Clinicopathological and immunological studies on toxoids vaccine as a successful alternative in controlling clostridial infection in broilers

The present study was conducted to evaluate the efficacy and safety of three vaccination regimes of Clostridium perfringens (C. perfringens) type A, C and combined A&C toxoids based on their clinical signs and immunological effects. The vaccines were administered two times at two weeks interval (7 & 21 days old), then the birds were challenged (35 days old) with virulent strains of C. perfringens type A, C and combined A&C. Blood samples were taken one week after the first and second vaccination as well as after challenge. The evaluated parameters in this study included: clinical signs, gross intestinal lesions, complete blood count (CBC), serum protein, liver profiles, and enzyme-linked immunosorbent assay (ELISA) test for detecting serum antibody titers. The results revealed that immunization of broilers with C. perfringens type A, C and combined A&C toxoids resulted in a significant decrease in numbers of chickens with intestinal lesions particularly with the A&C toxoids vaccine. Results of the CBC values were significantly increased in all treated groups and challenged groups. Total leukocytic count decreased in challenged non vaccinated group while increased in challenged vaccinated birds. Results of biochemical assays implicated that there were a significant increase in serum protein and liver profiles. ELISA results explored a significant increase in antibody titers after immunization of broilers with C. perfringens type A, C and combined A&C toxoids particularly after the second dose of vaccination. We concluded that immunization of broilers with toxoid vaccines particularly the combined type A & C is safe, well-tolerated and can protect broiler chickens against necrotic enteritis particularly after the second booster dose of the vaccine.     

Fecal IgA antibody responses after oral poliovirus vaccination in infants and elder children

We investigated fecal IgA antibody responses after oral polyvalent poliovirus vaccination. Infants were given vaccines twice with an interval of 6 weeks. Specific IgA antibodies in the feces were determined by enzyme-linked immunosorbent assay, and viruses were isolated in tissue cultures. We found that, after the first vaccination, antibody responses seemed to be elicited only against the serotypes of isolated viruses. After the second vaccination, however, antibodies were detected to all three serotypes with higher titers, suggesting that the first vaccination induced the immunologic memory. The IgA antibodies had virus-neutralizing activity, and existed in the feces as both intact 11S and fragmented 4S molecules. Next, children were given the third vaccination 3 or 9 years later. Fecal IgA antibody responses were found to be poorer in elder children, while they responded with high serum neutralization titers. The secretory IgA memory seemed to last much shorter the serum IgG memory.     

Booster vaccination with live attenuated Vibrio anguillarum elicits strong protection despite weak specific antibody response in zebrafish

A live attenuated Vibrio anguillarum vaccine was recently established in the laboratory that induced immunoprotection against vibriosis in zebrafish, Danio rerio. To improve immunogenicity, the effects of different booster vaccination regimens were investigated using bath‐vaccination in a zebrafish model. Zebrafish receiving booster doses at 2 weeks or at both 2 and 4 weeks after primary vaccination were better protected in comparison to fish that received a single vaccination. In addition, the booster vaccination induced a prolonged specific antibody response. No correlation between a weak specific antibody response and a strong protection was observed, indicating that the booster vaccination could enhance the affinity of Immunoglobulin M (IgM) rather than the amount. Moreover, changes in the immune‐related gene expression of the booster‐vaccinated group suggested that the booster enhanced the adaptive immune responses.     

Immune evasion mechanisms in colorectal cancer liver metastasis patients vaccinated with TroVax (MVA-5T4)

We have recently reported the results of a phase II trial in which two TroVax [modified vaccinia ankara (MVA) encoding the tumour antigen 5T4] vaccinations were given to patients both pre- and post-surgical resection of liver metastases secondary to colorectal cancer (CRC). 5T4-specific cellular responses were assessed at the entry and 2 weeks after each vaccination by proliferation of fresh lymphocytes and ELISA for antibody responses; 18 from the 19 CRC patients mounted a 5T4-specific cellular and/or humoral response. Here, we present a comparison of individual and between patient responses over the course of the treatments using cryopreserved peripheral blood mononuclear cells (PBMC) samples from the baseline until after the fourth vaccination at 14 weeks. Assays used were proliferation assay with 5T4-Fc fusion protein, overlapping 32mer 5T4 peptides, MVA-LacZ and MVA-5T4 infected autologous monocytes. Responses to 5T4 protein or one or more peptide pools were pre-existing in 12/20 patients and subsequently 10 and 12 patients showed boosted and/or de novo responses, respectively. Cumulatively, 13/20 patients showed proliferative responses by week 14. We also assessed the levels of systemic T regulatory cells, plasma cytokine levels, phenotype of tumour-infiltrating lymphocytes including T regulatory cells and tumour HLA class I loss of expression. More than half of the patients showed phenotypes consistent with relative immune suppression and/or escape highlighting the complexity of positive and negative factors challenging any simple correlation with clinical outcome.     

