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

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

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

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

[Efficacy of vaccine therapy with ribomunil in patients with chronic obstructive pulmonary disease]

AIM

To assess efficacy of vaccine therapy with ribomunil in prevention of exacerbations and prolongation of remission in patients with obstructive pulmonary disease (COPD).

MATERIAL AND METHODS

Fifty three COPD patients were divided into two groups: 28 patients of the study group received ribomunil plus standard therapy; 25 controls received only standard treatment. The examination of the patients included blood count, sputum cytology, external respiration function test, immunological investigation (CD4+, CD8+, CD20+, CD25+ and CD95+; IL-4, IFN-gamma, complement). The examination was made before the treatment, 21 days, 3 and 6 months after its beginning. Ribomunil was given 3 tablets in the morning before meal for 4 days in a week for 3 weeks, 4 days each month for the following 5 months.

RESULTS

As a result of ribomunil treatment lymphocyte subpopulation normalized, immune response shifted to Th-1 dependent immune response, external respiration flow indices improved, remission prolonged.

CONCLUSION

Ribomunil is recommended for wide application in the practice of COPD treatment

Revocation of status of specific products; Group A streptococcus. Direct final rule

The Food and Drug Administration (FDA) is removing the regulation applicable to the status of specific products; Group A streptococcus. FDA is removing the regulation because the existing requirement for Group A streptococcus organisms and derivatives is both obsolete and a perceived impediment to the development of Group A streptococcus vaccines. The regulation was written to apply to a group of products that are no longer on the market. We are taking this action as part of our continuing effort to reduce the burden of unnecessary regulations on industry and to revise outdated regulations without diminishing public health protection. We are issuing the removal directly as a final rule because it is noncontroversial, and there is little likelihood that we will receive any significant adverse comments. Elsewhere in this issue of the Federal Register, we are publishing a companion proposed rule under our usual procedures for notice and comment in the event that we receive any significant adverse comments on the direct final rule. If we receive any significant adverse comments that warrant terminating the direct final rule, we will consider such comments on the proposed rule in developing the final rule.

Prospects for a novel vaccine against tuberculosis

The development of a new and improved vaccine against tuberculosis has in the last 10 years been accelerated tremendously from the completed Mycobacterium tuberculosis genome and the progress in molecular biology. This has resulted in the identification of a large number of antigens with potential in tuberculosis vaccines. The next phase of this work has now started--putting the most relevant molecules back together as fusion molecules and cocktails. This requires carefully monitoring of aspects as immunodominance, recognition in different populations as well as the influence of different adjuvants and delivery systems. The most advanced of these vaccines such as the fusion between ESAT6 and Ag85B have been evaluated in a range of animal models including non-human primates and are now entering into clinical trials. For these vaccines to be successfully implemented in future vaccination programmes it is necessary to understand the immunological background for the failure of BCG and optimize the vaccines for their ability to boost the immuno-response primed by BCG.

Bacillus anthracis edema toxin inhibits Staphylococcus aureus enterotoxin B effects in vitro: a potential protein therapeutic?

Various in vitro effects of staphylococcal enterotoxin B (SEB) on human peripheral blood mononuclear cells were mitigated by Bacillus anthracis edema toxin. In particular, levels of some SEB-induced cytokines (tumor necrosis factor alpha, gamma interferon) and chemokines (monocyte chemoattractant protein 1, macrophage inflammatory protein 1 alpha [MIP-1alpha], MIP-1beta) were significantly diminished or even nonexistent, depending upon the timing of edema toxin administration. Overall, these results suggest a novel use of B. anthracis edema toxin against a bacterial superantigen.

SEB combined with IL-1ra could prolong the survival of the rat allografts in high-risk corneal transplantation

PURPOSE

To determine whether the superantigen Staphylococcal enterotoxin B (SEB) combined with interleukin-1 receptor antagonist (IL-1ra) prolong allograft survival better than individual agents in high-risk corneal transplantation in a rat model.

