CpG oligodinucleotides induce strong humoral and cellular responses to swine streptococcic septicemia vaccine in piglets in vivo

Oligodinucleotides containing CpG motifs (CpG ODN) are strong adjuvants for immune responses, particularly in mice, but data on humoral and cellular immune responses in piglets are scarce. In this report, using the swine streptococcus as model bacteria, CpG ODN was used as immunoadjuvants to enhance the immune responses of the piglets to swine streptococcic septicemia killed vaccine (SSSK vaccine). The titre of specific antibodies to SSSK vaccine, the proliferation of lymphocytes, SSSK-specific interferon-gamma(IFN-gamma) and IL-6, the expression of major histocompatibility complex class II (MHC-II) and CD14 of peripheral blood mononuclear cells (PBMCs) were examined to identify the immune responses of the piglets. The results were found that the above-mentioned immune responses of the piglets with CpG ODN were significantly stronger than standard immunization protocols. All these data suggested that immunostimulatory CpG ODN was promising immune enhancers for vaccination against SSSK vaccine.     

Evaluation of Poly(I:C) and combination of CpG ODN plus Montanide ISA adjuvants to enhance the efficacy of outer membrane vesicles as an acellular vaccine against Brucella melitensis infection in mice

Brucellosis is the most common zoonotic disease worldwide and still there is no vaccine for human use. The commercial animal vaccines also have major problems that limit their use. Therefore, there is a need for an effective Brucella vaccine which is multivalent and produces a good protective immunity with minimal disadvantages. Due to their heterogeneous composition and diverse functions, OMVs are promising acellular vaccine candidates against brucellosis. In the present study, the potential of Poly(I:C) or CpG ODN 1826+ Montanide ISA 70 VG adjuvant formulations were evaluated to enhance the immunity and protection levels conferred by OMVs against Brucella challenge in mice. The results indicated that both vaccine regimens were able to induce strong Th1-biased responses and confer protective levels significantly higher than REV.1 live vaccine. With regard to the results, it is concluded that OMVs in either adjuvant can be introduced as a new vaccine candidate against B. melitensis infection.     

Status and future prospects of lipid-based particulate delivery systems as vaccine adjuvants and their combination with immunostimulators

Vaccines seek to adopt pathogen-like characteristics but not true pathogen characteristics to activate the immune system without causing life-threatening disease. Vaccine formulations are therefore often particulate in nature, with dimensions comparable to pathogens, and often contain highly conserved pathogen-associated molecular patterns as adjuvants stimulating the immune system. Only a few adjuvants have been approved for human use. There is therefore an unmet medical need for the development of effective and safe adjuvants that can stimulate cellular, humoral or mucosal immunity, or combinations thereof, depending on the requirements, to prevent the specific disease. Lipid-based particulate systems are in this respect promising and versatile adjuvants that can be customized rationally towards specific vaccine targets by varying their composition. In this review, current progress in the development of lipid-based vaccine delivery systems is discussed, with a special focus on emulsions, liposomes and immune-stimulating complexes, and their combination with immunostimulatory compounds. Formulations, adjuvant mechanisms and alternative administration routes are highlighted.     

CpG oligodeoxynucleotide synergizes innate defense regulator peptide for enhancing the systemic and mucosal immune responses to pseudorabies attenuated virus vaccine in piglets in vivo

