Functional and phenotypic characterization of tetanus toxoid-specific human CD4+ T cells following re-immunization

The formation of immunological memory is a hallmark of adaptive immunity and the goal of vaccination. For CD8(+ )T cells, successful generation of memory cells has been linked to IL-7 receptor alpha (IL-7Ralpha) expression, suggesting a role for IL-7 signaling, which in turn is important for preventing T cell apoptosis. We thus investigated the kinetics and changes of IL-7Ralpha and anti-apoptotic protein Bcl-2 expression levels in tetanus toxoid (TT)-specific CD4(+ )T cells at different time points prior and after TT re-immunization of TT-immune individuals. Prior to re-immunization, most TT-specific CD4(+ )T cells were high IL-2 producers, CD45RA(-)CCR7(+), IL-7Ralpha(high)Bcl-2(high) cells, resembling typical long-lived central memory cells. Already 5 days, and more importantly at the peak of the response, after TT re-immunization, a substantial fraction of these cells secreted also IFN-gamma, down-regulated CCR7, IL-7Ralpha and Bcl-2 and became Ki67 positive, resembling effector memory cells. In contrast, TT-specific CD4(+ )T cells found 60 days or later after re-immunization were again as baseline. Interestingly, a significant fraction of IL-7Ralpha(high)Bcl-2(high) TT-specific CD4(+ )T cells, i.e. the proposed memory cell precursors, remained stable at any time point upon re-immunization. Together, these results suggest that IL-7Ralpha expression levels might be a useful marker for identifying long-lived Ag-specific CD4(+ )T cells in memory T cells.

Tetanus immunization status among women of childbearing age in Turkey

In order to assess the effect of the neonatal tetanus elimination program in Turkey, tetanus antibody prevalence among women of childbearing age from three selected provinces was evaluated in relation to vaccination doses of the single-type tetanus vaccine. A combined method of in-house enzyme-linked immunosorbent assay and particle agglutination test was used to determine tetanus antibody titers. Among 205 women aged 20-39 years, the tetanus antibody level was higher in women with 1-3 children than those without children. The geometric mean of the log antibody titer was increased proportionally with a slope of 0.405 +/- 0.174 per dose between 0 and 3 doses (P > 0.05). However, the proportion of 20-39-year-old women with the protective antibody in the provinces ranged from 54.8 to 86.6%. Diyarbakir had the lowest immunity with a larger number of children in the household, and a lower educational level. The results of our serological study demonstrated that the neonatal tetanus elimination program in Turkey is effectively promoting immunity against tetanus in pregnant women. However, the study also revealed that the tetanus immunity among women of childbearing age was still insufficient. Intensive implementation of the supplemental immunization activities and encouraging vaccinations through neonatal care services will improve the situation.

Haemophilus influenzae meningitis 5 years after introduction of the Haemophilus influenzae type b conjugate vaccine in Brazil

The long-term impact of Haemophilus influenzae type b (Hib) conjugate vaccine, introduced throughout Latin America in the late 1990s, has not been evaluated. Active surveillance for H. influenzae meningitis was performed from August 9, 1996 to August 8, 2004 in Metropolitan Salvador, Brazil. Five years after the introduction of Hib conjugate vaccine, Hib meningitis incidence decreased from 2.39 to 0.06 cases per 100,000 population (98%) overall, and from 60.9 to 3.1 cases per 100,000 population (95%) in children <1 year of age. A transient serotype replacement phenomenon was observed associated with a small increase of meningitis due to two H. influenzae type a clonal groups. These findings indicate that Hib immunization campaign has led to the virtual elimination of Hib disease in this region.

Enhanced surveillance for adverse events following immunization: Two years of dTap catch-up among high school students in Yukon, Canada (2004, 2005)

BACKGROUND

To address the increasing age of pertussis cases, Yukon replaced the Grade 9 tetanus/diphtheria/inactivated polio booster with diphtheria/tetanus/acellular pertussis (dTap) and implemented a dTap catch-up program for Grade 12 students. The program began in June 2004, making Yukon one of the first Canadian jurisdictions to introduce dTap within five years of a tetanus booster. We implemented enhanced surveillance to monitor adverse events following immunization (AEFI) to determine whether students receiving dTap > or =3 to <5 years after their last tetanus booster were at increased risk of severe AEFI.

METHODS

Students completed a self-administered AEFI questionnaire one week post-dTap vaccination. Public health professionals contacted students reporting severe AEFI. Health care providers were requested to report AEFI. Symptom rate, severity and duration were compared between students receiving dTap > or =3 to <5 years after their last tetanus booster and those receiving it >5 years later.

RESULTS

The > or =3 to <5 years group was more likely than the > or =5 years group to report pain at the injection site (70.6% vs. 61.5%, p=0.038) and less likely to report injection site redness (10.0% vs. 17.3%, p=0.022), injection site swelling (8.9% vs. 16.4%, p=0.013), decreased energy (10.0% vs. 17.1%, p=0.023), body aches (2.2% vs. 7.2%, p=0.014) and sore joints (3.3% vs. 10.1%, p=0.004). Severe AEFI did not differ between the groups (3.3% vs. 5.6%, p=0.232). Health care professionals reported no AEFI.

CONCLUSIONS

Results suggest no increased risk of severe AEFI among students receiving dTap > or =3 to <5 years after their last tetanus booster.

Revaccination of Children after Completion of Standard Chemotherapy for Acute Leukemia

BACKGROUND

After the treatment of patients with acute leukemia, there is a decrease in vaccine-specific antibody and an increased susceptibility to certain vaccine-preventable diseases. A simple revaccination schedule is warranted.

METHOD

Fifty-nine children (age, 1-18 years) who had completed standard chemotherapy in accordance with Medical Research Council of United Kingdom protocols were recruited. All children received a single dose of Haemophilus influenzae type b (Hib), tetanus, diphtheria, acellular pertussis, meningococcus C, polio, measles, mumps, and rubella vaccines > or = 6 months after completion of treatment. Antibody concentrations were measured before vaccination and 2-4 weeks and 12 months after vaccination.

RESULTS

Prevaccination antibody levels were protective for all patients for tetanus (geometric mean concentration [GMC], 0.13 IU/mL; 95% CI, 0.1-0.17 IU/mL), for 87% for Hib (GMC, 0.5 microg/mL; 95% CI, 0.37-0.74 microg/mL), for 71% for measles (GMC, 301 mIU/mL; 95% CI, 163-557 mIU/mL), for 12% for meningococcus C (geometric mean titer [GMT], 1:2.9; 95% CI, 1:2.2 to 1:3.9), and for 11% for all 3 poliovirus serotypes. Revaccination resulted in a significant increase in levels of antibody to each vaccine antigen, with 100% of patients achieving optimal antitetanus antibody concentrations (defined as > 0.1 IU/mL; 1.5 IU/mL; 95% CI, 1.1-2.1 IU/mL), 93% achieving optimal antibody concentrations to Hib (defined as > 1.0 microg/mL; 6.5 microg/mL; 95% CI, 5.1-8.2 microg/mL), 94% achieving optimal antibody concentrations to measles (defined as > or = 120 mIU/mL; 2720 mIU/mL; 95% CI, 1423-5198 mIU/mL), 96% achieving optimal antibody concentrations to meningococcus C (defined as > or = 1:8; 1:1000; 95% CI, 1:483-1:2064), and 85% achieving optimal antibody concentrations to all the 3 poliovirus serotypes (defined as > or = 1:8). For the majority of subjects, protection persisted for at least 12 months after vaccination.

