Antibodies against Haemophilus influenzae type b capsular polysaccharide and tetanus toxoid before and after a booster dose of the carrier protein nine years after primary vaccination with a protein conjugate vaccine

IgG antibodies against Haemophilus influenzae type b (Hib) capsular polysaccharide (CPS) and tetanus toxoid (TT) were measured for 53 children, 10 years of age, before and 1 month after a booster dose of diphtheria-tetanus vaccine (DT). All children had been vaccinated at 3, 5 and 12 months of age with DT and a Hib-TT conjugate. Geometric mean concentrations of Hib CPS serum IgG antibody were 4.16 and 4.30 microg/mL before and after the DT booster, respectively. The geometric mean concentration of TT IgG antibody increased from 0.09 IU/mL to 4.58 IU/mL (P < 0.001). Hib CPS IgG levels remained well above protective titers for 9 years after 3 doses of Hib-TT appropriately spaced in infancy. A booster dose of TT did not affect Hib CPS antibody concentrations but induced a pronounced IgG response against TT.     

Reduced immunogenicity of diphtheria and tetanus toxoids when combined with pertussis toxoid

The effect of pertussis toxoid on the immunogenicity of diphtheria and tetanus toxoids (DT) was studied during a double blind efficacy trial of an acellular pertussis vaccine. Infants received DT with or without pertussis toxoid at 3, 5 and 12 months of age. Geometric mean concentrations were higher in the DT than in the DT-pertussis toxoid group 1 month (diphtheria toxoid 4.76 versus 3.58 IU/mL, P = 0.009; tetanus toxoid 4.42 versus 2.66 IU/mL, P < 0.0001) and 2 years after the third injection (diphtheria toxoid 0.15 versus 0.10 IU/mL, P < 0.0001; tetanus toxoid 0.38 versus 0.18 IU/mL, P < 0.0001). Pertussis toxoid causes a small but significant reduction of the immunogenicity of diphtheria toxoid and tetanus toxoid.     

Diphtheria, tetanus and pertussis antibodies in 10-year-old children before and after a booster dose of three toxoids: implications for the timing of a booster dose

In an open study, 502 10-year-old children, who had received primary vaccination against diphtheria and tetanus in infancy and had varying histories of pertussis disease and vaccination, were vaccinated with diphtheria-tetanus vaccine (DT) alone or with the addition of 20 µg or 40 g of pertussis toxoid. Diphtheria toxin neutralising antibodies, pertussis toxin IgG and tetanus toxoid IgG antibodies were measured before and 1 month after the booster. All toxoids were highly immunogenic. In pertussis toxoid recipients, median levels of pertussis toxin IgG increased to 16.5 U/ml (DTaP20) and to 36 U/ml (DTaP40) in children with non-detectable (<1 U/ml) antibodies before vaccination and to >400 U/ml in children (both DTaP20 and DTaP40) with detectable antibodies before vaccination. A total of 60 children (12%) with non-detectable (<0.01 IU/ml) diphtheria antibodies and 36 children (7%) with non-detectable (<0.01 IU/ml) tetanus antibodies before the booster had lower median antibody concentrations post-vaccination than children with detectable antibodies before the booster (diphtheria: 5.12 vs. 20.48 IU/ml; tetanus: 4.0 vs. 10.0 IU/ml). There were no differences in diphtheria and tetanus antibodies after vaccination between children who did and did not receive pertussis toxoid. Conclusion:10-year-old children with non-detectable diphtheria and tetanus antibodies before the booster had lower post-vaccination antibodies than those with detectable antibodies before the booster indicating a poor immunological memory. Addition of pertussis toxoid to diphtheria-tetanus vaccine did not affect the antibody responses to diphtheria and tetanus toxoids when the three toxoids were combined as a booster. Even though immunity to diphtheria and tetanus was only estimated by surrogate markers (serum antitoxin antibodies) the results indicate that a lower age for the booster dose of diphtheria-tetanus vaccine or diphtheria-tetanus acellular pertussis vaccine should be considered.     