Oligonucleotides containing CpG motifs (CpG ODN) are strong adjuvants for humoral and cellular immune responses in mice, and innate defense-regulator peptides (IDRs) are known to facilitate the uptake of antigens into antigen presenting cells (APCs), but data on synergistic effects of CpG and IDRs in piglets are scarce. In this report, the combination of porcine-specific CpG ODN and HH2 (a kind of IDR which was selected for its better synergy with CpG ODN) was used as immunoadjuvant to enhance the immune responses of the newborn piglets to Pseudorabies attenuated virus (PRV) vaccine. The titers of specific antibodies and serum IgG1/IgG2 subtypes to PRV vaccine, interferon-γ (IFN-γ), tumor necrosis factor-α (TNF-α), IL-12 and IL-4 were examined to identify the immune responses of the newborn piglets. The results showed that piglets immunized intranasally (IN) and subcutaneously (SC) with PRV vaccine and CpG-HH2 complex both presented high titers of PRV-specific antibodies and IgG2 isotype, a Th1-dominated (IFN-γ and IL-12) cytokine profiles, high levels of IgA in saliva, broncheoalveolar lavage (BAL) and intestinal washings. The results suggested that, CpG-HH2 complex augmented systemic (IgG in serum) and mucosal (IgA in saliva, BAL and intestinal washings) immune responses against antigen. CpG-HH2 complex stimulated both T-helper type1 (Th1) (IgG2) and Th2 (IgA) responses when delivered IN, and IN route could induce stronger mucosal immune responses than SC route. All these data indicate that CpG-HH2 complex is a potential effective adjuvant for the PRV vaccine in newborn piglets.     

Enhanced protective efficacy and reduced viral load of foot-and-mouth disease DNA vaccine with co-stimulatory molecules as the molecular adjuvants

To improve efficacy of DNA vaccination, various approaches have been developed, including the use of plasmid expressing co-stimulatory molecules as molecular adjuvants. In this study, we investigated whether co-inoculation of a construct expressing either 4-1BBL or OX40L as the molecular adjuvant with FMDV DNA vaccine, pcD-VP1, can increase immune responses and protective efficacies. Compared to the group immunized with pcD-VP1 alone, the co-inoculation of either molecular adjuvant induced a higher ratio of IgG2a/IgG1, higher levels of expression of IFN-gamma in CD4(+) and CD8(+) T cells and antigen-specific CTL responses, and more importantly provided an enhanced protection against the live FMDV challenge in animals. Concurrently, 4-1BBL as the molecular adjuvant dramatically reduced the viral loads of FMDV in vivo after the challenge. Together, the results demonstrate that co-stimulatory molecules 4-1BBL and OX40L can enhance the antigen-specific cell-mediated responses elicited by VP1 DNA vaccine and provide an enhanced protective efficacy with the reduced viral loads.     

Intranasal administration of CpG oligonucleotides induces mucosal and systemic Type 1 immune responses and adjuvant activity to porcine reproductive and respiratory syndrome killed virus vaccine in piglets in vivo

Oligonucleotides containing CpG motifs (CpG ODN) are strong adjuvants for immune responses, particularly in mice. Recently, it has been showed that CpG ODN is a promising mucosal adjuvant in mice, but data on mucosal immune responses induced by CpG ODN in piglets are scarce. We have previously demonstrated that CpG ODN is a potent adjuvant to pseudorabies attenuated virus (PRV) vaccine when administered subcutaneously (SC) in newborn piglets. Herein, we evaluated intranasal (IN) delivery of CpG ODN with porcine reproductive and respiratory syndrome (PRRS) killed virus vaccine (PRRSV) to determine its potential as a mucosal adjuvant to a commercial vaccine. CpG ODN augmented systemic (IgG in serum, Peripheral blood mononuclear cells (PBMC) proliferation) and mucosal (IgA in feces, nasal and oral secretions) immune responses against antigen. CpG ODN stimulated both T-helper type1 (Type 1) (IgG2) and Type 2 (IgA) responses when delivered intranasally. Results from this study indicate that stimulatory CpG ODN may be effective as a mucosal adjuvant with commercial vaccine in husbandry animals.     

The antiemetic efficacy of tropisetron plus dexamethasone as compared with conventional metoclopramide-dexamethasone combination in Orientals receiving cisplatin chemotherapy: a randomized crossover trial