CONCLUSION

Revaccination of children after standard chemotherapy is important, and protection can be achieved in the majority of these children using a simple schedule of 1 vaccine dose at 6 months after completion of leukemia therapy.

Simultaneous vaccination in Japanese travelers

BACKGROUND

Simultaneous vaccination is not common in Japan because there is little information available on its effects. Some people are quite concerned about the possibility of adverse reactions due to simultaneous vaccination. The objective of this study was to evaluate whether the frequency and severity of adverse effects are increased by simultaneous vaccination in comparison to single vaccination.

METHOD

A retrospective observational study was conducted in 399 asymptomatic travelers who visited the travel clinic during the period January-July 2005. One hundred forty-two participants were given a single vaccination, 257 participants were given simultaneous vaccination. Travel-specific vaccinations were for hepatitis A, hepatitis B, tetanus, rabies and Japanese encephalitis, and routine vaccines were for diphtheria+tetanus, measles, mumps and oral polio vaccine. To evaluate adverse effects, travelers were asked to complete a prepared questionnaire after vaccination.

RESULTS

Adverse effects were reported by 26.3% of travelers, with 21.8% reporting local reactions and 4.5% reporting systemic reactions. The simultaneous vaccination group reported significantly more frequent adverse effects than those reported by the single vaccination group. Particularly, tetanus vaccination was shown to significantly raise the risk of adverse effects (P<0.001). However, no serious adverse effects were reported.

CONCLUSIONS

Simultaneous vaccination was feasible for Japanese travelers because most problems were generally minor and related to local reactions at the sites of injections. Provision of a simultaneous vaccination schedule should motivate more Japanese travelers to obtain immunizations and thereby reduce the risk of vaccine-preventable diseases.

A case of childhood tetanus in Cyprus in 2003: a rarely seen disease

We describe a case of childhood tetanus in a child who had received no vaccination for the disease, and who developed tetanus following a leg injury.

[Generalized tetanus in a teenager]

Tetanus has become an exceptional disease in industrialized countries since vaccination.

CASE REPORT

We report a case of generalized tetanus in a young teenager, with a healthy outcome, but requiring long intensive care support.

CONCLUSION

Tetanus mortality has decreased, but its morbidity is still severe. The only way to prevent it is vaccination. Almost all pediatric cases concern patients living in families refusing vaccination, because of philosophic or religious beliefs.

Revaccination with measles, tetanus, poliovirus, Haemophilus influenzae type B, meningococcus C, and pneumococcus vaccines in children after hematopoietic stem cell transplantation

BACKGROUND

There is a decrease in antibody levels after hematopoietic stem cell transplant (HSCT), and such patients may be at increased risk of acquiring vaccine-preventable infection. A simple and validated revaccination schedule is required. The aim of this study was to evaluate the immunogenicity of a revaccination schedule for pediatric HSCT recipients.

METHODS

Thirty-eight children (age, 1-18 years) who had undergone autologous or allogeneic HSCT for malignant diseases were recruited. All children received vaccinations in accordance with a predefined schedule. Antibody concentrations were measured before and 2-4 weeks after vaccination against tetanus; Haemophilus influenzae type b (Hib); meningococcus C; measles; poliovirus serotypes 1, 2, and 3; and 9 pneumococcus serotypes.

RESULTS

Before vaccination, protective antibody levels were found for tetanus in 95% of patients (geometric mean concentration [GMC], 0.07 IU/mL; 95% CI, 0.05-0.1 IU/mL), for Hib in 63% (GMC, 0.34 microg/mL; 95% CI, 0.21-0.57 microg/mL), for measles in 60% (GMC, 102 mIU/mL; 95% CI, 41-253 mIU/mL), for meningococcus C in 11% (geometric mean titer [GMT], 1:4; 95% CI, 1:2-1:8.4), for all 3 poliovirus serotypes in 29%, and for all 9 pneumococcal serotypes in 0%. Vaccination resulted in a significant increase (P < or = .05) in antibody levels to each vaccine antigen studied, with 100% of patients achieving protection against tetanus (GMC, 2.2 IU/mL; 95% CI, 1.8-2.7 IU/mL), 100% achieving protection against Hib (GMC, 8.4 microg/mL; 95% CI, 7.6-9.3 microg/mL), 100% achieving protection against measles (GMC, 2435 mIU/mL; 95% CI, 1724-3439 mIU/mL), 100% achieving protection against meningococcus C (GMT, 1:5706; 95% CI, 1:3510-1:9272), 92% achieving protection against the 3 poliovirus serotypes, and > or = 80% achieving protection against each of the heptavalent pneumococcal conjugate vaccine-associated serotypes. No factors relevant to age, underlying disease, or treatment type were found to significantly influence responses.

CONCLUSION

Revaccination of pediatric HSCT recipients in accordance with this revaccination schedule provides a high level of protection against these vaccine-preventable diseases.

Adjuvant properties of bacterial product cantastim

Aluminum compounds have been used as adjuvants in practical vaccination for more than 60 years to induce an early, an efficient and a long lasting protective immunity. Nowadays they are the most widely used adjuvants in both veterinary and human vaccines. Unfortunately these adjuvants do not only cause undesirable side effects, but often induce T-helper type 2 (Th2)-biased responses. In this study we investigated the ability of the bacterial product CANTASTIM (CS) to augment the immune responses to a model antigen, tetanus toxoid (TT). Immunization of mice with TT+CS elicited higher anti-TT IgG antibody levels as compared to mice that received TT alone. Moreover, treatment with TT+CS resulted in a lower IgG1/IgG2a ratio and a stronger in vitro IFN-gamma synthesis by splenocytes and T cells cocultured with macrophages. These data suggest that CS can be used to enhance the magnitude of the immune response and to skew it towards the Th1 type.

[Tetanus in 2005]

In last decade gradual decrease in numbers of reported cases of tetanus was observed. In 2005, 15 cases of tetanus (10 women and 5 men) were reported in Poland. All those cases were among people of age 50 or more. In 2005 6 deaths were recorded All cases were unvaccinated or vaccination status was unknown. Only in 2 cases post exposure anatoxin was applied. The data show effectiveness of vaccination program in younger age groups, but they also show need for promotion of post exposure prophylaxis, especially among older people both in rural and in urban areas. No case of neonatal tetanus was noted in Poland since 1984.