Immune deficiencies following cancer treatment in children

The aim of this study was to determine serum immunoglobulins, IgG subclasses, lymphocyte subsets, and serum protective antitoxin levels of tetanus and diphtheria, and to investigate specific antibody response to tetanus and diphtheria vaccines in children with cancer who have been treated for leukemias and solid tumors. Forty patients with different types of childhood malignancies were enrolled in this study and their lymphocyte subsets, serum Ig A, M, G and IgG subclass concentrations were determined at completion of chemotherapy and 6 months later. We measured serum diphtheria (D) and tetanus (T) antitoxin levels and investigated specific antibody responses against DT vaccines at 6 months. Only the leukemic children had low CD19+ cells at completion of chemotherapy and 6 months later. The patients with solid tumors had reduced CD4+ cells, but increased natural killer cells at completion of chemotherapy. Serum IgA and IgM levels were decreased in leukemic patients after chemotherapy. There were no IgG subclass deficiency. Forty-two per cent of the patients did not have protective serum T antitoxins. All patients produced high levels of DT antibodies by vaccination. Immune system changes recover by 6 months after cancer therapy in children. Children with solid tumors, as well as leukemias, should be followed-up in terms of immune deficiencies. A repeat dose of tetanus toxoid should be recommended at 6 months.     

Clinical reactions and immunogenicity of the BIKEN acellular diphtheria and tetanus toxoids and pertussis vaccine in 4- through 6-year-old US children.

OBJECTIVE--To compare the immunogenicity and reactogenicity of a two-component acellular pertussis vaccine with a whole-cell diphtheria and tetanus toxoids and pertussis vaccine (W-DTP) when administered as a booster to children 4 through 6 years of age. DESIGN--This was a randomized, double-blind study. SETTING--Children in this study were from three general pediatric practices (two were private, one was university-affiliated). PARTICIPANTS--Three hundred and sixteen 4- through 6-year-old children who had received four previous W-DTP immunizations at the recommended times were studied. SELECTION PROCEDURES AND INTERVENTIONS--Children were randomly assigned in a 1:3 ratio to receive either W-DTP or one of three lots of acellular diphtheria and tetanus toxoids and pertussis vaccine (A-DTP). The A-DTPs contained 3.75 micrograms each of lymphocytosis promoting factor and filamentous hemagglutinin protein nitrogen per 0.5 mL and the same concentrations of diphtheria and tetanus toxoids as W-DTP. Serum samples were obtained on the day of immunization and 4 to 6 weeks later. Adverse reactions were recorded by parents at 6, 24, 48, and 72 hours. MEASUREMENTS AND RESULTS--An indirect enzyme-linked immunosorbent assay (ELISA) method determined IgG antibody response to lymphocytosis promoting factor, filamentous hemagglutinin, and tetanus toxoid; a CHO cell assay measured neutralizing antibodies to pertussis toxin; and serum neutralization on VERO cells assayed diphtheria antitoxin. One month after booster doses were administered, the geometric mean antibody levels for A-DTP vs W-DTP were IgG filamentous hemagglutinin, 362 vs 104 ELISA U/mL; IgG lymphocytosis promoting factor, 408 vs 81 ELISA U/mL; CHO cell, 210 vs 107; diphtheria, 21.7 vs 12.1 U/mL; and tetanus, 2.86 vs 2.04 Eq/mL. Following immunization with A-DTP, local and systemic adverse experiences were 30% to 50% and 20% to 30% fewer, respectively, as compared with W-DTP. CONCLUSIONS--The BIKEN A-DTP vaccine used in this study demonstrates enhanced immunogenicity to lymphocytosis promoting factor, filamentous hemagglutinin, and other measured antigens and less reactogenicity compared with licensed W-DTP [corrected].     

Clinical and immunologic responses to the capsular polysaccharide of Haemophilus influenzae type b alone or conjugated to tetanus toxoid in 18- to 23-month-old children