1We report a single-blind randomized crossover trial comparing the efficacy of tropisetron plus dexamethasone (TROPDEX) vs conventional combination of metoclopramide, dexamethasone and diphenhydramine (METDEX) in prevention of acute and delayed vomiting in Chinese patients receiving high dose cisplatin. 2Thirty-six consecutive patients with nasopharyngeal carcinoma were entered into the study, all received cisplatin at a dose range of 60–100 mg/m². Patients were randomized in the sequence of antiemetic regimens used in two consecutive cycles. 3The TROPDEX regimen consisting of tropisetron 5 mg i.v. and dexamethasone 20 mg i.v. given on day 1 of chemotherapy, followed by oral maintenance with tropisetron 5 mg daily and dexamethasone 4 mg twice daily from day 2 to 6. The METDEX regimen consisting of metoclopramide 1 mg kg⁻¹ i.v., dexamethasone 20 mg i.v. and diphenhydramine 25 mg i.v. given before chemotherapy and then 2 hourly for two more doses on day 1, followed by oral metoclopramide 20 mg 6 hourly from day 2 to 6. 4Complete control of acute vomiting was observed in 64% of patients with TROPDEX as compared with 14% with METDEX (P<0.01). While complete plus major control of acute vomiting was observed in 84% with TROPDEX as compared with 58% with METDEX. The mean vomiting episodes on day 1 were 1.4 with TROPDEX as compared with 3.5 with METDEX (P<0.01). There was, however, no significant difference between the two regimens in the control of delayed vomiting. 5When patients randomized to TROPDEX in the second cycle were compared with those with TROPDEX in the first cycle, the antiemetic efficacy was reduced, with mean acute vomiting episodes of 2 in the former compared with 0.8 in the latter (P<0.01). 6The most common adverse effect observed was headache in TROPDEX (27%) and dizziness in METDEX (40%). 7In conclusion, the antiemetic regimen TROPDEX is effective in Chinese patients receiving high dose cisplatin chemotherapy and is well tolerated. It is better than conventional METDEX regimen in the control of acute vomiting, but not in the control of delayed vomiting.     

鼠疫疫苗在食蟹猴模型中的免疫学评价

目的 通过将鼠疫耶尔森菌的F1抗原和重组V抗原组成的鼠疫疫苗免疫食蟹猴,对疫苗的免疫效果进行评价.方法 将20只食蟹猴按简单随机法分成低剂量组、高剂量组和生理盐水对照组,分别于0和2周肌内免疫,并于1剂后2周和2剂后2周采血.用ELISA检测免疫动物血清中的总IgG抗体;另外,分离外周血淋巴细胞,用酶联免疫斑点试验检测分泌IFN-γ的外周血淋巴细胞.用t检验对结果进行比较.结果 免疫后,对照组均未产生抗体,而疫苗组产生了较强的抗体应答.2剂免疫后2周,低、高剂量组的抗F1抗原IgG抗体几何平均滴度分别为(4.71±0.32)1g和(5.09±0.21)lg(t=-2.76,P＜0.05),两组的抗重组V抗原IgG抗体几何平均滴度分别为(4.75±0.52) lg和(5.12±0.58) lg(t=-1.37,P＞0.05).经F1和V抗原体外刺激产生IFN-γ的外周血淋巴细胞,细胞数均无明显增加.F1抗原刺激后,低、高剂量组分泌IFN-γ的外周血淋巴细胞数分别为(1±1)/106和(1±2)/106(t=-0.16,P＞0.05).重组V抗原刺激后,两组分别为(7±15)/106和(6±7)/106(t=0.88,P＞0.05).结论 鼠疫疫苗在食蟹猴模型中能诱导较强的体液免疫应答,但不能诱导明显的细胞免疫应答.     

Gold nanoparticles as an adjuvant: Influence of size,shape, and technique of combination with CpG on antibody production

Gold nanoparticles (GNPs) are advantageous as an adjuvant in the design of effective vaccines and in the preparation of high-affinity antibodies to haptens and complete antigens. Another method of activating immunocompetent cells with colloidal gold is to conjugate GNPs with CpG oligodeoxynucleotides (ODNs). We examined how the size and shape of GNPs and various combinations of GNPs and CpG ODNs 1826 affect the immune response. When animals were injected with a model antigen (BSA) coupled to gold nanospheres (diameters, 15 and 50 nm), nanorods, nanoshells, and nanostars, the titers of the resultant antibodies differed substantially. The antibody titers decreased in the sequence GNPs-50 nm > GNPs-15 nm > nanoshells > nanostars > nanorods > native BSA. We conclude that 50 and 15 nm gold nanospheres are the optimal antigen carrier and adjuvant for immunization. The highest titer of anti-BSA antibodies was detected in the blood serum of mice immunized simultaneously with BSA–GNP and CpG–GNP conjugates.     