METHODS

Fisher 344 donor corneas were transplanted into Lewis recipients. High-risk transplantation meant that the transplants were sutured into the recipient beds with corneal neovascularization induced by placing three interrupted sutures in the host cornea. All of the recipients were divided in blinded fashion into four groups. Group I was injected with saline buffer. Group II was injected intraperitoneally with 0.2 mL SEB (75 microg/kg) at 4-day intervals on three occasions before transplantation. Group III was injected with 0.1 mL IL-1ra (1 mg/mL) subconjunctivally from the first day after transplantation for 2 weeks. Group IV received both SEB and IL-1ra. All transplants were evaluated for signs of rejection for 4 weeks after surgery. Ten days after transplantation, two recipients in each group were sacrificed for histopathological and immunological evaluation.

RESULTS

The mean survival time of the allografts in the control group was 5.89 +/- 0.79 days; in SEB group, 10.70 +/- 2.52 days; in IL-1ra group, 8.25 +/- 0.71 days; in the SEB and IL-1ra group, 17.36 +/- 2.39 days. CD4+ and CD8+ lymphocyte infiltration into the allografts and the percentage of the lymphocytes in the spleen and mandibular lymphatic nodes was significantly decreased among the treated groups with dampened lymphocyte reactivity. The SEB plus IL-1ra combination group showed the strongest inhibition.

CONCLUSION

SEB and IL-1ra are most effective in combination to treat high-risk corneal transplants.

Preclinical evaluation of superantigen (staphylococcal enterotoxin B) in the intravesical immunotherapy of superficial bladder cancer

Superantigens are potent activators of T lymphocytes; therefore, their characteristics can be exploited in diseases where immunomodulation is known to be effective. In this study, we evaluated a new approach for the intravesical therapy of superficial bladder cancer. We investigated in coculture experiments if staphylococcal enterotoxin B (SEB)-activated PBMCs are able to induce apoptosis in human transitional cell carcinoma (TCC) cells. Additionally, we tested the toxicity and efficacy of SEB dissolved in NaCl 0.9% administered intravesically once weekly for 6 weeks in a rat bladder cancer model. To validate the coculture in vitro findings, we evaluated tumor stage, grade, apoptotic cells in the urothelium and stroma of the bladder and infiltration of the bladder wall by lymphocytes, macrophages and mononuclear cells. Coculture experiments revealed that SEB-activated PBMCs are able to kill TCC cells by inducing apoptosis. The intravesical toxicity study with a maximum dose of 100 microg/ml SEB demonstrated no side effects. In the intravesically SEB-treated animals (10 microg/ml), only 3 tumors remained vs. 15 persisting tumors in the control group. The remaining tumors of the therapy group showed a significant amount of apoptosis and granulocytes, mainly in the urothelium, whereas no relevant apoptosis or infiltration of the bladder with lymphocytes or macrophages was found in the control group. These preclinical findings suggest that SEB might be an interesting candidate for further clinical evaluation.

A novel peptide screened by phage display can mimic TRAP antigen epitope against Staphylococcus aureus infections

Staphylococcus aureus is a major human pathogen. Pathogenic effects are largely due to production of bacterial toxins, whose synthesis is controlled by an mRNA molecule termed RNAIII. The S. aureus protein called RAP (RNAIII-activating protein) is secreted and activates RNAIII production by inducing the phosphorylation of its target protein TRAP (target of RAP). Antibodies to TRAP have been shown to suppress exotoxin production by S. aureus in vitro, suggesting that TRAP may be a useful vaccine target site. Here we showed that a peptide TA21 was identified by screening a phage display library using anti-TRAP antibodies. Mice vaccinated with Escherichia coli engineered to express TA21 on their surface (FTA21) were protected from S. aureus infections, using sepsis and cellulitis mice models. By sequence analysis, it was found that the TA21 is highly homologous to the C-terminal sequence of TRAP which is conserved among S. aureus and Staphylococcus epidermidis, suggesting that peptide TA21 may be a useful broad vaccine to protect from infection caused by various staphylococcal strains.