Relationships among physico-chemical and biological tests for a synthetic Hib–TT conjugate vaccine

The relationships among physico-chemical and biological tests were evaluated in this study for Cuban Hib vaccine, a tetanus toxoid conjugated with a polysaccharide obtained from chemical synthesis, in order to estimate the biological significance of the relevant physico-chemical assays for lot released. In order to get samples with theoretical different potencies, Hib-TT samples were stored at -20, 4, 25, 37 and 70 degrees C for 5 weeks and after they were evaluated by HPLC and Orcinol methods and for immunogenicity and bactericidal activity. We found strong relationships between HPLC and free PRP level (r2=0.9571), anti-PRP antibodies and bactericidal activity (r2=0.9649) and free PRP content and anti-PRP antibodies titres (r2=0.7671). A lower correlation was found for HPLC and anti-PRP titres (r2=0.5996). We demonstrate that it is possible to monitor this new product combining physico-chemical and biological tests in order to contribute to its characterisation.

Effect of a mixture of micronutrients, but not of bovine colostrum concentrate, on immune function parameters in healthy volunteers: a randomized placebo-controlled study

Background

Supplementation of nutritional deficiencies helps to improve immune function and resistance to infections in malnourished subjects. However, the suggested benefits of dietary supplementation for immune function in healthy well nourished subjects is less clear. Among the food constituents frequently associated with beneficial effects on immune function are micronutrients such as vitamin C, vitamin E, β-carotene and zinc, and colostrum. This study was designed to investigate the effects these ingredients on immune function markers in healthy volunteers.

Methods

In a double-blind, randomized, parallel, 2*2, placebo-controlled intervention study one hundred thirty-eight healthy volunteers aged 40–80 y (average 57 ± 10 y) received one of the following treatments: (1) bovine colostrum concentrate 1.2 g/d (equivalent to ~500 mg/d immunoglobulins), (2) micronutrient mix of 288 mg vitamin E, 375 mg vitamin C, 12 mg β-carotene and 15 mg zinc/day, (3) combination of colostrum and micronutrient mix, or (4) placebo. Several immune function parameters were assessed after 6 and 10 weeks. Data were analyzed by analysis of variance. Groups were combined to test micronutrient treatment versus no micronutrient treatment, and colostrum treatment versus no colostrum treatment.

Results

Overall, consumption of the micronutrient mix significantly enhanced delayed-type hypersensitivity (DTH) responses (p < 0.05). Adjusted covariance analysis showed a positive association between DTH and age. Separate analysis of younger and older age groups indicated that it was the older population that benefited from micronutrient consumption. The other immune function parameters including responses to systemic tetanus and oral typhoid vaccination, phagocytosis, oxidative burst, lymphocyte proliferation and lymphocyte subset distribution were neither affected by the consumption of micronutrients nor by the consumption of bovine colostrum concentrate.

Conclusion

Consumption of bovine colostrum had no effect on any of the immune parameters assessed. The micronutrient mix enhanced cellular immunity as measured by DTH, with an increased effect by incremental age, but did not affect any of the other immune parameters measured. Although correlations between decreased DTH and enhanced risk of certain infection have been reported, it remains unclear whether and enhanced DTH response actually improves immune defense. The present data suggests that improvement of immune parameters in a population with a generally good immune and nutritional status is limited and that improvement of immune function in this population may be difficult.

Cat and dog bites. What to do? Guidelines for the treatment of cat and dog bites in humans

INTRODUCTION

Domestic animal bites are quite common, but mostly cause minor lesions, for which no medical help is sought. The objective of this study is to define the complications resulting from cat and dog bites that lead to hospital admission. This analysis led to updated guidelines for the treatment of dog and cat bites in humans.

PATIENTS AND METHODS

The emergency department (ED) data of our hospital for the year 2004 were retrospectively analysed, seeking patients that presented with bite wounds from either cat or dog. The patient files were reviewed.

RESULTS

34 patients, bitten by cats or dogs, presented to our ED in 2004. 73.5% of them (n = 25) consulted within 24 hours after the bite. In 11 of these patients (44.0%), primary closure of the wound was performed after thorough rinsing and evaluation of the dead space. All these patients were given prophylactic antibiotics. In none of these did the wounds need to be reopened afterwards. Nine patients (26.5%) did not present to the ED until after the day they were bitten. In all these patients, the bite wounds were located on the hand (n = 6) or forearm (n = 3). They all consulted because of complications. The main symptoms were limited and there was painful mobilisation of fingers and wrist, and swelling and redness in the area of the bite wound. Their wounds were thoroughly explored and in 6 of these nine late-presenting patients, a tendon lesion or a purulent flexor tenosynovitis was diagnosed. These six patients needed admission for further management. The mean admission duration was 6 days (range 4 to 10 days). None of the admitted patients showed any signs of limited mobility or disability during follow-up after discharge.

CONCLUSION

While cat and dog bites often cause minor lesions that can be treated by thorough wound care if presented early, the importance of possible late complications should not be overlooked. Patients that present with the symptoms of tissue infection due to a cat or dog bite should be examined adequately and may need admission. Due to aggressive treatment, we had no serious or disabling complications in our population after discharge.

Analysis of patients treated during four Disaster Medical Assistance Team deployments

To aid disaster planning, a retrospective review of patients seen by New Mexico 1 Disaster Medical Assistance Team (NM-1 DMAT) after four disasters was conducted. Data analyzed included age, gender, past medical history, chief complaint, diagnosis, diagnostic testing, treatment, triage category, disposition, and time to presentation after the disaster. Data were analyzed for differences between patients presenting early vs. late after a disaster and to test if availability of diagnostic testing changed patient disposition. The results showed that the majority of patients presented with upper respiratory tract infection symptoms, wounds, and musculoskeletal pain. The needs of patients were similar whether they presented early or late. The same proportion of patients was transferred to hospitals when diagnostic testing was available vs. not available, despite a higher level of acuity when diagnostic testing was available. In conclusion, DMATs should be prepared to see high volumes of low acuity patients. Patient needs do not change with time. Diagnostic testing may be useful.

Acellular pertussis vaccine boosters combined with diphtheria and tetanus toxoid boosters for adolescents: safety and immunogenicity assessment when preceded by different 5-dose DTaP/DTwP schedules

A sixth dose of tetanus, diphtheria, acellular pertussis (Tdap) vaccine in adolescents might produce a differing reactogenicity and/or immunogenicity response depending on the composition of the 5 prior doses of DTaP or DT-whole cell pertussis (DTwP) vaccine. Reactions and immune responses following receipt of the Sanofi Pasteur (Adacel) and GlaxoSmithKline (Boostrix) Tdap vaccines were assessed in 229 adolescents. No differences were observed for reactions to either Tdap vaccine regardless of the prior DTaP/DTwP vaccination history. Seroprotective levels and antibody concentrations were comparable regardless of prior DTaP/DTwP vaccine history. A sixth sequential dose of Tdap after 5 doses of DTaP appears safe and immunogenic.