Effects of conjugated linoleic acids on growth performance,serum lysozyme activity,lymphocyte proliferation,and antibody production in broiler chicks

Abstract

This study was conducted to investigate the effect of dietary conjugated linoleic acids (CLA) on growth performance and immune responses in broiler chicks. A total of 240 day-old Arbor Acre male broiler chicks were randomly allotted into four dietary treatments with different inclusion levels of CLA (0, 2.5, 5.0 or 10.0 g/kg) for six weeks. Growth performance, peripheral blood lymphocyte (PBL) proliferation, lysozyme activity, phagocytic activity (carbon clearance) and serum antibody titers against Newcastle disease virus (NDV) vaccine were examined. There were no significant differences in growth performance among treatments (p > 0.05). Chicks fed CLA diets produced more lysozyme activity in serum than the control group at 2 and 6 weeks of age (p < 0.05). Dietary CLA enhanced the PBL proliferation in response to concanavalin A (ConA) at the age of 42 d (p < 0.05). Phagocytic ability was also affected by dietary CLA and chicks fed CLA diets had faster carbon clearance rate (p < 0.05), but antibody titers to NDV was not influenced by dietary CLA. The results of the study suggested that dietary CLA could enhance innate and cellular immune response in broiler chicks, and not affect the growth performance.     

Changes in blastogenic responses and antibody titers of mice infected with Toxoplasma gondii]

This study was performed to observe the cell-mediated and humoral immune responses in mice which were infected with Beverley, Fukaya and ME49 strain of Toxoplasma gondii, respectively. The blastogenic responses of splenocytes using [3H]-thymidine and serum antibody titers were measured weekly up to 10 weeks after infection. The blastogenic responses of splenocytes treated with concanavalin A and Toxoplasma lysate were significantly declined in the 3 strain groups as compared with the non-infected group (p less than 0.05), however lipopolysaccharide-treated blastogenic responses were not significantly different between infected and non-infected groups. The serum IgG antibody titers in the three infected groups increased from 2 weeks after infection, and the serum IgM antibody titers increased until 4 weeks after infection. No significant differences were revealed in blastogenic responses and serum antibody titers among the 3 groups. The present study suggested that cell-mediated immune responses were involved in T. gondii infected mice and blastogenic responses of T lymphocytes were inhibited in acute T. gondii infection.     

A novel bivalent Pasteurellosis-RHD vaccine candidate adjuvanted with Montanide ISA70 protects rabbits from lethal challenge

In the present study, a bivalent vaccine against Pasteurella multocida and rabbit hemorrhagic disease virus (RHDV) was formulated with Montanide™ ISA70 oil adjuvant (Seppic, Paris, France). Its efficacy was evaluated and compared to similar monovalent preparations and commercially available monovalent vaccines. White new Zeeland rabbit groups (n = 10) received 2 successive doses of the tested vaccines and were challenged 2 weeks after 2nd dose with Pasteurella multocida and RHDV or either pathogens according to their vaccination schedule. Challenged not-vaccinated group of rabbits (n = 10) was included as a control. The bivalent and monovalent ISA70 preparations were found stable, safe, sterile, pure and of low viscosity. Group 3 (GP3) which received bivalent vaccine showed the highest antibody geometric mean titers against Pasteurella multocida and RHDV evaluated by ELISA and hemagglutination inhibition (HI) respectively. Following virulent challenge; Gp3 rabbits were 90% protected from challenge over other groups that showed 80% protection. Detection of either pathogen in the livers of dead and euthanized rabbits had failed except for non-vaccinated controls. The bivalent vaccine candidate was fully protective. Immunization against both pathogens can be achieved by single vaccination.     

Vaccine therapy for ocular herpes simplex virus (HSV) infection: periocular vaccination reduces spontaneous ocular HSV type 1 shedding in latently infected rabbits.