Membrane type-1 matrix metalloproteinase (MT1-MMP) protects malignant cells from tumoricidal activity of re-engineered anthrax lethal toxin

Protective antigen (PA) and lethal factor (LF) are the two components of anthrax lethal toxin. PA is responsible for interacting with cell receptors and for the subsequent translocation of LF inside the cell compartment. A re-engineered toxin comprised of PA and a fusion chimera LF/Pseudomonas exotoxin (FP59) is a promising choice for tumor cell surface targeting. We demonstrated, however, that in vitro in cell-free system and in cultured human colon carcinoma LoVo, fibrosarcoma HT1080 and glioma U251 cells membrane type-1 matrix metalloproteinase (MT1-MMP) cleaves both the PA83 precursor and the PA63 mature protein. Exhaustive MT1-MMP cleavage of PA83 in vitro generates several major degradation fragments with an N-terminus at Glu40, Leu48, and Gln512. In cultured cells, MT1-MMP-dependent cleavage releases the cell-bound PA83 and PA63 species from the cell surface. As a result, MT1-MMP expressing cells have less PA63 to internalize. In agreement, our observations demonstrate that MT1-MMP proteolysis of PA makes the MT1-MMP-expressing aggressive invasive cells resistant to the cytotoxic effect of a bipartite PA/FP59 toxin. We infer from our studies that synthetic inhibitors of MMPs are likely to increase the therapeutic anti-cancer effect of anthrax toxin. In addition, our study supports a unique role of furin in the activation of PA, thereby suggesting that furin inhibitors are the likely specific drugs for short-term therapy of anthrax infection.

Effects of Oral Bacterial Immunotherapy in Children with Atopic Eczema/Dermatitis Syndrome

BACKGROUND

Atopic eczema/dermatitis syndrome (AEDS) is a chronic inflammatory skin disease, affecting 10-20% of children and 1-3% of adults. The purpose of this pilot study was to assess the clinical and anti-inflammatory effect of bacterial and ribosomal immunotherapy with Immucytal (Pierre Fabre Médicament, France) in children with AEDS.

METHODS

Seventeen children with allergic and non-allergic forms of AEDS (AAEDS and NAAEDS, respectively), graded moderate to severe (Severity Scoring of Atopic Dermatitis [SCORAD] index of >25), received ribosomal immunotherapy (Immucytal) once daily according to the standard treatment regimen (4 consecutive days a week for 3 weeks, and then 4 consecutive days a month for 4 months). We assessed the clinical status of AEDS using the SCORAD index at baseline, and after 8 and 20 weeks of treatment. Furthermore, peripheral blood from patients was examined for the frequencies of CD4+ cells expressing interferon (IFN)-gamma and interleukin (IL)-4 using flow cytometry.

RESULTS

There was a progressive and significant clinical improvement of AEDS, confirmed by a reduction of the SCORAD index over time in both AEDS forms (p < 0.01). Pooled data from the two groups showed that the mean baseline index of 43 was reduced to 17 after treatment. Overall, these data indicate a marked improvement in total clinical severity of AEDS (-62%). Flow cytometry analysis showed that frequencies of the two CD4+ T cell subsets did not differ significantly from the beginning to the end of the study in both forms of AEDS. However, the percentage of CD4+ cells expressing IL-4 in children with AAEDS tended to decrease by the end of treatment with ribosomal immunotherapy. Clinical and laboratory data confirmed that immunotherapy was well tolerated.

CONCLUSIONS

The results of this pilot investigation suggest that ribosomal immunotherapy may be beneficial in the management of AEDS in children, and that this could be at least partially explained by a role in restoring the type 2 helper-T cell imbalance seen in allergic patients. Placebo-controlled, randomized clinical trials are recommended in order to confirm these findings.