Reduction of the ganglioside binding activity of the tetanus toxin HC fragment destroys immunogenicity: implications for development of novel tetanus vaccines

In this study, the immunogenicities of the nontoxic H(C) fragment of tetanus toxin and derivatives lacking ganglioside binding activity were compared with that of tetanus toxoid after subcutaneous immunization of mice. Wild-type H(C) (H(C)WT) protein and tetanus toxoid both elicited strong antibody responses against toxoid and H(C) antigens and provided complete protection against toxin challenge. Mutants of H(C) containing deletions essential for ganglioside binding elicited lower responses than H(C)WT. H(C)M115, containing two amino acid substitutions within the ganglioside binding site, provided reduced protection against tetanus toxin challenge compared with H(C)WT, consistent with lower anti-H(C) and anti-toxoid antibody titers. Circular-dichroism spectroscopy and intrinsic fluorescence spectroscopy showed minimal structural perturbation in H(C)M115. We conclude that the presence of the ganglioside binding site within H(C) may be essential for induction of a fully protective anti-tetanus response comparable to that induced by tetanus toxoid by subcutaneous injection.

Enhanced immunisation and expression strategies using bacterial spores as heat-stable vaccine delivery vehicles

Spores of the gram positive bacterium Bacillus subtilis have been used as oral vaccine vehicles and have been shown to confer protection against tetanus in mice. In this work, we have used tetanus as a model with which to examine different antigen presentation strategies as well as dosing regimes using the TTFC antigen of Clostridium tetani. We show that display of the antigen on the spore surface produces a more pronounced, but less rapid, response than when the antigen is expressed in the germinating spore; though this response has a clear Th1 bias. When using the nasal dosing route ten times less spores were needed to produce the same level of protective antibodies using surface display of TTFC. Expression of the antigen within the germinating spore by contrast enables as little as three oral doses on consecutive days to generate protection with a noticeable Th2 bias. We have also shown that TTFC can be expressed using two routes, using display on the spore surface as well as in the germinating spore. This dual route produced the best responses in terms of magnitude and speed of neutralising response as well as a clear Th1 bias indicating the involvement of cellular as well as humoral responses.

Additional conjugation methods and immunogenicity of Bacillus anthracis poly-gamma-D-glutamic acid-protein conjugates

The capsule of Bacillus anthracis, composed of poly-gamma-d-glutamic acid (gammaDPGA), is an essential virulence factor of B. anthracis. The capsule inhibits innate host defense through its antiphagocytic action. gammaDPGA is a poor immunogen, but when covalently bound to a carrier protein, it elicits serum antibodies. To identify the optimal construct for clinical use, synthetic gammaDPGAs of different lengths were bound to carrier proteins at different densities. The advantages of the synthetic over the natural polypeptide are the homogeneous chain length and end groups, allowing conjugates to be accurately characterized and standardized and their chemical compositions to be related to their immunogenicities. In the present study, we evaluated, in addition to methods reported by us, hydrazone, oxime, and thioether linkages between gammaDPGA and several proteins, including bovine serum albumin, recombinant Pseudomonas aeruginosa exotoxin A, recombinant B. anthracis protective antigen (rPA), and tetanus toxoid (TT). The effects of the dosage and formulation on the immunogenicities of the conjugates were evaluated in mice. All conjugates were immunogenic. The optimal gammaDPGA chain length of 10 to 15 amino acids and the density, an average of 15 mol gammaDPGA per mol of protein, were confirmed. The thioether bond was the optimal linkage type, and TT and rPA were the best carriers. The optimal dosage was 1.2 to 2.5 microg of gammaDPGA per mouse, and adsorption of the conjugates onto aluminum hydroxide significantly increased the antibody response to the protein with a lesser effect on anti-gammaDPGA levels.

Dose-response to type V group B streptococcal polysaccharide-tetanus toxoid conjugate vaccine in healthy adults

A phase 1, dose-escalating trial was conducted in healthy adults to evaluate immunogenicity and reactogenicity of a type V group B streptococcal (GBS) capsular polysaccharide (CPS)-tetanus toxoid (TT) conjugate vaccine. Participants received one dose of unconjugated V CPS (37 microg), V-TT (2.4 microg CPS/1.1 microg TT), V-TT (9.6 microg CPS/4.3 microg TT) or V-TT (38.5 microg CPS/17.0 microg TT). Each vaccine and all doses of V-TT were well-tolerated. V CPS-specific antibodies reached a peak 4-8 weeks after immunization and were significantly higher through 52 weeks post-immunization in recipients of V-TT at each dose than in uncoupled CPS vaccinees. V-TT vaccine-induced antibodies promoted opsonophagocytic killing of type V GBS and avidity maturation of V CPS-specific IgG.

Tetanus vaccination and risk of multiple sclerosis: A systematic review

OBJECTIVE

To conduct a systematic review on the association between tetanus vaccination and the risk of multiple sclerosis (MS).

METHODS

The authors searched the databases Medline, LILACS, EMBASE, and Science Citation Index including the period 1966 to September 1, 2005. Eligible studies had to meet the following inclusion criteria: presentation of original data, case-control or cohort design, physician-confirmed diagnosis of MS as the outcome of interest, attempt to ascertain vaccinations in a period before the diagnosis, and report of an association measure between tetanus vaccination and incidence of MS, and its 95% CI or enough information to compute it. Study specific log ORs were weighted by the inverse of their variances to obtain a pooled estimate and its 95% CI.

RESULTS

The OR of MS associated with history of tetanus vaccination was 0.67 (95% CI: 0.55 to 0.81). There was little indication of heterogeneity of results across studies.

CONCLUSION

Tetanus vaccination is associated with a lower risk of multiple sclerosis.

Single dose vaccine based on biodegradable polyanhydride microspheres can modulate immune response mechanism

This study focuses on the development of single dose vaccines based on biodegradable polyanhydride microspheres that have the unique capability to modulate the immune response mechanism. The polymer system employed consists of copolymers of 1,6-bis(p-carboxyphenoxy)hexane and sebacic acid. Two copolymer formulations that have been shown to provide extended release kinetics and protein stability were investigated. Using tetanus toxoid (TT) as a model antigen, in vivo studies in C3H/HeOuJ mice demonstrated that the encapsulation procedure preserves the immunogenicity of the TT. The polymer itself exhibited an adjuvant effect, enhancing the immune response to a small dose of TT. The microspheres provided a prolonged exposure to TT sufficient to induce both a primary and a secondary immune response (i.e., high antibody titers) with high-avidity antibody production, without requiring an additional administration. Antigen-specific proliferation 28 weeks after a single immunization indicated that immunization with the polyanhydride microspheres generated long-lived memory cells and plasma cells (antibody-secreting B cells) that generally do not occur without maturation signals from T helper cells. Furthermore, by altering the vaccine formulation, the overall strength of the T helper type 2 immune response was selectively diminished, resulting in a balanced immune response, without reducing the overall titer. This result is striking, considering free TT induces a T helper type 2 immune response, and has important implications for developing vaccines to intracellular pathogens. The ability to selectively tune the immune response without the administration of additional cytokines or noxious adjuvants is a unique feature of this delivery vehicle that may make it an excellent candidate for vaccine development.