Periocular vaccination of rabbits with preexisting herpes simplex virus type 1 (HSV-1) latent infection with recombinant HSV-2 glycoproteins B and D (gB2 and gD2) plus adjuvant significantly reduced ocular viral shedding. Rabbits were infected in both eyes with HSV-1 strain McKrae. Following HSV-1 infection and the establishment of latency (28 days postinfection), rabbits were given a periocular subconjunctival vaccination three times at 3-week intervals. Beginning 3 weeks after the final vaccination, tear films were collected daily and cultured to detect the presence of HSV-1 and determine the spontaneous HSV-1 ocular shedding rates. Periocular vaccination increased the mean HSV-1 serum neutralizing antibody titer to fivefold above that seen in mock-vaccinated latently infected rabbits. gB enzyme-linked immunosorbent assay (ELISA) antibody titers were increased approximately 8-fold, and gD ELISA antibody titers were increased 60-fold. These increases were all statistically significant (P < 0.0001). In two independent experiments, vaccination reduced the spontaneous shedding rate by approximately 2.5-fold (P < 0.0004). In addition, the percentage of eyes that never shed virus during the 6 week postvaccination test period increased threefold (20% in controls versus 60% in vaccinated animals; P < 0.007). These results show that spontaneous ocular shedding of HSV-1 in latently infected rabbits can be significantly reduced by local periocular vaccination. This is the first report in any animal model of a successful therapeutic vaccine against recurrent HSV-1 ocular shedding. These results support the concept that development of a therapeutic vaccine for ocular HSV-1 recurrence in humans is possible.     

Assessment of Human Immune Response to Mutans Streptococcal Glucosyltransferase Peptides Selected by MHC Class II Binding Probability

Dental decay is a major public health challenge, causing substantial social and economic burdens. In animals, vaccination against mutans streptococci, the causative organism, interferes with dental caries. The mutans streptococcal glucosyltransferase (GTF) has been effectively used as a protein antigen in experimental dental caries vaccines. Compared to whole proteins, peptide subunits can focus immune responses on protective epitopes, and not on potentially harmful cross reactive antigens. In the past we selected peptide subunits of GTF for vaccine discovery based on putative functional significance and conservation of GTF primary structure. To focus on the immunogenicity of peptides, we estimated the probability of MHC class II binding. Twenty 20-mer linear GTF peptides were synthesized on this basis and their immunoreactivity explored. Significant human peripheral blood mononuclear cell (PBMC; n = 12) proliferation was observed in response to amino acids (AA) 502–521 (peptide 7), located in the catalytic domain of GTF. Human serum (n = 36) antibody reactivity was observed to AA 438–457 (peptide 5), AA 502–521 (peptide 7), and AA 1376–1395 (peptide 16). Whole saliva mutans streptococcal levels were used as markers of mutans infection, and dental examinations to determine existing and historic caries (DMFS score) were performed. DMFS scores correlated with mutans streptococcal counts, but not with immune responses. We have identified peptides with projected avid MHC-binding activity that reacted with human PBMC and serum antibody, implying that these peptides are immunogenic and may be of significance in a subunit dental caries vaccine.     

Effects of delivery method on serological responses of bighorn sheep to a multivalent Pasteurella haemolytica supernatant vaccine

The safety and efficacy of a remotely delivered multivalent Pasteurella haemolytica supernatant vaccine (serotypes A2 and T10) were examined in captive Rocky, Mountain bighorn sheep (Ovis canadensis canadensis). Twenty bighorn sheep were grouped according to baseline leukotoxin neutralizing antibody titers (< or =2 or >2 log2(-1)) and vaccination history (previously vaccinated or unvaccinated). Within these groups, animals were randomly assigned to one of two delivery treatments: hand injection (control) or biobullet implantation. All bighorns received a single dose from the same lot of vaccine (n = 10/treatment); four additional animals were injected intramuscularly with 0.9% saline as unvaccinated sentinels. Mild, transient lameness one day after hand injection or biobullet implantation was the only adverse effect. Serum neutralizing antibody titers to P. haemolytica leukotoxin differed between delivery treatments (P = 0.009) and among baseline titer/vaccination history groups (P = 0.013). Neutralizing titers were higher among hand-injected bighorns. Although neutralizing titers were lower among implanted bighorns than hand-injected controls at 1 wk (P = 0.002) and 2 wk (P = 0.021) after vaccination, seroconversion rates in response to implantation (6/10) and hand injection (9/10) did not differ (P = 0.303). Agglutinating antibody titers to T10 were high and did not vary over time or between delivery treatments. Agglutinating antibody titers to A2 in the hand-injected controls were not different (P > or = 0.07) than those in bighorns vaccinated with biobullet implantation. These data demonstrate that although hand injection elicits higher absolute titers, biobullet implantation may also stimulate effective antibody responses to P. haemolytica supernatant vaccine. Further evaluation of biobullet vaccination against pneumonic pasteurellosis in free-ranging populations of wild bighorn sheep is warranted.     