[Experience of ribomunyl application in patients with chronic bronchitis]

The authors performed clinical and immunological evaluation of efficacy of treatment of patients with occupational chronic bronchitis (CB) working in contact with pneumotropic pollutants, including airway irritants and dusts. The complex therapy included an immune-correcting agent of bacterial origin, ribomunyl. The indicators to the drug administration were remission or moderate manifestations of the disease with disturbances of mucosal immunity, both isolated (imbalance of IgA, IgG and salivary lysozyme) or combined with systemic immunity disorder (decrease of neutrophilic phagocyte activity, serum IgM and IgG, and the number of T-lymphocytes). The course lasted 3 weeks; the regimen was standard: 3 tablets in the morning before meals 4 days a week. During the whole period of immune correction the patients were under clinical observation; respiratoryfunctions (RF), bronchial hyperactivity, and immune status were evaluated prior to and after the treatment. After the treatment with ribomunyl most patients displayed improvement of the symptoms and FF parameters. The study found significant improvement of a range of immunological parameters: reduction of the imbalance of salivary protective factors, elevation of the phagocyte activity of peripheral blood neutrophils, and a tendency towards increase of IgG and blood T-lymphocyte levels. The results show that clinical, functional and immune parameters normalized simultaneously, with the most evident matching in salivary immunity. The authors conclude that ribomunyl is efficient in treatment of occupational CB when administered with taking individual disturbances of mucosal and systemic immunity into account.

Intrapleural Staphylococcal Superantigen Induces Resolution of Malignant Pleural Effusions and a Survival Benefit in Non-Small Cell Lung Cancer

BACKGROUND

Malignant pleural effusion (MPE) may occur in up to 50% of patients with non-small cell lung cancer (NSCLC). The majority of these patients have a poor performance status and a dismal prognosis, with survival duration ranging from 2 to 3 months. Since these patients are typically symptomatic from their MPE, prompt treatment is required. Patients with symptomatic MPE from NSCLC and poor performance scores (Eastern Cooperative Oncology Group [ECOG] score >/= 2, Karnofsky performance status [KPS] score < 50) are generally not offered systemic chemotherapy. Treatment is palliative and includes intrapleural catheter drainage or chemical pleurodesis with talc, doxycycline, or bleomycin. None of the latter modalities prolong survival.

OBJECTIVE

Our goal was to investigate the toxicity and therapeutic effect of a new therapeutic agent, Staphylococcus aureus superantigen (SSAg), a powerful T-cell stimulant administered intrapleurally to unselected, consecutive patients with MPE from NSCLC (stage IIIb with pleural effusion) and a poor performance status. By providing direct access of the SSAg to the bronchial and mediastinal lymphatics, we predicted that intrapleural administration of SSAg would induce resolution of MPE and prolong survival in this population with advanced NSCLC and a limited prognosis.

METHODS

Fourteen consecutive, unselected patients with MPE from NSCLC and a median pretreatment KPS score of 40 (range, 10 to 60) received pleural instillation of SSAg, 100 to 400 pg, once or twice weekly (mean, 3.7 +/- 1.3 treatments [+/- SD]) until the pleural effusions resolved. They were evaluated for drug toxicity, resolution, duration of MPE, and survival.

RESULTS

Other than mild fever (maximum grade 2), toxicity of SSAg treatment was trivial and notably devoid of respiratory distress or hypotension. Eleven patients had a complete response (CR), and 3 patients had a partial response of their MPE. In 12 patients, the response endured for > 90 days, with a median time to recurrence of 5 months (range, 3 to 23 months). The median survival for the SSAg-treated group was 7.9 months (range, 2 to 36 months; 95% confidence interval [CI], 5.9 to 11.4 months), compared to a median survival of 2.5 months (range, 0.1 to 57 months; 95% CI, 1.3 to 3.4 months) for 18 consecutive, unselected patients with MPE from NSCLC (stage IIIb) treated with talc poudrage (p = 0.044). Survival duration of all 14 SSAg-treated cases and 13 talc-poudrage-treated patients with comparable pretreatment KPS (range, 10 to 60; median, 40 and 30, respectively), and distribution (p = 0.5) was 7.9 months (95% CI, 5.9 to 11.4 months) and 2.0 months (95% CI, 0.4 to 2.9 months), respectively (p = 0.0023). Nine of 14 patients treated with SSAg survived > 6 months, 4 patients survived > 9 months, and 3 patients survived > 350 days. One of the patients in the CR group has survived 36 months. None of the 13 talc-treated patients survived > 6 months.