Vaccination of melanoma patients using dendritic cells loaded with an allogeneic tumor cell lysate

The aim of the present phase I/II study was to evaluate the safety, immune responses and clinical activity of a vaccine based on autologous dendritic cells (DC) loaded with an allogeneic tumor cell lysate in advanced melanoma patients. DC derived from monocytes were generated in serum-free medium containing GM-CSF and IL-13 according to Good Manufacturing Practices. Fifteen patients with metastatic melanoma (stage III or IV) received four subcutaneous, intradermal, and intranodal vaccinations of both DC loaded with tumor cell lysate and DC loaded with hepatitis B surface protein (HBs) and/or tetanus toxoid (TT). No grade 3 or 4 adverse events related to the vaccination were observed. Enhanced immunity to the allogeneic tumor cell lysate and to TAA-derived peptides were documented, as well as immune responses to HBs/TT antigens. Four out of nine patients who received the full treatment survived for more than 20 months. Two patients showed signs of clinical response and received 3 additional doses of vaccine: one patient showed regression of in-transit metastases leading to complete remission. Eighteen months later, the patient was still free of disease. The second patient experienced stabilization of lung metastases for approximately 10 months. Overall, our results show that vaccination with DC loaded with an allogeneic melanoma cell lysate was feasible in large-scale and well-tolerated in this group of advanced melanoma patients. Immune responses to tumor-related antigens documented in some treated patients support further investigations to optimize the vaccine formulation.

Development of novel fusogenic vesosomes for transcutaneous immunization

Transcutaneous immunization (TCI) is a novel vaccination strategy based on the application of antigen together with an adjuvant onto hydrated bare skin. This simple and non-invasive immunization procedure elicits systemic and cell mediated immune responses and therefore, it provides a viable and cost-effective strategy for disease prevention. In the present study, novel fusogenic vesicular carrier constructs, i.e. vesosomes were developed and evaluated for topical delivery of vaccines using tetanus toxoid (TTx) as a model antigen. Prepared vesosomes were characterized for size, shape, entrapment efficiency and zeta potential. The prepared novel systems were examined for in process antigen stability and long-term storage stability studies. In vitro skin permeation and fluorescence microscopy study were also preformed for prepared novel vesicular systems for the evaluation of skin penetration efficiency. The immune stimulating activity of these vesicles was studied by measuring the serum anti-tetanus toxoid IgG titer and isotype ratio IgG2a/IgG1 following topical immunization in three different protocols and results were compared with the alum adsorbed tetanus toxoid given intramuscularly and topically administered plain tetanus toxoid solution, plain liposomes and cationic fusogenic liposomes. Serum IgG titers after three consecutive topical administrations were significantly better (*P < 0.05) than single administration of TTx antigen with vesosomal systems, suggesting an effective stimulation of serum immune response. Furthermore, notable serum anti-TTx antibody titers also occurred in animals primed with alum adsorbed TTx and subsequently boosted with topical administration of novel vesosomal systems. In each immunization studies, the vesosomal systems could elicit combined Th1 and Th2 immune responses following topical administration. These results suggest that the investigated vesosomal systems can be effective as topical delivery of vaccines.

[Last minute vaccinations]

Various vaccinations applied at short notice before a person leaves for a foreign country can still provide full protection from certain diseases. This applies in particular to the generally recommended vaccinations against diphtheria and tetanus; additionally, a booster shot against poliomyelitis also provides complete protection within a few days. Immunization against hepatitis A, yellow fever (in particular Africa), typhoid fever and, where appropriate, meningococci is available at the latest ten days before starting a journey. However, no last-minute protection is possible for hepatitis B, rabies, Japanese encephalitis or TBE.

Nasal immunization studies using liposomes loaded with tetanus toxoid and CpG-ODN

To increase the systemic and mucosal immune responses against the nasally administered tetanus toxoid, liposomes as a drug delivery system and CpG-ODN as an adjuvant were evaluated. Rabbits were nasally immunized with entrapped tetanus toxoid (TT) and CpG-ODN in neutral liposomes and systemic and mucosal immune responses were determined. Liposomes containing TT and CpG-ODN were prepared by dehydration-rehydration method. The volume mean diameter of liposomes was 2.3+/-0.6 microm. Encapsulation efficiency of TT and CpG-ODN was determined as 54.0+/-8.8 and 60.1+/-7.4, respectively. The leakage of the encapsulated TT from liposomes reached 7.38% after 3 months. Encapsulated TT kept its intact structure, and its immunoreactivity was also completely preserved, as shown by SDS-PAGE and ELISA methods. The highest serum IgG and antitoxin titers were observed in groups immunized with solution formulations (P < 0.001). However the highest mucosal sIgA titers were achieved by liposomes encapsulated with TT. CpG-ODN as an adjuvant was able to increase the serum IgG and antitoxin titers when co-administered with TT solution (P < 0.05) or co-encapsulated with TT in liposomes (P < 0.01), but failed to increase the sIgA titers in nasal lavages. No hemolysis occurred on incubation of liposomes and human RBCs. Also after nasal administration of plain liposomes to human volunteers, no local irritation was seen. Intranasal administration of liposomes encapsulated with vaccines showed to be an effective way for inducing the mucosal immune responses.

Predominant influence of environmental determinants on the persistence and avidity maturation of antibody responses to vaccines in infants

BACKGROUND

Immune responses are complex traits influenced by genetic and environmental factors. We previously reported that genetic factors control early antibody responses to vaccines in Gambian infants. For the present study, we evaluated the determinants of the memory phase of immunoglobulin G (IgG) responses.

METHODS

Antibody responses to tetanus toxoid (TT), measles vaccines, and environmental antigens (total IgG levels) were measured in 210 Gambian twin pairs recruited at birth. Intrapair correlations for monozygous and dizygous pairs were compared to estimate the environmental and genetic components of variations in response.

RESULTS

In contrast to antibody responses measured in infants at age 5 months, 1 month after immunization, no significant contribution of genetic factors to anti-TT antibody and total IgG levels was detected at age 12 months. Genetic factors controlled measles antibody responses in 12-month-old infants, which indicates that the increasing influence of environmental determinants on anti-TT responses was not related to the older age of the children but, rather, to the time elapsed since immunization. Environmental factors also predominantly controlled affinity maturation and the production of high-avidity antibodies to TT.

CONCLUSIONS

Genetic determinants control the early phase of the vaccine antibody response in Gambian infants, whereas environmental determinants predominantly influence antibody persistence and avidity maturation.