Impaired Antibody Response to Influenza Vaccine in HIV-Infected and Uninfected Aging Women Is Associated with Immune Activation and Inflammation

Background

Aging and HIV infection are independently associated with excessive immune activation and impaired immune responses to vaccines, but their relationships have not been examined.

Methods

For selecting an aging population we enrolled 28 post-menopausal women including 12 healthy volunteers and 16 HIV-infected women on antiretroviral treatment with <100 HIV RNA copies/ml. Antibody titers to trivalent influenza vaccination given during the 2011-2012 season were determined before and 4 weeks after vaccination.

Results

Seroprotective influenza antibody titers (≥1:40) were observed in 31% HIV⁺ and 58% HIV-uninfected women pre-vaccination. Following vaccination, magnitude of antibody responses and frequency of seroprotection were lower in HIV⁺ (75%) than in HIV^– (91%) women. Plasma IL-21, the signature cytokine of T follicular helper cells (Tfh), and CD4 T cell IL-21R were upregulated with seroconversion (≥4 fold increase in antibody titer). Post-vaccine antibody responses were inversely correlated with pre-vaccination plasma TNFα levels and with activated CD4 T cells, including activated peripheral (p)Tfh. Plasma TNFα levels were correlated with activated pTfh cells (r=0.48, p=0.02), and inversely with the post-vaccination levels of plasma IL-21 (r=-0.53, p=0.02). In vitro TNFα blockade improved the ability of CD4 T cells to produce IL-21 and of B cells to secrete immunoglobulins, and addition of exogenous IL-21 to cell cultures enhanced B cell function. Higher frequencies of activated and exhausted CD8 T and B cells were noted in HIV⁺ women, but these markers did not show a correlation with antibody responses.

Conclusions

In aging HIV-infected and uninfected women, activated CD4 and pTfh cells may compromise influenza vaccine-induced antibody response, for which a mechanism of TNFα-mediated impairment of pTfh-induced IL-21 secretion is postulated. Interventions aimed at reducing chronic inflammation and immune activation in aging, HIV-infected patients may improve their response to vaccines.     

Yellow Fever Vaccine: Direct Challenge of Monkeys Given Graded Doses of 17D Vaccine

In rhesus monkeys a wide dosage range of 17D yellow fever (YF) vaccine extending to a level even below that recommended for vaccination of man elicited an immune response providing solid protection to challenge with virulent YF virus. Forty-three of 45 monkeys vaccinated with 10(2.3) or greater weanling mouse mean lethal doses of 17D vaccine were resistant to challenge 20 weeks later with virulent Asibi strain YF virus. Monkeys given graded doses of lesser amounts of vaccine were progressively more susceptible to challenge. With a vaccine dose >/= 10(2.3) weanling mouse mean lethal doses, plaque neutralization (PN) seroconversion rates were 90% or greater, whereas hemagglutination-inhibiting (HI) and complement-fixing (CF) seroconversion rates were unrelated to vaccine dosage and were generally in the range of 20 to 80%. Ninety-six percent (51 of 54) of immune monkeys had PN titers >/=0.7 log(10) (fivefold) neutralization index as compared to approximately 55 to 65% who showed HI or CF titers >/=2 log(2) (fourfold) neutralization index. After challenge with Asibi strain YF virus, antibody titers of all three tests increaed equally. In rhesus monkeys PN antibody titers were well correlated with YF immunity, whereas HI and CF antibody titers were not.     