INTERPRETATION

In 14 unselected, consecutive patients with MPE from NSCLC and poor pretreatment performance (median KPS of 40), the intrapleural administration of SSAg was efficacious in resolving the MPE without any clinically important adverse effects. SSAg-treated patients with a median KPS of 40 (range, 10 to 60) had a median survival that exceeded that with talc poudrage, and was comparable to current systemic chemotherapy used in patients with KPS >/= 70 status. SSAg treatment is simple to perform, minimally invasive, and does not require hospital time. It may be an attractive alternative to existing palliative modalities for stage IIIb patients with MPE and poor performance who are not candidates for systemic chemotherapy.

Immunisation against plague by transcutaneous and intradermal application of subunit antigens

We have investigated immunological responses in BALB/c mice following transcutaneous (TC) delivery of fraction 1 (F1) and V subunits from Yersinia pestis in conjunction with an enterotoxin-derived adjuvant (cholera toxin, CT). It was found that two or more TC applications of F1 and V subunits (admixed with cholera toxin) served to elicit significant levels of anti-F1 and V antibodies in the serum of immunised mice. IL-6 secretion from cultured splenocytes derived from immunised mice indicated that a single TC application of F1 and V subunits (admixed with cholera toxin) conferred a cell-mediated response. As compared with intranasal or direct intradermal injection of F1 and V, the numbers of F1/V-specific antibody-forming cells in the spleens of animals immunised by TC application of F1 and V (admixed with CT) was relatively low. It was noted that TC application of F1 and V admixed with CT was very effective for priming responses that were boosted by intranasal or intradermal routes. Similarly, it was found that TC application of F1 and V admixed with CT could be used to efficiently boost pre-existing responses engendered by intradermal injection or intranasal instillation of F1 and V. In order to assess if TC application of F1 and V admixed with CT could protect experimental animals from plague, immunised mice were injected with a virulent strain of Y. pestis. It was found that two TC applications of F1 and V admixed with CT conferred only limited protection against 10(2) MLDs. However, three TC applications of F1 and V admixed with CT conferred solid protection against 10(2) MLDs. Hence we have shown, for the first time, that TC application of F1 and V admixed with CT can protect animals against challenge with a virulent strain of plague causing bacteria. These data suggest that transcutaneous immunisation may be a simple and non-invasive method for immunising individuals against plague.

Efficacy of a topical suspension of bacterial antigens for the management of recurrent eczema in children

BACKGROUND

The aim of this study was to compare the efficacy and safety of a topical suspension of bacterial antigens for the management of recurrent eczema in children.

MATERIAL/METHODS

Eighty pediatric patients, aged between 2 and 6 years, with a history of recurrent external auditory eczema, were enrolled in this study. Congenital immune deficiencies, treatment with corticosteroids, immunostimulant or immunosuppressive agents in the past 6 months, and bronchopulmonary disease were considered as exclusion criteria. The patients were randomized to receive topical suspension of bacterial antigens (Lantigen B) (Group A) or placebo (physiological solution) (Group B). The efficacy parameters were evaluated before, at the end of, and one year after the beginning of the therapy. All the children underwent clinical examinations, blood test, skin prick tests (SPT), and clinical evaluation using the clinical score proposed by Rajka and Langeland, considering the intensity, extent, and course of lesions.

RESULTS

In Group A, using the statistical Wilcoxon test, we saw an improvement in the clinical items measured. It is important to consider that the patients were allowed to receive concomitant medications to treat acute episodes, which may have partially contributed to the positive results obtained.

CONCLUSIONS

A topical suspension of bacterial antigens was significantly more effective than placebo in the treatment of recurrent eczema in children.

Ribosomal immunostimulation: assessment of studies evaluating its clinical relevance in the prevention of upper and lower respiratory tract infections in children and adults

OBJECTIVE

To review the efficacy of the ribosomal immunostimulant Ribomunyl in preventing upper and lower respiratory tract infections.

DESIGN AND SETTING

Review of studies of 3 and 6 months' duration comprising part of the international registration file.