In vivo efficacy of linezolid in combination with gentamicin for the treatment of experimental endocarditis due to methicillin-resistant Staphylococcus aureus

Indifference or even antagonism has mainly been reported with combinations including linezolid. The presence of in vitro antagonism is not always correlated with in vivo failure. The purpose of this study was to evaluate the in vivo activity of linezolid combined with gentamicin using a methicillin-resistant Staphylococcus aureus (MRSA) endocarditis experimental model. A human-like pharmacokinetic simulation was used for linezolid and gentamicin to improve the extrapolation of the results to human therapy. Contrary to the antagonism previously described in vitro, linezolid combined with gentamicin exhibited bactericidal activity on the two strains with a decrease of at least 4 log(10)cfu/g of vegetation compared with controls. These data suggest that linezolid plus gentamicin could be an appropriate combination for the treatment of severe MRSA infections.     

Eight new bispyridinium oximes in comparison with the conventional oximes pralidoxime and obidoxime: in vivo efficacy to protect from diisopropylfluorophosphate toxicity

In search for more efficacious reactivators of acetylcholinesterase (AChE) inhibited by organophosphorus compounds, experimental K-oximes have been synthesized which show good in vitro efficacy. However, AChE inhibition by oximes themselves (as quantified by their intrinsic IC50) is the major cause of oxime toxicity and the dose-limiting factor. To assess K-oxime efficacy in vivo, the extent of protection from mortality induced by diisopropylfluorophosphate (DFP) was quantified by Cox survival analysis and compared with that of the clinically available oximes. Oximes were administered in an equitoxic dosage, i.e. half the LD01. Best protection was conferred by K-27, reducing the relative risk of death (RR) to 16% of control RR (P < or = 0.05), which was statistically significantly better (P < or = 0.05) than all other tested oximes, except obidoxime, K-53 and K-75. The efficacy of obidoxime (RR = 0.19), K-48 (RR = 0.28), K-53 (RR = 0.22), K-74 (RR = 0.38) and K-75 (RR = 0.29) was significantly (P < or = 0.05) better than that of 2-PAM (RR = 0.62) and K-113 (RR = 0.73). No significant protective effect was observed for K-107 and K-108. Our LD50 data show that K-107, K-108 and K-113 (which strongly inhibit AChE in vitro) are in vivo markedly more toxic than all other oximes tested and can therefore only be safely administered at a low dosage which is insufficient to protect from DFP-induced mortality. Dosage calculations based on in vitro IC50 measurements may therefore in future replace in vivo LD50 determinations, thereby reducing the number of animals required.     

头孢硫脒与万古霉素联合用药治疗腹腔感染的疗效分析

目的 评价头孢硫脒(仙力素)与万古霉素联合应用时治疗甲氧西林耐药葡萄球菌及肠球菌所致腹腔感染的疗效,指导临床用药.方法 选取我院腹腔感染患者210例,随机平均分为三组,分别采用头孢硫脒十万古霉素、头孢哌酮+万古霉素及单用万古霉素治疗,比较三者治疗效果.结果 头孢硫脒与万古霉素联合应用,有效率、痊愈率及细菌消除率明显优于头孢哌酮+万古霉素及单用万古霉素,差异有统计学意义(P＜0.05),并缩短住院时间(P＜0.05),减少万古霉素用量.结论 头孢硫脒与万古霉素联合应用后,可明显减少万古霉素用量,减少细菌耐药性及副作用,疗效确切,值得临床推广使用.     