The Incidence of Graves’ Hyperthyroidism Before and After COVID-19 Messenger RNA Vaccination

ObjectiveCase reports of postvaccine early-onset Graves’ hyperthyroidism (PVGD) after the administration of COVID-19 vaccination have emerged. Our aim was to investigate whether the incidence of Graves’ hyperthyroidism (GD) has increased after the introduction of COVID-19 vaccination.MethodsWe compared the incidence of new-onset GD at a single academic center during 2 periods: December 2017 to October 2019 and December 2020 to October 2022, ie, before and after the implementation of COVID-19 vaccinations. We defined PVGD as laboratory-confirmed hyperthyroidism and GD within 4 weeks after the vaccination or clear onset of symptoms of thyrotoxicosis within 4 weeks of vaccination with evidence of hyperthyroidism and GD within 3 months.ResultsDuring the prevaccination period, 803 patients carried diagnoses of GD, and of these, 131 were new. During the postvaccination period, 901 patients carried diagnoses of GD, and of these, 138 were new. There was no statistically significant difference in the incidence of GD (P = .52), age at onset, gender, or race between the 2 groups. Twenty-four of 138 newly diagnosed patients in the post–COVID-19 group met the criteria for PVGD. The median free T4 was higher, but this was not statistically significant (3.9 vs 2.5 ng/dL, P = .05). There were no differences in age, gender, race, antibody titers, or type of vaccination between PVGD and controls.ConclusionThere was no increase in new-onset GD after COVID-19 vaccination. Median free T4 was higher in patients with PVGD, but this was not statistically significant.     

Development of an antibody ELISA for potency testing of furunculosis (Aeromonas salmonicida subsp salmonicida) vaccines in Atlantic salmon (Salmo salar L)

The study was conducted in Atlantic salmon to establish the initial and basic scientific documentation for an alternative batch potency test for salmon furuculosis vaccines. We assessed the antibody response development for Aeromonas salmonicida vaccines at different immunisation temperatures (3, 12 and 18 °C), by an enzyme-linked-immunosorbent assay (ELISA) 3, 6, 9 and 12 weeks post vaccination, and the correlation between antibody response and protection in cohabitation challenge experiments performed 6 and 12 weeks post vaccination. Fish immunised with a vaccine containing full antigen dose had a significant increase in antibody response after 252 day degrees and the measured values correlated well with protection after 500 day degrees. Fish vaccinated with a reduced antigen dose showed a significant lower antibody response than fish vaccinated with the full dose vaccine at all samplings, and showed a similar low relative percent survival (RPS) in the challenges. The results from this study indicate that an antibody ELISA can discriminate between vaccines of different antigen content and the method may replace challenge tests in batch potency testing of furunculosis vaccines in Atlantic salmon. An immunisation temperature of 12 °C and sampling after 6-9 weeks, seemed to be the most appropriate time for using antibody responses to confirm batch potency.     

Generation and Efficacy Evaluation of Recombinant Classical Swine Fever Virus E2 Glycoprotein Expressed in Stable Transgenic Mammalian Cell Line

Classical swine fever virus (CSFV) is the causative agent of classical swine fever (CSF), which is a highly contagious swine disease that causes significant economic loses to the pig industry worldwide. The envelope E2 glycoprotein of CSFV is the most important viral antigen in inducing protective immune response against CSF. In this study, we generated a mammalian cell clone (BCSFV-E2) that could stably produce a secreted form of CSFV E2 protein (mE2). The mE2 protein was shown to be N-linked glycosylated and formed a homodimer. The vaccine efficacy of mE2 was evaluated by immunizing pigs. Twenty-five 6-week-old Landrace piglets were randomly divided into five groups. Four groups were intramuscularly immunized with mE2 emulsified in different adjuvants twice at four-week intervals. One group was used as the control group. All mE2-vaccinated pigs developed CSFV-neutralizing antibodies two weeks after the first vaccination with neutralizing antibody titers ranging from 1∶40 to 1∶320. Two weeks after the booster vaccination, the neutralizing antibody titers increased greatly and ranged from 1∶10,240 to 1∶81,920. At 28 weeks after the booster vaccine was administered, the neutralizing antibody titers ranged from 1∶80 to 1∶10240. At 32 weeks after the first vaccination, pigs in all the groups were challenged with a virulent CSFV strain at a dose of 1×10⁵ TCID₅₀. At two weeks after the challenge, all the mE2-immunized pigs survived and exhibited no obvious symptoms of CSF. The neutralizing antibody titer at this time was 20,480. Unvaccinated pigs in the control group exhibited symptoms of CSF 3–4 days after challenge and were euthanized from 7–9 days after challenge when the pigs became moribund. These results indicate that the mE2 is a good candidate for the development of a safe and effective CSFV subunit vaccine.     

