have largely focused on adult male models. However, age and sex have been shown to influence the neurotoxicity of repeated low-level OP exposure. Therefore, to determine the influence of sex and age on outcomes associated with acute OP intoxication, postnatal day 28 Sprague-Dawley male and female rats were exposed to the OP diisopropylfluorophosphate (DFP; 3.4 mg/kg, s.c.) or an equal volume of vehicle (∼80 µL saline, s.c.) followed by atropine sulfate (0.1 mg/kg, i.m.) and pralidoxime (2-PAM; 25 mg/kg, i.m.). Seizure activity was assessed during the first 4 h post-exposure using behavioral criteria and electroencephalographic (EEG) recordings. At 1 d post-exposure, acetylcholinesterase (AChE) activity was measured in cortical tissue, and at 1, 7, and 28 d post-exposure, brains were collected for neuropathologic analyses. At 1 month post-DFP, animals were analyzed for motor ability, learning and memory, and hippocampal neurogenesis. Acute DFP intoxication triggered more severe seizure behavior in males than females, which was supported by EEG recordings. DFP caused significant neurodegeneration and persistent microglial activation in numerous brain regions of both sexes, but astrogliosis occurred earlier and was more severe in males compared to females. DFP males and females exhibited pronounced memory deficits relative to sex-matched controls. In contrast, acute DFP intoxication altered hippocampal neurogenesis in males, but not females. These findings demonstrate that acute DFP intoxication triggers seizures in juvenile rats of both sexes, but the seizure severity varies by sex. Some, but not all, chronic neurotoxic outcomes also varied by sex. The spatiotemporal patterns of neurological damage suggest that microglial activation may be a more important factor than astrogliosis or altered neurogenesis in the pathogenesis of cognitive deficits in juvenile rats acutely intoxicated with OPs.

Emerging peptide antibiotics with therapeutic potential.

This review covers some of the recent progress in the field of peptide antibiotics with a focus on compounds with novel or established mode of action and with demonstrated efficacy in animal infection models. Novel drug discovery approaches, linear and macrocyclic peptide antibiotics, lipopeptides like the polymyxins as well as peptides addressing targets located in the plasma membrane or in the outer membrane of bacterial cells are discussed.

Intranasal administration of regulatory dendritic cells is useful for the induction of nasal mucosal tolerance in a mice model of allergic rhinitis.

BACKGROUND: Intranasally administered dendritic cells (DCs) migrate into blood and thymus to induce immune responses. Regulatory dendritic cells (DCs) are also useful agents for allergy control. However, to the best of our knowledge, the effects of intranasal administration of regulatory DCs on allergy have not been reported until now. Therefore, we examined the effects of intranasal route of administration of CD40-silenced DCs on allergic responses and compared these with the effects of other administration routes, based on our previous findings on the inhibitory effects of CD40-silenced DCs on allergic responses. METHODS: Mice with allergic rhinitis were treated intranasally, subcutaneously, intraperitoneally, or intravenously with CD40-silenced ovalbumin (OVA)-pulsed DCs that were transfected with CD40 siRNAs and pulsed with OVA antigen. The effects of these DCs on allergic reactions and symptoms were estimated. RESULTS: Intranasal, subcutaneous, intraperitoneal, or intravenous administration of OVA-pulsed CD40-silenced DCs inhibited allergic responses and symptoms in mice. Furthermore, intranasal administration of OVA-pulsed CD40-silenced DCs significantly reduced allergic symptoms and the number of eosinophils in the nasal mucosa compared with subcutaneous, intraperitoneal, or intravenous administration of these DCs. Intranasal administration of OVA-pulsed CD40-silenced DCs resulted in significantly up-regulated IL-10, IL-35, and Foxp3 expression, and enhanced the percentage of CD11c+CD40- and CD4+CD25+ cells within the cervical lymph nodes compared to subcutaneous, intraperitoneal, or intravenous routes of administration. CONCLUSIONS: We believe that this is the first report to demonstrate that regulatory DCs infiltrate into the cervical lymph nodes after intranasal administration of these cells and that intranasal administration of regulatory DCs is more effective for the induction of tolerance in the nasal mucosa than subcutaneous, intraperitoneal, or intravenous administration.