The safety and efficacy of aspirin and clopidogrel as a combination treatment in patients with coronary heart disease

The use of aspirin and clopidogrel in combination has become part of the standard clinical care of patients with coronary artery disease. The use of this combination provides significant benefits compared with the use of aspirin alone in patients with acute coronary syndromes, and in patients treated with percutaneous coronary intervention with stent placement (both bare metal and drug-eluting stents). Clinical trials have demonstrated significant efficacy of this dual therapy; however, there is the potential for significant bleeding complications from the synergistic antiplatelet effects. In total, it appears that when there is vessel injury (mechanical from perctutaneous coronary intervention or a ruptured plaque), dual antiplatelet therapy with aspirin and clopidogrel results in improved outcomes, albeit with a small but significant inherent risk of increased bleeding.     

肽咪胍啶酮联合化疗治疗难治复发性非霍奇金淋巴瘤

目的观察肽咪胍啶酮(thalidom ide商品名:反应停)联合化疗在难治复发非何杰金淋巴瘤(NHL)治疗中的疗效及不良反应。方法治疗采用化疗联合反应停。应用ELISA方法测定32例患者治疗前后血清血管内皮细胞生长因子(VEGF)浓度;用凝血因子VIII相关抗原免疫组化染色法,观察骨髓微血管密度(MVD)。根据统一疗效标准判断疗效为完全缓解(CR)、部分缓解(PR)、稳定(NC)和进展(PD)。结果32例NHL患者CR 9例,PR 12例,NC 5例,PD 4例,总有效率71.8%,无不能耐受的不良反应。MVD、VEGF治疗前后相比差异均有显著性。结论反应停联合化疗治疗复发难治NHL疗效较好,是一种有效、值得探索的新方法。     

In vivo efficacy of humanised intermittent versus continuous ceftazidime in combination with tobramycin in an experimental model of pseudomonal pneumonia

In this study, we compared the efficacy of ceftazidime (CAZ) intermittent versus continuous infusion with or without tobramycin (TOB) for the treatment of pneumonia caused by Pseudomonas aeruginosa in rabbits. Treatments were humanised and mimicked intermittent CAZ (iCAZ) (2g three times daily), continuous CAZ (cCAZ) (4g once daily (qd)) and TOB (10mg/kg qd). Minimum inhibitory concentrations (MICs) were 1mg/L and 4mg/L for TOB and CAZ, respectively. Bacterial efficacy in lungs was as follows: control, 9+/-0.6 colony-forming units (CFU)/g; TOB monotherapy, 8+/-0.5CFU/g; iCAZ monotherapy, 7.8+/-1.4CFU/g; cCAZ monotherapy, 8+/-0.4CFU/g (P = 0.005); and iCAZ+TOB, 8+/-0.5CFU/g; cCAZ+TOB, 7.2+/-0.3CFU/g (P < 0.05). Bacterial efficacy in the spleen was as follows (% sterile): control, 4+/-1.6CFU/g (0%); TOB monotherapy, 1.7+/-1.2CFU/g (60%); iCAZ monotherapy, 3.5+/-0.5CFU/g (17%); cCAZ monotherapy, 1.5+/-0.6CFU/g (75%) (P = 0.02); and iCAZ+TOB, 2.1+/-0.6CFU/g (50%); cCAZ+TOB, 1.2+/-0.3CFU/g (82%) (P < 0.05). The time the drug concentration was above the MIC (T > MIC) was 62% and 99% for iCAZ and cCAZ, respectively. We conclude that CAZ is more effective when administered continuously, especially for the sterilisation of septicaemia. A synergistic therapeutic effect of the association CAZ+TOB was observed in vivo, which can be explained by the longer T > MIC of cCAZ. These findings suggest that continuous treatment with 4g CAZ could be appropriate in patients with P. aeruginosa infections.     

Identification of novel, water-soluble, 2-amino-N-pyrimidin-4-yl acetamides as A2A receptor antagonists with in vivo efficacy

Potent adenosine hA2A receptor antagonists are often accompanied by poor aqueous solubility, which presents issues for drug development. Herein we describe the early exploration of the structure-activity relationships of a lead pyrimidin-4-yl acetamide series to provide potent and selective 2-amino-N-pyrimidin-4-yl acetamides as hA2A receptor antagonists with excellent aqueous solubility. In addition, this series of compounds has demonstrated good bioavailability and in vivo efficacy in a rodent model of Parkinson's disease, despite having reduced potency for the rat A2A receptor versus the human A2A receptor.     