The safety and immunogenicity of Haemophilus influenzae type b (Hib) capsular polysaccharide (CPS) alone, or covalently bound to tetanus toxoid in saline solution (Hib-TT) or adsorbed onto AI(OH)3 (Hib-TT ads), were evaluated after one injection into 18- to 23-month-old healthy children in Sweden. No side reactions were elicited by Hib CPS; side reactions elicited by the two conjugates were similar and comparable to those reported for diphtheria and tetanus toxoids adsorbed. Hib-TT was the most immunogenic of the three vaccines, eliciting about 10-fold higher antibody levels than Hib CPS; of 28 vaccinees, all had greater than 1.0 microgram Ab/mL serum after immunization with Hib-TT. Increases of Hib CPS antibodies within immunoglobulin classes induced by the three vaccines were, in decreasing order, IgG greater than IgM greater than IgA. Within IgG subclasses, rises in IgG1 Hib CPS antibodies were the most frequent, followed by IgG2; some vaccinees with high postimmunization levels also had rises in IgG3 and one in IgG4. Immunization-induced Hib CPS antibodies were bactericidal. Hib-TT also elicited higher levels of tetanus toxoid antibodies than Hib-TT ads; these tetanus toxoid antibodies neutralized tetanus toxin in vivo.     

Local reactions and IgE antibodies to pertussis toxin after acellular diphtheria-tetanus-pertussis immunization

Local reactions and pertussis toxin specific immunoglobulin E antibodies (PT-IgE) were investigated in healthy children following primary and booster immunization with a combined diphtheria tetanus acellular pertussis vaccine (DTPa) including pertussis toxin, filamentous haemagglutinin and pertactin. A primary series of DTPa was administered to 150 infants, and 104 of them received a booster dose of DTPa combined with inactivated polio vaccine at 2 years of age. PT-IgE was measured in serum samples from 72 children using a modified nitrocellulose RAST. Primary immunization was associated with low incidence of local reactions (1%–5%). After the booster dose 21% of children had a local reaction ≥20 mm. Local reactions after the booster dose tended to be more common in children who had experienced reaction at primary immunization. PT-IgE was detected in 18% and 86% of children following primary and booster vaccinations, respectively. Allergic and non-allergic children did not differ in PT-IgE responses. After primary immunization, elevated PT-IgE levels were found more often in children with a family history of allergy than in those without known allergy in the family. Children with local reactions had significantly higher pre- and post-booster PT-IgE levels and median post-booster pertactin IgG and diphtheria-IgG levels than children without local reactions. Conclusion Acellular pertussis immunization induces IgE antibodies to pertussis toxin, especially after booster vaccination. The higher median pre- and post-booster levels of pertussis toxin specific immunoglobulin E and post-booster levels of IgG to pertactin and diphtheria in children with local side-effects reflect a multifactorial immunological mechanism of such reactions. Received: 21 May 1999 / Accepted: 13 June 1999     

Immunogenicity of Haemophilus influenzae oligosaccharide-protein and polysaccharide-protein conjugate vaccination of children at 4, 6, and 14 months of age

At 4 and 6 months of age, 118 infants were vaccinated with either one of two Haemophilus influenzae type b capsular polysaccharide-protein conjugate vaccines: 72 infants received the polysaccharide coupled to diphtheria toxoid (PRP-D group), and 46 infants received polysaccharide-derived oligosaccharides coupled to CRM197 protein, a nontoxic mutant form of diphtheria toxin (HbOC group). A third dose of the same vaccine was given to 40 children in the PRP-D group and 25 children in the HbOC group at 14 months of age. Antibodies to the H influenzae type b capsular polysaccharide were measured by Farr-type radioimmunoassay in serum samples taken before each vaccination and 1 month after the second and the third doses. Adverse reactions monitored by a questionnaire were mild. After two vaccine doses, the geometric mean concentration of antibodies to H influenzae type b polysaccharide increased from 0.07 micrograms/mL in the prevaccination samples to 0.63 micrograms/mL in the PRP-D group and to 4.32 micrograms/mL in the HbOC group. In the following 7 months, the geometric mean concentrations declined to 0.38 and 1.12 micrograms/mL, respectively. The booster dose given at 14 months elicited a strong antibody response in both groups (to geometric mean concentrations of 29.7 and 58.3 micrograms/mL, respectively). Both vaccines appear to be capable of immunologic priming by immunization in infancy.     

DT5aP-Hib-IPV and MCC vaccines: preterm infants' response to accelerated immunisation.