The spectrum of primary immunodeficiencies at a tertiary care hospital in Pakistan.

BACKGROUND: Primary Immunodeficiency Disorders (PIDs) are well-known disorders in the West. but the recognition and diagnosis of these disorders is challenging in developing countries. We present the spectrum of PIDs seen at a tertiary care center in Pakistan, identified using clinical case definitions and molecular methods. METHODS: A retrospective chart review of children suspected to have PID was conducted at the Aga Khan University Hospital (AKUH) Karachi, Pakistan from 2010 to 2016. Data on demographics, clinical features, family history of consanguinity, sibling death, details of laboratory workup done for PID and molecular tests targeted panel next generation sequencing (NGS) or whole exome sequencing (WES) performed at the Geha laboratory at Boston Children's Hospital, USA was collected. The study was exempted from the Ethical Review Committee of AKUH. RESULTS: A total of 43 children visited the hospital with suspected PID during the study period. Genetic testing was performed in 31/43 (72.1%) children. A confirmed diagnosis of PID was established in 20/43 (46.5%) children. A pathogenic gene variant was identified in 17(85%) of the 20 confirmed cases (Table 1). Twelve (60%) of the confirmed cases of PID were male. The most common presenting symptom was recurrent diarrhea 11/20 (55%). The mean (±S.D) age of the cases at the time of diagnosis was 4.2 (±4.1) years. Chronic granulomatous disease (CGD) was the most common 6/20 (30%) disorder, followed by severe combined immunodeficiency (SCID) 3/20 (15%), leukocyte adhesion deficiency (LAD) 3/20 (15%), agammaglobulinemia/hypogammaglobulinemia 3/20 (15%), and Hermansky-Pudlak Syndrome (HPS) 2/20 (10%). Wiskott-Aldrich Syndrome, Immunodeficiency Centromeric Instability and Facial Anomalies Syndrome (ICF 2), Trichohepatoenteric syndrome (TRES), and C3 deficiency were each diagnosed once {1/20 (4.3%) each} (Table 1). Of these 20 confirmed cases, almost all 19/20 (95%) had a family history of consanguinity. Sibling death was reported in 5/20 (25%) of these cases. Five out of the 20 (25%) children died over the 7-year period for various reasons. CONCLUSION: PIDs are not uncommon in Pakistan; their diagnosis may be missed or delayed due to the overlapping of clinical features of PID with other diseases and a lack of diagnostic facilities. There is a need to build capacity for early recognition and diagnosis of PIDs to decrease morbidity and mortality.

Differential time-dependent transcriptional changes in the osteoblast lineage in cortical bone associated with sclerostin antibody treatment in ovariectomized rats.