The effect of co-administration of adjuvants with a nanoparticle-based genetic vaccine delivery system on the resulting immune responses.

Previously, we reported on a novel cationic nanoparticle-based DNA vaccine delivery system. In the present studies, the effects of co-administration of two well-known adjuvants, cholera toxin (CT) and lipid A (LA), with plasmid DNA (pDNA)-coated nanoparticles were investigated. Balb/C mice (n=6) were immunized with either pDNA alone (cytomegalovirus-beta-galactosidase, 5 microg) or pDNA-coated nanoparticles with either 0 or 50 microg of LA on days 0, 7, and 14 subcutaneously (s.c.), or topically on shaved skin with either pDNA (5 microg) alone or pDNA-coated nanoparticles with 0, 10, or 100 microg of CT on days 0, 6, 21, and 35. Mice were sacrificed on day 28 or day 45. Serum IgG titer, in vitro cytokine release and cell proliferation of the isolated splenocytes were determined. By the topical route, immunization of mice with 'naked' pDNA together with 10 and 100 microg of CT significantly enhanced the antigen-specific serum IgG titer by four- and 20-fold, respectively, compared to immunization with pDNA alone. Moreover, co-administration of 100 microg CT with the pDNA-nanoparticles enhanced the IgG titer by more than 300-fold over immunization with 'naked' pDNA alone with no CT. In vitro interferon-gamma (IFN)-gamma release from splenocytes isolated from mice immunized with pDNA-coated nanoparticles with CT (100 microg) was increased by three-fold over immunization with pDNA-nanoparticles without CT. Similarly, in vitro IFN-gamma release from splenocytes isolated from mice immunized with 'naked' pDNA with CT (100 microg) was increased by two-fold over immunization with 'naked' pDNA without CT. Finally, pDNA-coated nanoparticles adjuvanted with 10 microg CT resulted in the strongest splenocyte proliferation. By the s.c. route, co-administration of LA (50 microg) with pDNA resulted in more than 16-fold enhancement in IgG titer over immunization with 'naked' pDNA alone. Immunization with pDNA-coated nanoparticles with LA (50 microg) led to 16-fold enhancement in specific serum IgG titer over immunization with pDNA-coated nanoparticles with no LA, and more than 250-fold enhancement over immunization with 'naked' pDNA alone with no LA. Moreover, in vitro IFN-gamma release and proliferation by splenocytes isolated from LA co-immunized mice was also significantly enhanced. In conclusion, CT (topical) and LA (s.c.) are potential adjuvants to further enhance immune responses using a novel cationic nanoparticle-based DNA vaccine delivery system.     

Immunological reactivity to a mycobacterial fraction is associated with nonspecific suppression of immunological responsiveness in vivo

Previously reported studies revealed that spleen cells from BALB/c mice immunized against a methanol extraction residue (MER) fraction of tubercle bacilli are defective in the in vitro generation of antibodies to SRBC and in allogeneic responsiveness against C57BL spleen cells. We now show that mice repeatedly immunized with MER also exhibit a depressed capacity to respond to antigenic stimulation in vivo. Thus mice repeatedly injected with MER were impaired in their ability to react to antigenic stimulation by SRBC and by C57BL spleen cells. Impairment in the response to SRBC immunization was expressed at the level of delayed-type hypersensitivity (DTH) as well as of antibody production. The response of MER hyperimmunized mice to contact sensitization with dinitrofluorobenzene (DNFB) was not impaired, but the lymph node cells of DNFB-sensitized animals had a depressed ability to respond to in vitro stimulation by the monovalent hapten dinitrobenzene sulfonate (DNBS). The present findings indicate that extensive exposure to an immunogenic immunomodulating mycobacterial fraction can lead to a depressed responsiveness to unrelated antigenic stimulation.