Induction of systemic and mucosal immune responses by intranasal administration of alginate microspheres encapsulated with tetanus toxoid and CpG-ODN

In the induction of systemic and mucosal immunity, particulate antigens are more effective than soluble antigens; possibly because they are more efficiently endocytosed by mucosal-associated lymphoid tissue (MALT) M cells. In this study, we determined the systemic and mucosal immune responses in rabbits following intranasal immunization with encapsulated tetanus toxoid (TT) and CpG-ODN in alginate microspheres. The microspheres were less than 4 microm in diameter. Encapsulation efficiency of TT and CpG-ODN was determined as 47.7+/-6.6 and 34.2+/-7.4, respectively. Release of TT and CpG-ODN in a simulated model with nasal cavity was 14.2+/-3.06 and 36.7+/-2.4% after 4 h. Encapsulated TT preserved its intact structure, but its immunoreactivity was decreased to about 91+/-5%. The highest serum IgG and antitoxin, and nasal lavage IgA titers were observed in groups immunized with microsphere formulations. CpG-ODN as an adjuvant could increase the serum IgG and antitoxin titers when co-administered with TT solution, but its co-encapsulation with TT in alginate microspheres failed to potentiate the systemic immune response while induced high IgA titers in nasal lavages. No hemolysis was occurred on incubation of alginate microspheres and human RBCs. Also after nasal administration of plain microspheres to human volunteers, no local irritation was observed. Intranasal administration of microspheres encapsulated with vaccines showed to be an effective way for inducing a variety of immune responses and that a strong systemic IgG and mucosal IgA responses can be induced in rabbits with intranasal administration of alginate microspheres encapsulated with TT.

Evaluation of two GnRH-I based vaccine formulations on the testes function of entire Suffolk cross ram lambs

A modified GnRH peptide (CHWSYGLRPG-NH(2)) was conjugated to tetanus toxoid (TT) or diphtheria toxoid (DT) and formulated with Quil A saponin or a sustained release injectible PLGA (poly(lactide-co-glycolide)/triacetin). For the Quil A formulations, two administrations of TT conjugate at 3-weekly intervals were followed by two booster injections with the DT conjugate in entire ram lambs. With the PLGA formulations, only two injections were administered; the first containing TT and the second DT at 6-weekly intervals. Evaluation was carried out by comparing the specific antibody levels produced in relationship to hormone profiles and testicular changes. The Quil A formulation was considered the most effective, as it caused significant reduction in testosterone and follicle stimulating hormone levels, resulting in marked suppression of spermatogenesis.

Extensive swelling reaction associated with diphtheria and tetanus toxoids and acellular pertussis vaccine

Although extensive swelling reactions in the injected limb after the administration of diphtheria-tetanus toxoid-acellular pertussis vaccine have been reported previously, to our knowledge, computerized tomography images of this entity have not been published. A 4-year-old boy with extensive swelling after vaccination with diphtheria-tetanus toxoid-acellular pertussis vaccine is presented.

Haemophilus influenzae type b immunization in infants in the United Kingdom: effects of diphtheria/tetanus/acellular pertussis/Hib combination vaccine, significant prematurity, and a fourth dose

OBJECTIVE

To measure anti-polyribosylribitolphosphate (PRP) antibody and anti-tetanus toxoid (TT) antibody responses in UK infants to explore the effects of (1) immunization with an acellular diphtheria/tetanus/pertussis/Haemophilus influenzae type b (DTPHib) combination vaccine, (2) significant preterm delivery, and (3) a fourth dose of conjugated Hib vaccine (PRP-T) in those with a low anti-PRP antibody (<1.0 microg/mL) after primary immunization.

METHODS

A prospective study was conducted in 4 tertiary neonatal units at a time when 2 types of DTPHib vaccines were used interchangeably in the United Kingdom for primary immunization: acellular (DTPaHib) and whole cell. Timing and type of all vaccine doses were as per standard UK practice. Blood was taken before and after immunization. A total of 166 preterm and 45 term infants completed the study; 97 (15 term) infants who had anti-PRP antibody <1.0 microg/mL were offered a fourth dose of PRP-T; 61 (55 preterm) then had repeat antibody measurements. Anti-PRP and anti-TT antibody after primary immunization relative to gestation and number of whole cell vaccine doses received was measured, as well as anti-PRP antibody after a fourth dose of PRP-T.

RESULTS

A total of 49% of preterm and 33% of term infants had anti-PRP antibody <1.0 microg/mL after full primary immunization. Receipt of 1 or more acellular vaccine doses was associated with lower anti-PRP antibody, a dose response effect being observed. Preterm infants were less likely to have anti-PRP antibody >1.0 microg/mL compared with term infants. A total of 93% of infants who were given a fourth dose had anti-PRP antibody >1.0 microg/mL. Anti-TT antibody responses were satisfactory for all infants but also reduced by each DTPaHib dose received.

CONCLUSION

Infants who receive DTPaHib, are significantly preterm, or who do not receive a fourth dose of conjugated Hib vaccine may be at increased risk for Hib disease.

Dental therapists' experience in the immediate management of traumatized teeth

The optimal immediate management of traumatized teeth is known to be important for long-term success. One hundred and sixty-seven school dental therapists with General Certificate of Education 'Ordinary' (GCE 'O') level qualification were surveyed on their knowledge and experience on immediate management of dental trauma. The results showed only 41.2% felt comfortable with their present knowledge on the subject. A high proportion of the respondents (94.6%) indicated a need for more knowledge. All therapists concurred on the need to replant a permanent tooth and most (85.1%) agreed that this should be done within 30 min. More than half (54.8%) were not sure of the optimal storage medium for avulsed teeth. Their attitude towards acquiring knowledge in this aspect was good (80.5%) and all would take immediate action to settle appointments for trauma cases.

Control, compare and communicate: designing control charts to summarise efficiently data from multiple quality indicators

Summarising the complex data generated by multiple cross sectional quality indicators in a way that patients, clinicians, managers and policymakers find useful is challenging. A common approach is aggregation to create summary measures such as star ratings and balanced score cards, but these may conceal the detail needed to focus quality improvement. We propose an alternative way of summarising and presenting multiple quality indicators, suitable for use for quality improvement and governance. This paper discusses (1) control charts for repeated measurements of single processes as used in industrial statistical process control (SPC); (2) control charts for cross sectional comparison of many institutions for a single quality indicator (rarely used in industry but commonly proposed for health care); and (3) small multiple graphics which combine control chart signal extraction with efficient graphical presentations for multiple indicators.