Inhibition of sclerostin with sclerostin antibody (Scl-Ab) results in stimulation of bone formation on cancellous (Cn), endocortical (Ec), and periosteal (Ps) surfaces in rodents and non-human primates. With long-term dosing of Scl-Ab, the increase in bone formation is not sustained, attenuating first on Cn surfaces and later on Ec and Ps surfaces. In Cn bone, the attenuation in bone formation (self-regulation) is associated with transcriptional changes in the osteocyte (OCy) that would limit mitogenesis and are sustained with continued dosing. The expression changes in Cn OCy occur coincident with a decrease in osteoprogenitor (OP) numbers that may directly or indirectly be a consequence of the transcriptional changes in the OCy to limit OP proliferation. To characterize the Scl-Ab-mediated changes in cortical (Ct) bone and compare these changes to Cn bone, densitometric, histomorphometric, and transcriptional analyses were performed on femur diaphyses from aged ovariectomized rats. Animals were administered 50 mg/kg/wk of Scl-Ab or vehicle for up to 6 months (183 days), followed by a treatment-free period (up to 126 days). Scl-Ab increased Ct mass and area through day 183, which declined slightly when treatment was discontinued. Ps and Ec bone formation was sustained through the dosing on both Ct surfaces, with evidence of a decline in bone formation only at day 183 on the Ec surface. This is in contrast to Cn bone, where reduced bone formation was observed after day 29. TaqMan analysis of 60 genes with functional roles in the bone using mRNA isolated from laser capture micro-dissection samples enriched for Ec osteoblasts and Ct OCy suggest a pattern of gene expression in Ct bone that differed from Cn, especially in the OCy, and that corresponded to observed differences in the timing of phenotypic changes. Notable with Scl-Ab treatment was a "transcriptional switch" in Ct OCy at day 183, coincident with the initial decline in bone formation on the endocortex. A consistent sustained increase of expression for most genes in response to Scl-Ab was observed from day 8 through day 85 at the times of maximal bone formation on both Ct surfaces; however, at day 183, this increase was reversed, with expression of these genes generally returning to control values or decreasing compared to vehicle. Genes exhibiting this pattern included Wnt inhibitors Sost and Dkk1, though both had been up-regulated until the end of dosing in Cn OCy. Changes in cell cycle genes such as Cdkn1a and Ndrg1 in Ct OCy suggested up-regulation of p53 signaling, as observed in Cn OCy; however, unlike in Cn bone, p53 signaling was not associated with decreased bone formation and was absent at day 183, when bone formation began to decline on the Ec surface. These data demonstrate involvement of similar molecular pathways in Ct and Cn bone in response to Scl-Ab but with a different temporal relationship to bone formation and suggest that the specific mechanism underlying self-regulation of Scl-Ab-induced bone formation may be different between Cn and Ct bone.

Minimally invasive basilic vein transposition in the arm or forearm for autogenous haemodialysis access: A less morbid alternative to the conventional technique.

OBJECTIVE: To devise a minimally invasive, less morbid yet effective alternative technique for basilic vein transposition (BVT) in the arm/forearm and to compare perioperative outcomes with the conventional technique. PATIENTS AND METHODS: Patients undergoing BVT in the last two years (June 2013 to June 2015) were included in the study and the results were analysed. All patients were preoperatively evaluated using colour Doppler ultrasonography performed by the operating surgeon himself. For minimally invasive BVT, two or three small 1-2 cm incisions were made to completely mobilise the basilic vein, transposed in an anterolateral arm/forearm tunnel, and then anastomosed to the brachial or radial artery in the forearm and arm, respectively. The incision in the conventional technique was along the full length of the basilic vein, with the rest of the procedure remaining the same. Complications, pain, analgesic use, maturation and primary patency rates were compared between the techniques. RESULTS: In all, 30 patients underwent minimally invasive BVT and 34 patients underwent conventional BVT, with mean age of 52 and 55 years, respectively. The complications of wound haematoma (one vs four) and wound infection/dehiscence (two vs six) were less common in the minimally invasive BVT group compared to the conventional group. The analgesic requirement and visual analogue scale pain score was significantly less in the minimally invasive BVT group. All other variables assessed, such as maturation and primary patency rate at 1 year, were not significantly different between the groups. CONCLUSION: Minimally invasive dissection of the basilic vein for vascular access transposition is a safe, reliable procedure with patency and functional outcomes comparable with those of conventional BVT.

Functional Specialty of CD40 and Dendritic Cell Surface Lectins for Exogenous Antigen Presentation to CD8(+) and CD4(+) T Cells.