Expression of seven herpes simplex virus type 1 glycoproteins (gB, gC, gD, gE, gG, gH, and gI): comparative protection against lethal challenge in mice.

We have constructed recombinant baculoviruses individually expressing seven of the herpes simplex virus type 1 (HSV-1) glycoproteins (gB, gC, gD, gE, gG, gH, and gI). Vaccination of mice with gB, gC, gD, gE, or gI resulted in production of high neutralizing antibody titers to HSV-1 and protection against intraperitoneal and ocular challenge with lethal doses of HSV-1. This protection was statistically significant and similar to the protection provided by vaccination with live nonvirulent HSV-1 (90 to 100% survival). In contrast, vaccination with gH produced low neutralizing antibody titers and no protection against lethal HSV-1 challenge. Vaccination with gG produced no significant neutralizing antibody titer and no protection against ocular challenge. However, gG did provide modest, but statistically significant, protection against lethal intraperitoneal challenge (75% protection). Compared with the other glycoproteins, gG and gH were also inefficient in preventing the establishment of latency. Delayed-type hypersensitivity responses to HSV-1 at day 3 were highest in gG-, gH-, and gE-vaccinated mice, while on day 6 mice vaccinated with gC, gE, and gI had the highest delayed-type hypersensitivity responses. All seven glycoproteins produced lymphocyte proliferation responses, with the highest response being seen with gG. The same five glycoproteins (gB, gC, gD, gE, and gI) that induced the highest neutralization titers and protection against lethal challenge also induced some killer cell activity. The results reported here therefore suggest that in the mouse protection against lethal HSV-1 challenge and the establishment of latency correlate best with high preexisting neutralizing antibody titers, although there may also be a correlation with killer cell activity.     

Rotavirus vaccine administered parenterally induces protective immunity.

We performed experiments to determine whether parenteral immunization with SA11 rotavirus can induce active protective immunity in a rabbit model of rotavirus infection. After one or two intramuscular injections of 1 ml of live or formalin-inactivated SA11 virus, we evaluated the mucosal and serologic immune response and protection from challenge with a high dose of live, virulent rabbit (Ala) rotavirus. Inactivated SA11 virus preparations, evaluated by enzyme-linked immunosorbent assay (ELISA) with a panel of VP4- and VP7-specific neutralizing and nonneutralizing monoclonal antibodies, did not show a loss of epitopes from the inactivation procedure compared with live virus. Administration of two doses of vaccine, one at zero days postvaccination (DPV) and a booster shot at 49 DPV, followed by challenge at 71 DPV with 3.5 x 10(5) PFU of Ala virus resulted in protection from challenge. None of the two-dose virus-vaccinated rabbits shed virus after challenge, while virus shedding was detected in all control rabbits (P = 0.001, Fisher's exact two-tailed test). Differences in total serum immunoglobulin (Ig) antirotavirus ELISA titers (P < 0.05, Wilcoxon's rank sum test) were observed between groups vaccinated with virus in aluminum phosphate or Freund's adjuvant but not between groups vaccinated with live or inactivated virus in either adjuvant. All rabbits given two doses of vaccine had detectable antirotavirus intestinal antibody of the IgG, but not IgA, isotype. After challenge, fourfold or greater increases in intestinal IgG antibody responses were observed in three rabbits, whereas all controls and all but one virus-vaccinated rabbit had an intestinal IgA antibody response. In contrast, vaccination of rabbits with one dose of SA11 followed by challenge at 21 DPV did not protect from challenge; no difference in the mean number of days of virus shedding between any of the vaccinated groups and controls was observed. A serologic, but not a mucosal, antibody response was observed after the one-dose vaccination regimen. Differences in serologic antibody titers were not observed between any of the one-dose virus-vaccinated groups. These data indicate that parenteral vaccination with two, but not one, doses of rotavirus in either Freund's adjuvant or aluminum phosphate can induce active protection from challenge.(ABSTRACT TRUNCATED AT 400 WORDS)     

Immunological evaluation of personalized peptide vaccination in combination with UFT and UZEL for metastatic colorectal carcinoma patients