AIMS: To describe the immune response of preterm infants to combined diphtheria/tetanus/5 component acellular pertussis-Haemophilus influenzae type b inactivated polio vaccine (DT5aP-Hib-IPV) and meningococcal serogroup C conjugate vaccine (MCC) under accelerated schedule. To compare results with term infants immunised with DT5aP-Hib-IPV and with historical data from preterm infants immunised with a DT3 component aP-Hib vaccine. METHODS: Prospective observational study in preterm infants born at <32 weeks gestation with comparison to contemporary cohort of term infants. DT5aP-Hib-IPV and MCC vaccines were given at 2, 3, and 4 months. RESULTS: Fifty preterm infants (mean gestational age 28.5 weeks) completed the study. After three doses of vaccines Hib polysaccharide IgG geometric mean concentration (GMC) was 1.21 microg/ml with 80% > or =0.15 microg/ml; MCC serum bactericidal assay geometric mean titre (GMT) was 1245 with 100% > or =8. All infants achieved protective titres to diphtheria, tetanus, and the three poliovirus types with > or =80% achieving protective rises in IgG against the five pertussis antigens. CONCLUSION: Preterm infants immunised with DT5aP-Hib-IPV and MCC vaccines show IgG responses to Hib and MCC greater than seen historically in both term and preterm infants with a DT3aP-Hib vaccine, and for pertussis antigens and poliovirus type 1 responses similar to that seen in term infants immunised with DT5aP-Hib-IPV. Responses to poliovirus types 2 and 3 are reduced, but all infants achieved protective titres.     

Immunogenicity and reactogenicity of a combined adsorbed tetanus toxoid, low dose diphtheria toxoid, five component acellular pertussis and inactivated polio vaccine in six-year-old children

BACKGROUND: The objective of this study was to assess the immunogenicity and reactogenicity of the combined adsorbed tetanus toxoid, low dose diphtheria toxoid, 5-component acellular pertussis and inactivated polio vaccine (TdcP-IPV) as compared with a pediatric dose diphtheria formulation, combined with adsorbed tetanus toxoid and 3-component acellular pertussis (DTacP), in 6-year-old children who were immunized with 4 doses of diphtheria-tetanus-whole cell cellular pertussis (DTwcP) plus oral polio vaccine (OPV) before 2 years of age, according to the local Spanish vaccination calendar. METHODS: One hundred ninety-four healthy 6-year-old children were randomized to receive 1 dose of TdcP-IPV or 1 dose of DTacP and OPV. RESULTS: One month postvaccination, antidiphtheria and antitetanus titers were > or =0.1 IU/mL in 100% of patients in both study groups. TdcP-IPV reached 100% seroprotection rates against polio types 1, 2 and 3. In OPV recipients, these rates were 100, 100 and 96.8%, respectively. Seropositivity rates for pertussis toxin, filamentous hemagglutinin, pertactin and fimbrial components of the TdcP-IPV vaccine were 97.9, 89.6, 90.6 and 100%. The incidence of local and systemic reactions was 50.5 and 39.2% in the TdcP-IPV group and 59.4 and 38.5% in the DTacP plus OPV group, and no serious adverse events were reported. CONCLUSIONS: TdcP-IPV vaccine was shown to be immunogenic and safe when given as a booster in children 6 years of age who were primed with 4 doses of DTwcP and OPV.     

Seroprevalence of diphtheria and pertussis immunoglobulin G among children with pneumonia in Ji’nan,China

Background

Vaccination is still one of the most important methods to control and prevent childhood infections including diphtheria and pertussis. This study evaluated the level of diphtheria (DT) and pertussis (PT)-related antibodies among children with pneumonia in Ji’nan, China.

Methods

A total of 484 sera of children from 1?day to 13?years of age were collected from 2014 to 2015 in Ji’nan. Children with recent history of pertussis were excluded from this study. Anti-DT and PT IgG concentrations were measured by ELISA (Euroimmun, Lübeck, Germany).