Dendritic cells (DCs) are major antigen-presenting cells that can efficiently prime and cross-prime antigen-specific T cells. Delivering antigen to DCs via surface receptors is thus an appealing strategy to evoke cellular immunity. Nonetheless, which DC surface receptor to target to yield the optimal CD8(+) and CD4(+) T cell responses remains elusive. Herein, we report the superiority of CD40 over 9 different lectins and scavenger receptors at evoking antigen-specific CD8(+) T cell responses. However, lectins (e.g., LOX-1 and Dectin-1) were more efficient than CD40 at eliciting CD4(+) T cell responses. Common and distinct patterns of subcellular and intracellular localization of receptor-bound αCD40, αLOX-1 and αDectin-1 further support their functional specialization at enhancing antigen presentation to either CD8(+) or CD4(+) T cells. Lastly, we demonstrate that antigen targeting to CD40 can evoke potent antigen-specific CD8(+) T cell responses in human CD40 transgenic mice. This study provides fundamental information for the rational design of vaccines against cancers and viral infections.

Evaluation of cetuximab as a candidate for targeted α-particle radiation therapy of HER1-positive disseminated intraperitoneal disease.

Although the epidermal growth factor receptor (EGFR), also known as HER1, has been studied for over a decade, it continues to be a molecule of great interest and focus of investigators for development of targeted therapies. The marketed monoclonal antibody cetuximab binds to HER1, and thus might serve as the basis for creation of imaging or therapies that target this receptor. The potential of cetuximab as a vehicle for the delivery of α-particle radiation was investigated in an intraperitoneal tumor mouse model. The effective working dose of 10 µCi of (212)Pb-cetuximab was determined from a dose (10-50 µCi) escalation study. Toxicity, as indicated by the lack of animal weight loss, was not evident at the 10 µCi dose of (212)Pb-cetuximab. A subsequent study demonstrated (212)Pb-cetuximab had a therapeutic efficacy similar to that of (212)Pb-trastuzumab (p = 0.588). Gemcitabine given 24 h prior to (212)Pb-cetuximab increased the median survival from 174 d to 283 d, but carboplatin suppressed the effectiveness of (212)Pb-cetuximab. Notably, concurrent treatment of tumor-bearing mice with (212)Pb-labeled cetuximab and trastuzumab provided therapeutic benefit that was greater than either antibody alone. In conclusion, cetuximab proved to be an effective vehicle for targeting HER1-expressing tumors with α-radiation for the treatment of disseminated intraperitoneal disease. These studies provide further evidence that the multimodality therapy regimens may have greater efficacy and benefit in the treatment of cancer patients.

Immunotherapeutic intervention with oncolytic adenovirus in mouse mammary tumors.

The goal is to elucidate the immune modulating activity of an adenovirus (Adv) vector which showed therapeutic activity in human clinical trials. The oncolytic adenovirus (Adv/CD-TK) expressing two suicide genes was tested in two HER2/neu positive BALB/c mouse mammary tumor systems: rat neu-induced TUBO and human HER2-transfected D2F2/E2. Intra-tumoral (i.t.) Adv/CD-TK injection of TUBO tumor plus systemic prodrug therapy showed limited antitumor activity, not exceeding that by the virus itself. Antibody (Ab) to the virus was induced in Adv-/Luc-treated mice, to coincide with the loss of transgene expression. Low replication activity of adenoviruses in rodent cells may limit viral persistence. Host immunity against Adv or Adv-infected cells further mutes suicide gene activity. Treatment of TUBO tumors with Adv/CD-TK alone, however, induced neu-specific Ab responses. Treatment with Adv/CD-TK/GM (Adv/GM) that also expressed mouse granulocyte macrophage colony stimulating factor (GM-CSF), but without prodrug treatment, delayed tumor growth, enhanced anti-neu Ab production and conferred complete protection against secondary tumor challenge. D2F2/E2 tumor-bearing mice showed decreased tumor growth following i.t. Adv/GM treatment and they generated greater HER2-specific T-cell responses. These data suggest that i.t. injection of Adv itself induces immune reactivity to tumor-associated antigens and the encoded cytokine, GM-CSF, amplifies that immune response, resulting in tumor growth inhibition. Incorporation of suicide gene therapy did not improve the efficacy of Adv therapy in this mouse mammary tumor system. Oncolytic adenoviral therapy may be streamlined and improved by substituting the suicide genes with immune modulating genes to exploit tumor immunity for therapeutic benefit.