Influences of excipients on in vitro release and in vivo performance of tetanus toxoid loaded polymer particles

Protein instability during microencapsulation has been one of the major hurdles of biodegradable polymer particles-based vaccine delivery systems. In the present work, effect of serum albumin, sucrose and sodium bicarbonate on surface morphology, entrapment efficiency, in vitro release and in vivo performance tetanus toxoid (TT) loaded PLA particles were investigated. Use of serum albumin as well as high concentration of protein antigen ( approximately 60mg/ml) helped in protecting the immunoreactivity of the antigen during primary emulsification step of particle formulation. Incorporation of sucrose in the internal aqueous phase led to the reduction in encapsulation efficiency of TT from 43.8+/-4.3% to 27.3+/-3.6% in PLA particles and resulted with formation of particles having irregular surface characteristics. Addition of sodium bicarbonate along with sucrose during primary emulsion led to slight improvement in encapsulation efficiency of TT (34.3+/-3.2%) but affected the in vivo performance in terms of serum anti-TT antibody titers from single point immunization. Restoration of osmotic balance by adding equivalent amount of sucrose in external aqueous phase helped in preventing multiple emulsion instability and subsequently improved the encapsulation efficiency of TT to 63.1+/-4.2%. Maximum entrapment efficiency of TT up to 69.2+/-5.1% was achieved when serum albumin, sucrose and sodium bicarbonate were used in internal aqueous phase and sucrose was used in the external aqueous phase. Polymer particles entrapping tetanus toxoid along with optimal stabilizers showed burst release of immunoreactive antigen (>40% in early period) and elicited high and sustained anti-TT antibody titers from single point intramuscular immunization. Anti-TT antibody titers were further enhanced upon immunization of admixture of PLA particles and alum. Choice and use of stabilizers during particle formulation thus need careful considerations not only to protect the immunoreactivity of the antigen, but also to produce stable, uniform particles for optimal in vivo performances.

Physician Compliance with Tetanus Guidelines for Admitted Versus Discharged Patients

The Advisory Committee of Immunization Practice (ACIP) has established guidelines for tetanus immunoprophylaxis for patients who present to the emergency department (ED) with wounds. We assessed physician compliance with these guidelines for admitted versus discharged patients. The data in this study comes from one institution involved in a recently published prospective observational study that was conducted at 5 university-affiliated hospitals. Of 400 patients enrolled, 65/397 (16.3%) did not receive tetanus immunoprophylaxis in accordance with ACIP guidelines. Emergency physicians were less likely to adhere to the ACIP tetanus guidelines when admitting patients to the hospital. Of patients discharged, (89%), 292 of 325 were treated in accordance with ACIP guidelines compared with 39/71 (55%) of admitted patients (P < 0.001). Admitted patients were also more likely to sustain tetanus-prone wounds. Despite a propensity to present with tetanus-prone wounds, patients admitted to the hospital were less likely to receive tetanus immunoprophylaxis in accordance with ACIP guidelines.

America Academy of Pediatrics Commitee on Infectious Diseases. Prevention of pertussis among adolescents: recommendations for use of tetanus toxoid, reduced diphtheria toxoid, and acellular pertussis (Tdap) vaccine

The purpose of this statement is to provide the rationale and recommendations for adolescent use of tetanus toxoid, reduced diphtheria toxoid, and acellular pertussis (Tdap) vaccines. Despite universal immunization of children with multiple doses of pediatric diphtheria and tetanus toxoids and acellular pertussis (DTaP) vaccine, pertussis remains endemic with a steady increase in the number of reported cases. Two peaks in the incidence of pertussis occur in pediatric patients: infants younger than 6 months of age who are inadequately protected by the current immunization schedule and adolescents 11 through 18 years of age whose vaccine-induced immunity has waned. Significant medical and public health resources are being consumed in postexposure management of adolescent cases, contacts, and outbreaks with little beneficial effect on individuals or the epidemiology of disease. Two Tdap products were licensed in 2005 for use in people 10 through 18 years of age (Boostrix) and 11 through 64 years of age (Adacel). The American Academy of Pediatrics recommends the following: 1. Adolescents 11 to 18 years of age should receive a single dose of Tdap instead of tetanus and diphtheria toxoids (Td) vaccine for booster immunization. The preferred age for Tdap immunization is 11 to 12 years. 2. Adolescents 11 to 18 years of age who have received Td but not Tdap are encouraged to receive a single dose of Tdap. An interval of at least 5 years between Td and Tdap is suggested to reduce the risk of local and systemic reactions; however, intervals of less than 5 years can be used, particularly in settings of increased risk of acquiring pertussis, having complicated disease, or transmitting infection to vulnerable contacts. Data support acceptable safety with an interval as short as approximately 2 years. 3. Tdap and tetravalent meningococcal conjugate vaccine (MCV4 [Menactra]) should be administered during the same visit if both vaccines are indicated. If this is not feasible, MCV4 and Tdap can be administered using either sequence. When not administered simultaneously, the American Academy of Pediatrics suggests a minimum interval of 1 month between vaccines. The rationale for this strategy is to provide direct protection of immunized adolescents. With implementation of vaccine recommendations, indirect benefitalso is likely to extend to unimmunized peers and other age groups. The strategy of universal Tdap immunization at 11 to 12 years of age is cost-effective.

Immunogenicity and safety of four different doses of Haemophilus influenzae type b-tetanus toxoid conjugated vaccine, combined with diphtheria–tetanus–pertussis vaccine (DTP-Hib), in Indonesian infants

Widespread use of Haemophilus influenzae type b (Hib) conjugated vaccine in industrialized countries has resulted in a dramatic decline in the incidence of invasive Hib diseases, but the vaccine's cost has prevented its inclusion in basic immunization programs in developing countries. To overcome this problem, combination with diphtheria-tetanus-pertussis (DTP) vaccine or reduction in the dose of Hib vaccine has been proposed. To evaluate the immunogenicity and adverse reactions from lower doses of Hib-polyribosylphosphate (PRP) conjugated with tetanus toxoid (PRP-T), a double-blind study was conducted in Jakarta, Indonesia, and its suburbs. A total of 1048 infants 6 weeks to 6 months of age received three doses of DTP vaccine combined with the usual 10 microg dose or with a reduced dose of 5, 2.5 or 1.25 microg of PRP-T at two-monthly intervals. Antibodies were measured prior to the first dose and 4-6 weeks following the third dose. Adverse reactions were similar among all four groups. The only significant difference was a higher rate of irritability (p<0.02) and of temperature elevation >38 degrees C (p<0.009) after doses 1 and 2 in the lowest dose group (1.25 microg PRP-T) compared to the other groups. All participants tested had a 4-fold increase in antibodies against all DTP antigens. In addition, after a fourth booster dose of Hib, 99.6% of infants produced >or=0.15 microg/ml of antibody to Hib-PRP, and 96.4% showed levels >or=1.0 microg/ml after primary immunization, level that correlate with short- and long-term immunity, respectively. Antibody titers to the PRP antigen showed no significant differences among dosage groups with the exception of the 5.0 microg group, which had a significantly higher GMC than the 1.25 microg group (p<0.012). This study demonstrates that primary vaccination with half, one-fourth, or one-eighth of the usual dose of PRP-T, combined with DTP vaccine, produces protective immune responses, and has side effects that are comparable to DTP vaccination alone. In these lower dosages, PRP-T conjugate vaccine can lower vaccine costs to a level that is affordable for infant immunization programs in developing countries.