PATIENTS

Data from 2117 patients (1215 children and 902 adults); ribosomal immunostimulant n = 1062, placebo n = 1055.

RESULTS

Nineteen randomised, double-blind, placebo-controlled clinical trials were performed between 1983 and 1994 in Europe. In children with ear-nose-throat (ENT) infections, 3 months' ribosomal immunostimulant treatment significantly decreased the mean number of recurrences (27-68% reduction), and reduced the duration of infection (28-66% reduction) and antibacterial requirement (29-60% reduction). Ribosomal immunostimulant was similarly effective in children with ENT and bronchopulmonary infections, reducing the mean number of recurrences by 32-61% compared with placebo. In children with otitis media, ribosomal immunostimulant reduced recurrences by 10-53% and also reduced the duration of infection, antibacterial use and local surgery requirement. Results obtained from studies of 6 months' duration confirmed or extended these results. In adult patients with ENT or mixed respiratory infections, ribosomal immunostimulant produced similar reductions to those seen in children for recurrent infections (54-78% reduction), duration of infection (42-79% reduction) and antibacterial use (38% reduction).

CONCLUSIONS

These results clearly demonstrate that ribosomal immunostimulant is effective in preventing and in reducing upper and lower respiratory tract infections in children and adults.

Short ribosomal prophylaxis in the prevention of clinical recurrences of chronic otitis media in children

The aim of this study was to compare the efficacy and the safety of a short oral ribosomal immunotherapy (Immucytal) in the prevention of chronic otitis media in children. Seventy-two patients were enrolled in this study, 41 males and 31 females, aged between 6 and 14 years, with an history of recurrent otitis media. Patients were randomised to receive Immucytal (group A) or placebo (group B) according to the following protocol: one tablet daily in the morning 8 days per month for three consecutive months. Immucytal and placebo were identical in shape and size, in order to maintain double-blind conditions. The efficacy parameters were (evaluated before, at the end and 6 months after the beginning of the therapy): clinical score; changes in immunological parameters; patient's parents assessment of symptoms on a scale from 0 (much worse) to 4 (much improved) and hearing tests. Patients of group A, had an improvement of clinical items measured, serum concentrations of immunoglobulins, subjective patient's parents assessment of symptoms and hearing tests. For all evaluations, a significant difference between treatment groups was found. Using this dosage and posology (shorter than others) the beneficial effects of Immucytal were maintained until the end of the 6-month study period.

Intranasal immunization of humans with Streptococcus mutans antigens

To evaluate the effectiveness of a low dose of soluble or liposomal (L) glucosyltransferase-enriched preparation (E-GTF) in inducing mucosal immune responses after intranasal immunization, 12 adults were immunized on days 0 and 7 by the IN route with 62.5 microg of soluble E-GTF or L-E-GTF. An increase in the mean salivary IgA anti-E-GTF response (P < 0.03) was seen in the L-E-GTF but not the soluble E-GTF group. A significant increase (P < 0.05) in the mean specific IgA antibody activity was also seen in nasal wash from both groups. Although the nasal wash responses were higher in the L-E-GTF than in the soluble E-GTF group, they were not significantly different. The soluble E-GTF immunized group showed a higher serum IgG response than the L-E-GTF immunized group on day 90 (P < 0.05). These results indicate that as little as 62.5 microg of E-GTF, when given by the intranasal route, induced an IgA response in secretions.

Immunogenicity of a three-component acellular pertussis vaccine administered at birth

OBJECTIVE

To evaluate within the first 6 months of birth the immunogenicity of a 3-component acellular pertussis (aP) vaccine containing filamentous hemagglutinin (FHA), pertactine (PRN), and genetically detoxified pertussis toxin (PT) in infants who received a dose of vaccine at birth, in addition to the recommended schedule administered at 3, 5, and 11 months. Furthermore, we investigated the influence of maternal antibodies on aP vaccine response.

METHODS

We used enzyme-linked immunosorbent assay to evaluate immunoglobulin G antibody levels in 45 infants immunized at birth and at 3, 5, and 11 months (group 1) and in 46 infants immunized at the ages of 3, 5, and 11 months (group 2). All mothers were also tested at delivery.