A tetravalent bispecific TandAb (CD19/CD3), AFM11, efficiently recruits T cells for the potent lysis of CD19(+) tumor cells.

To harness the potent tumor-killing capacity of T cells for the treatment of CD19(+) malignancies, we constructed AFM11, a humanized tetravalent bispecific CD19/CD3 tandem diabody (TandAb) consisting solely of Fv domains. The molecule exhibits good manufacturability and stability properties. AFM11 has 2 binding sites for CD3 and 2 for CD19, an antigen that is expressed from early B cell development through differentiation into plasma cells, and is an attractive alternative to CD20 as a target for the development of therapeutic antibodies to treat B cell malignancies. Comparison of the binding and cytotoxicity of AFM11 with those of a tandem scFv bispecific T cell engager (BiTE) molecule targeting the same antigens revealed that AFM11 elicited more potent in vitro B cell lysis. Though possessing high affinity to CD3, the TandAb mediates serial-killing of CD19(+) cells with little dependence of potency or efficacy upon effector:target ratio, unlike the BiTE. The advantage of the TandAb over the BiTE was most pronounced at lower effector:target ratios. AFM11 mediated strictly target-dependent T cell activation evidenced by CD25 and CD69 induction, proliferation, and cytokine release, notwithstanding bivalent CD3 engagement. In a NOD/scid xenograft model, AFM11 induced dose-dependent growth inhibition of Raji tumors in vivo, and radiolabeled TandAb exhibited excellent localization to tumor but not to normal tissue. After intravenous administration in mice, half-life ranged from 18.4 to 22.9 h. In a human ex vivo B-cell chronic lymphocytic leukemia study, AFM11 exhibited substantial cytotoxic activity in an autologous setting. Thus, AFM11 may represent a promising therapeutic for treatment of CD19(+) malignancies with an advantageous safety risk profile and anticipated dosing regimen.

Comparison of virulence between the Yersinia pestis Microtus 201, an avirulent strain to humans, and the vaccine strain EV in rhesus macaques, Macaca mulatta.

Our previous study has demonstrated that Yersinia pestis Microtus 201 is a low virulent strain to the Chinese-origin rhesus macaques, Macaca mulatta, and can protect it against high dose of virulent Y. pestis challenge by subcutaneous route. To investigate whether the Y. pestis Microtus 201 can be used as a live attenuated vaccine candidate, in this study its intravenous virulence was determined and compared with the live attenuated vaccine strain EV in the Chinese-origin rhesus macaque model. The results showed that the Chinese-origin rhesus macaques can survive intravenous infection with approximately 10(9) CFU of the Y. pestis Microtus 201, but all the animals succumbed to 10(10) CFU of intravenous infection. By contrast, all the animals survive intravenous infection with 10(10) CFU of the vaccine EV. Post-mortem examination showed multiple areas of severe abscess in the lungs of the dead animals infected with 10(10) CFU of the Y. pestis Microtus 201, whereas histopathology observation, microbiological examination and immunohistochemistry staining showed that the Y. pestis Microtus 201 also invaded hearts, livers, spleens, kidneys and lymph nodes and caused different degrees of pathological changes in these organs. These results indicated that the Y. pestis Microtus 201 is indeed low virulent to monkeys, but it is more virulent than the vaccine EV when administered by intravenous route. The Y. pestis Microtus 201 mainly attack the lungs when administered by intravenous infection, which may be the leading cause of animal death.

Neoadjuvant immunotherapy with chitosan and interleukin-12 to control breast cancer metastasis.