Dysphagia in elderly women: consider tetanus

BACKGROUND

Dysphagia is seldom caused by tetanus; however, it is a common symptom of tetanus. Treating patients with tetanus is a rare event in industrialized countries and awareness is needed to recognize early signs of this serious disease. In Switzerland, the most recently reported tetanus cases occurred in elderly women with insufficient seroprotection.

PATIENTS

We report on three elderly women presenting with dysphagia as an initial symptom of tetanus.

RESULTS

Generalized tetanus was diagnosed in two patients upon admission, the third presented with cephalic tetanus with secondary generalization. All three patients had undetectable levels of tetanus antibodies and had no documented prior tetanus immunizations. Cultures of wound swabs grew Clostridium tetani in all cases. Electromyography was highly suggestive for tetanus in two patients. Treatment involved mechanical ventilation, intravenous benzodiazepine and metronidazole therapy, and active and passive tetanus immunization. The disease had a favorable outcome in two cases and was fatal in one.

CONCLUSION

Tetanus remains a threat in patients with insufficient seroprotection and efforts are needed to improve tetanus immunization in these individuals. Tetanus should be considered in the differential diagnosis of dysphagia.

Immunogenicity and lower dose requirement of polymer entrapped tetanus toxoid co-administered with alum

Low adjuvanticity of microparticles based vaccine formulation necessitates the use of alum along with particles to elicit improved antibody titers from single point immunization. It was observed that antibody response from immunization with admixture of alum and polymer entrapped antigen was dependent on particle size, amount of antigen released during burst phase and dose of microencapsulated antigen. In the animals immunized with polymer entrapped tetanus toxoid (TT) very large particles (50-150 microm) did not elicited high antibody titers where as microparticles in the range 2-8 microm exhibited remarkable improvement in the antibody response. Very small size particles (<2 microm) were also not as effective as 2-8 microm size particles for generation of antibody response. Presence of alum improved the immune response by adsorbing the burst released antigen from the particle surfaces. Role of alum in potentiation of immune response from polymer entrapped TT was highly significant at lower dose regimes. Polymer entrapped TT as little as 0.1 Lf when immunized along with alum generated antibody responses superior to those elicited by 10 Lf soluble antigen. Immunization with admixture of particles and alum generated two to three times higher antibody titer than that observed from immunization with similar single doses of alum adsorbed TT. Single point immunization of admixture of particles entrapped TT and alum generated sustained long lasting antibody responses comparable to two divided doses of alum-adsorbed antigen. Superiority of single dose polymeric formulation in comparison to two divided doses of alum adsorbed TT was more evident at lower doses of TT immunization. This reflected the profound synergistic effect of both the adjuvants at lower doses. Affinity of antibodies generated from single point immunization was comparable to that achieved with two doses of alum adsorbed TT immunization. Particle alone elicited more of IgG2a type antibody where as immunization with admixture of alum and particles improved the overall antibody response and more of Th2 type response.

A novel bivalent morphine/heroin vaccine that prevents relapse to heroin addiction in rodents

Both pre-clinical and clinical studies make feasible the use of vaccines as novel therapeutic medications to treat drug addiction. No reports to date have shown the development of structural models of opiate candidate vaccines for treating human addiction to such compounds. Here we report on the initial development of a novel structural formulation of a bi-valent vaccine against morphine/heroin. This vaccine was able to trigger and establish a high titer antibody response to haptenized drug with antibodies displaying equivalent specificities for both morphine and heroin. Such antibodies did not cross-recognize structurally dissimilar opiate medications. Furthermore, the evaluation of the potential therapeutic effectiveness of this vaccine was targeted to relapse prevention using a schedule of heroin delivery in the rat self-administration model. Antibodies against heroin blocked its reinforcing effects in rodents. The type of carrier protein used in this vaccine allows further evaluation of its potential therapeutic value for preventing relapse to heroin addiction in humans.

Early life T cell responses to pneumococcal conjugates increase with age and determine the polysaccharide-specific antibody response and protective efficacy

Immunization with a tetanus-protein (TT) pneumococcal polysaccharide (PPS) conjugate vaccine (Pnc1-TT) induces protective immunity against lethal pneumococcal infections in neonatal and infant mice, but anti-PPS IgG response and protective efficacy is lower than in adult mice. Here, we show that reduced antibody (Ab) response and protection against infections is directly related to impaired T cell response to the carrier. Whereas spleen cells from adult mice immunized with Pnc1-TT responded with proliferation and IFN-gamma secretion to in vitro stimulation with TT, spleen cells from neonatal and infant mice did not. However, significant, but age dependent, Th2-cytokine responses were observed in mice immunized with Pnc1-TT. Impaired IFN-gamma production upon TT-stimulation in vitro was also reflected in reduced IFN-gamma/IL-5 ratio. The IL--5 response correlated with IgG anti-PPS titers, and the lack of PPS Ab in the majority of neonatal mice was clearly associated with absence of carrier-specific IL-5 production. These results show that immunization with Pnc1-TT induces carrier-specific T cell responses that increase with age and determine the levels of PPS-specific Ab elicited. Whereas a weak and Th2-biased response was observed in neonatal mice, infant mice showed a mixed Th1-Th2 response as observed in adults.

The use of immunomodulators as an adjunct to antituberculous chemotherapy in non-responsive patients with osteo-articular tuberculosis

We studied 51 patients with osteo-articular tuberculosis who were divided into two groups. Group I comprised 31 newly-diagnosed patients who were given first-line antituberculous treatment consisting of isoniazid, rifampicin, ethambutol and pyrazinamide. Group II (non-responders) consisted of 20 patients with a history of clinical non-responsiveness to supervised uninterrupted antituberculous treatment for a minimum of three months or a recurrence of a previous lesion which on clinical observation had healed. No patient in either group was HIV-positive. Group II were treated with an immunomodulation regime of intradermal BCG, oral levamisole and intramuscular diphtheria and tetanus vaccines as an adjunct for eight weeks in addition to antituberculous treatment. We gave antituberculous treatment for a total of 12 to 18 months in both groups and they were followed up for a mean of 30.2 months (24 to 49). A series of 20 healthy blood donors served as a control group.

Twenty-nine (93.6%) of the 31 patients in group I and 14 of the 20 (70%) in group II had a clinicoradiological healing response to treatment by five months.

The CD4 cell count in both groups was depressed at the time of enrolment, with a greater degree of depression in the group-II patients (686 cells/mm3 (sd 261) and 545 cells/mm3 (sd 137), respectively; p < 0.05). After treatment for three months both groups showed significant elevation of the CD4 cell count, reaching a level comparable with the control group. However, the mean CD4 cell count of group II (945 cells/mm3 (sd 343)) still remained lower than that of group I (1071 cells/mm3 (sd 290)), but the difference was not significant. Our study has shown encouraging results after immunomodulation and antituberculous treatment in non-responsive patients. The pattern of change in the CD4 cell count in response to treatment may be a reliable clinical indicator.