RESULTS

At the age of 5 months the geometric mean titer of anti-PT, anti-FHA, and anti-PRN was significantly greater in group 1 (who had received 2 doses) than in group 2 (1 dose). At 6 months geometric mean titers were significantly higher in group 1 than in group 2 for anti-PRN and anti-FHA, whereas no significant differences were observed for anti-PT.

CONCLUSIONS

Immunization at birth may be important for an earlier prevention of the pertussis disease in infants under 6 months, especially in Italy, where the recommended ages for aP vaccine administration are 3, 5, and 11 months.

Effect of vaccination therapy for acne, using a staphylococci antigenic complex in combination with clindamycin

A group of 46 patients with acne vulgaris were prescribed clindamycin in combination with a vaccination therapy using a staphylococci antigenic complex (Polystafana; Sevapharma, Czechia). Acne papulopustulosa was diagnosed in 36 patients and acne indurata in 10 patients. The clinical effect of clindamycin and Polystafana was determined on the basis of the regression of the inflammatory manifestation of acne: regression by 0-30% was considered unsuccessful, by 30-80% satisfactory, and above 80% excellent; the immunomodulation effect of the treatment was evaluated in parallel. The clinical effect was excellent in 21 patients with acne papulopustulosa and in 6 with acne indurata; it was accompanied by pronounced immunomodulation effect as both cellular and humoral immunity was also tended to return to normal values. A satisfactory clinical effect was observed in 15 patients with acne papulopustulosa, whose cellular immunity component was also stimulated. Only 4 patients with acne indurata failed to respond successfully. These were the patients who showed a pronounced deficit of the cellular immunity component persisting even after the treatment. The administration of clindamycin in combination with Polystafana vaccination can be recommended as an effective means for the treatment of acne vulgaris.

Nonsecreted bacterial proteins induce recall CD8 T cell responses but do not serve as protective antigens

Secreted or nonsecreted Ag expressed by recombinant Listeria monocytogenes can prime CD8 T cells. However, Ag-specific memory CD8 T cells confer protection against bacteria secreting Ag, but not against bacteria expressing the nonsecreted form of the same Ag. This dichotomy may be explained by a long-standing hypothesis that nonsecreted Ags are less effective than secreted Ags at inducing a protective immune response at the onset of infection. We tested this hypothesis by examining whether these two different forms of Ag induce different primary and secondary CD8 T cell responses. The primary responses to secreted and nonsecreted Ags expanded and contracted almost synchronously, although the responses to nonsecreted Ags were of lower magnitude. These results demonstrate that the kinetics of the CD8 T cell response are similar regardless of whether Ag is accessible to the endogenous MHC class I pathway or can only be presented through cross-presentation. No differences were detected in the CD8 T cell recall response to L. monocytogenes expressing secreted or nonsecreted Ags. Nonsecreted Ags are as effective as secreted Ags at the induction of a rapid recall response by memory CD8 T cells. Thus, the inability of nonsecreted bacterial proteins to serve as protective Ags cannot be attributed to a defective CD8 T cell response.

Protection against plague following immunisation with microencapsulated V antigen is reduced by co-encapsulation with IFN-gamma or IL-4, but not IL-6

We have investigated intranasal delivery of novel vaccines for plague, based on poly-L-lactide (PLLA) microencapsulated recombinant V antigen (rV) of Yersinia pestis. Microspheres containing rV alone or co-encapsulated with the cytokines IFN-gamma, IL-4 or IL-6 were administered in a two-dose regimen and antibody responses and protective efficacy were monitored. All treatment groups stimulated high rV-specific antibody titres in serum, predominantly of the IgG1 isotype, which were maintained over several months. There was evidence of both IgG and IgA responses in lung samples from all groups. Formulations based on rV antigen alone or rV co-encapsulated with IL-6 provided complete protection against systemic challenge with Y. pestis strain GB; however protective efficacy was impaired by co-encapsulating either IFN-gamma or IL-4 with rV.