Metastasis accounts for approximately 90% of breast cancer-related deaths. Therefore, novel approaches which prevent or control breast cancer metastases are of significant clinical interest. Interleukin-12 (IL-12)-based immunotherapies have shown promise in controlling metastatic disease, yet modest responses and severe toxicities due to systemic administration of IL-12 in early trials have hindered clinical application. We hypothesized that localized delivery of IL-12 co-formulated with chitosan (chitosan/IL-12) could elicit tumor-specific immunity and provide systemic protection against metastatic breast cancer while minimizing systemic toxicity. Chitosan is a biocompatible polysaccharide derived primarily from the exoskeletons of crustaceans. In a clinically relevant resection model, mice bearing spontaneously metastatic 4T1 mammary adenocarcinomas received intratumoral injections of chitosan/IL-12, or appropriate controls, prior to tumor resection. Neoadjuvant chitosan/IL-12 immunotherapy resulted in long-term tumor-free survival in 67% of mice compared to only 24% or 0% of mice treated with IL-12 alone or chitosan alone, respectively. Antitumor responses following chitosan/IL-12 treatment were durable and provided complete protection against rechallenge with 4T1, but not RENCA renal adenocarcinoma, cells. Lymphocytes from chitosan/IL-12-treated mice demonstrated robust tumor-specific lytic activity and interferon-γ production. Cell-mediated immune memory was confirmed in vivo via clinically relevant delayed-type hypersensitivity (DTH) assays. Comprehensive hematology and toxicology analyses revealed that chitosan/IL-12 induced transient, reversible leukopenia with no changes in critical organ function. Results of this study suggest that neoadjuvant chitosan/IL-12 immunotherapy prior to breast tumor resection is a promising translatable strategy capable of safely inducing to tumor-specific immunity and, in the long term, reducing breast cancer mortality due to progressive recurrences.

Live attenuated pre-erythrocytic malaria vaccines.

Although recent control measures have significantly reduced malaria cases and deaths in many endemic areas, an effective vaccine will be essential to eradicate this parasitic disease. Malaria vaccine strategies developed to date focus on different phases of the parasite's complex life cycle in the human host and mosquito vector, and include both subunit-based and whole-parasite vaccines. This review focuses on the 3 live-attenuated malaria vaccination strategies that have been tested in humans to date, and discusses their progress, challenges and the immune correlates of protection that have been identified.

Truncated abrin A chain expressed in Escherichia coli: a promising vaccine candidate.

Abrin toxin (AT) is a highly potent toxin, and is classified as one of the most important biological warfare and bioterrorism agents. There is currently no approved vaccine for AT. Therefore, the development of an effective vaccine is important in the prevention of intoxication by abrin. In this study, five vectors containing different gene of truncated abrin toxin A chain (tATA) fragments were constructed, and two of them (tATA1(1-126), tATA4(1-188)) were successfully expressed as a soluble form in E.coli strain. Both of the two tATA retained most of their immunogenicity with either low or no toxic effects as determined by both in vitro and in vivo assays. They were used to immunize BALB/c mice three times at an interval of three weeks apart. As a result, the tATA1 can elicite 80% protective efficacy against i.p. challenge of 5×LD50 of abrin, and the tATA4 provides a better protection, which can elicite 100% protective efficacy against intraperitoneal challenge of 40×LD50 of abrin. The superior fragment (tATA4(1-188)) should be considered as a promising vaccine candidate for further investigations.

IMA901: a multi-peptide cancer vaccine for treatment of renal cell cancer.

Despite a major improvement in the treatment of advanced kidney cancer by the recent introduction of targeted agents such as multi-kinase inhibitors, long-term benefits are still limited and a significant unmet medical need remains for this disease. Cancer immunotherapy has shown its potential by the induction of long-lasting responses in a small subset of patients, however, the unspecific immune interventions with (high dose) cytokines used so far are associated with significant side effects. Specific cancer immunotherapy may circumvent these problems by attacking tumor cells while sparing normal tissue with the use of multi-peptide vaccination being one of the most promising strategies. We here summarize the clinical and translational data from phase I and II trials investigating IMA901. Significant associations of clinical benefit with detectable T cell responses against the IMA901 peptides and encouraging survival data in treated patients has prompted the start of a randomized, controlled phase III trial in 1st line advanced RCC with survival results expected toward the end of 2015. Potential combination strategies with the recently discovered so-called checkpoint inhibitors are also discussed.