To investigate the safety and immunological responses of personalized peptide vaccination in combination with oral administration of UFT and UZEL for metastatic colorectal carcinoma (mCRC), fourteen patients were enrolled in the present study. Peptides were determined based on the presence of peptide-specific cytotoxic T lymphocyte precursors and IgG in each patient. A maximum of four peptides were subcutaneously administered weekly with UFT (300 mg/m² day⁻¹) and UZEL (75 mg/day) for 4 weeks, followed by 1 week of rest. This therapy was well-tolerated although there was a grade-3 skin reaction at the vaccination site in one patient. An increase in peptide-specific interferon-γ production or peptide-specific IgG after the tenth vaccination was observed in nine of ten or eight of ten patients tested, respectively. IgG responses were well correlated with overall survival (P = 0.0215). The safety and immunological responsiveness of the present therapy suggest that this combination would be of clinical benefit for mCRC patients, and further trials are merited. T. Hattori and T. Mine equally contributed to this work.     

Clinical reagents of GM-CSF and IFN-α induce the generation of functional chronic myeloid leukemia dendritic cells in vitro

Dendritic cells (DCs) have been successfully induced in vitro from chronic myeloid leukemia (CML) cells, which may provide a promising immunotherapeutic protocol for CML. To facilitate the optimization of DCs-based vaccination protocols, we investigated the efficiency of in vitro generation of DCs from bone marrow mononuclear cells of CML patients by clinical reagents of GM-CSF and IFN-α. Bone marrow mononuclear cells were isolated from eight CML patients and CML-DCs were generated in the presence of different cytokines (Group A: GM-CSF for research and IL-4 for research; Group B: GM-CSF for injection and IFN-α for injection) in RMPI-1640 medium containing 10% human AB serum. After 8 days, the morphologic features of CML-DCs were observed and their immunophenotypes were analyzed by flow cytometry. The activity of CML-DCs was determined by evaluating their ability to stimulate allogeneic mixed lymphocyte reaction (allo-MLR) and anti-leukemic cytotoxic T lymphocytes (CTLs). The culture protocols were successful in generating functional CML-DCs from all the CML patients as evidenced by the significant upregulation of CD80, CD86, CD83 HLA-DR and CD1a compared to pre-cultured (p < 0.05), and increased allogeneic T cell stimulating proliferation capacity (p < 0.05). CML-DCs could stimulate a specific anti-leukemia response. In summary, we demonstrate that the combination of clinical reagents GM-CSF and IFN-α induced the generation of DCs that have the ability to stimulate a specific anti-leukemia CTLs response in vitro, indicating their feasibility for clinical vaccination protocols for CML patients.     

Vaccination response to tetanus toxoid and 23-valent pneumococcal vaccines following administration of a single dose of abatacept: a randomized,open-label,parallel group study in healthy subjects

The effect of abatacept, a selective T-cell co-stimulation modulator, on vaccination has not been previously investigated. In this open-label, single-dose, randomized, parallel-group, controlled study, the effect of a single 750 mg infusion of abatacept on the antibody response to the intramuscular tetanus toxoid vaccine (primarily a memory response to a T-cell-dependent peptide antigen) and the intramuscular 23-valent pneumococcal vaccine (a less T-cell-dependent response to a polysaccharide antigen) was measured in 80 normal healthy volunteers. Subjects were uniformly randomized to receive one of four treatments: Group A (control group), subjects received vaccines on day 1 only; Group B, subjects received vaccines 2 weeks before abatacept; Group C, subjects received vaccines 2 weeks after abatacept; and Group D, subjects received vaccines 8 weeks after abatacept. Anti-tetanus and anti-pneumococcal (Danish serotypes 2, 6B, 8, 9V, 14, 19F and 23F) antibody titers were measured 14 and 28 days after vaccination. While there were no statistically significant differences between the dosing groups, geometric mean titers following tetanus or pneumococcal vaccination were generally lower in subjects who were vaccinated 2 weeks after receiving abatacept, compared with control subjects. A positive response (defined as a twofold increase in antibody titer from baseline) to tetanus vaccination at 28 days was seen, however, in ≥ 60% of subjects across all treatment groups versus 75% of control subjects. Similarly, over 70% of abatacept-treated subjects versus all control subjects (100%) responded to at least three pneumococcal serotypes, and approximately 25–30% of abatacept-treated subjects versus 45% of control subjects responded to at least six serotypes.