Results

Of the 484 subjects tested, the overall positivity rate of anti-DT IgG (≥0.1?IU/ml) was 48.97%, and the highest positivity rate of anti-DT IgG (68.55%) and proportion with long term protection (23.27%) were observed in children aged 6?m-?<?3 y. For anti-PT IgG, 334 subjects (69.01%) had anti-PT IgG levels below the lower limit of detection (5?IU/ml). Even with detectable anti-PT antibodies, the majority (115/150, 76.67%) of them had antibody levels of 5-?<?40?IU/ml. The highest proportion of subjects with detectable anti-PT IgG (≥5?IU/ml) was observed in children aged <?6?m (44.36%), then the proportion continually decreased to 15.0% at 3 y-?<?6 y (χ²?=?24.05, p?<?0.0001). The highest positivity rate (≥40?IU/ml) was only 8.27% in children aged <?6?m. Subjects with an anti-PT IgG ≥100?IU/ml were observed in all the groups and there were no significant differences in the proportions of subjects with a level?≥?100?IU/ml among these age groups (χ²?=?2.572, p?=?0.4624). A total of 5 subjects had anti-PT IgG ≥100?IU/ml (≥1?years post pertussis vaccination) which was considered to be indicative of a recent pertussis infection.

Conclusions

We demonstrated low antibody levels and protection against pertussis in our study population. The anti-PT IgG maintained a low level throughout all age groups, and even no immune responses were observed after the basic immunization and booster. Our study supported the need to reevaluate the immune response of DTP vaccine which was used in Shandong province after 2010.

     

Safety and immunogenicity of Haemophilus influenzae type b oligosaccharide-CRM197 conjugate vaccine in infants aged 15 to 23 months

A total of 268 infants aged 15 to 23 months received one dose of a vaccine composed of Haemophilus influenzae type b oligosaccharides covalently linked to the nontoxic diphtheria toxin variant CRM197 (HbOC; HibTITER). Side effects associated with vaccination were infrequent, transient, and mild. One month after a single vaccination, the anti-H influenzae type b capsular polysaccharide antibody concentration rose from a geometric mean prevaccination level of 0.20 microgram/mL to 13.77 micrograms/mL. Of these infants, 99% had a postvaccination level greater than or equal to 1.00 microgram/mL, a level associated with long-term protection. The immune response was long-lived: all of the children who were monitored 17 to 27 months after vaccination had concentrations greater than or equal to 1.00 microgram/mL. The anti-H influenzae type b capsular polysaccharide antibody generated was predominantly of the IgG isotype and IgG1 subclass. The immune sera had bactericidal activity in vitro and conferred passive protection in the infant rat meningitis model.     

Antibody persistence in five-year-old children who received a pentavalent combination vaccine in infancy

BACKGROUND: Antibody persistence was studied in 5.5-year-old Swedish children who in infancy completed a vaccine trial of a combined diphtheria toxoid, tetanus toxoid, acellular pertussis, inactivated polio and Haemophilus influenzae type b conjugate vaccine. Three priming doses at ages 2-4-6 months induced higher geometric mean concentrations of antibodies for all antigens than did two doses at 3-5 months, but there were no differences in proportions with protective antibody concentrations. After the booster dose administered at 13 or 12 months of age, respectively, there were no differences in concentrations or proportions between the groups. METHODS: In the present follow-up serum samples from 180 of the 228 vaccinees, 88 from the 4-dose and 92 from the 3-dose group, were 4.5 years later again tested for antibodies. RESULTS: The two groups did not differ significantly in antibody concentrations or proportions with antibodies above protective or other defined levels, with the exception of poliovirus type 3 (P < or = 0.01). In all 89% had > or = 0.01 IU/ml antibodies against diphtheria by enzyme-linked immunosorbent assay and 76% by the Vero cell neutralization test, 93% had > or = 0.01 IU/ml antibodies against tetanus, 96 to 99% had detectable antibodies against the polioviruses and 97% had > or = 0.15 microg/ml H. influenzae type b antibodies. As for pertussis only 44% had detectable antibodies against pertussis toxoid by enzyme-linked immunosorbent assay but 99% by Chinese hamster ovary cell neutralization test, and 94% had detectable antibodies against filamentous hemagglutinin. CONCLUSION: We found the persistence of antibodies satisfactory, with no clinically relevant differences in antibody concentrations demonstrated between children vaccinated according to a three dose or a four dose schedule in infancy.     

Adolescent and adult pertussis: disease burden and prevention

PURPOSE OF REVIEW: According to surveillance data provided by the Centers for Disease Control and Prevention, the rates of pertussis disease in adolescents and adults have been increasing. This is likely due to increased recognition and waning vaccine-induced immunity. RECENT FINDINGS: The presentation of pertussis in adolescents and adults is generally a persistent cough, but more serious complications have been reported. In addition, adolescents and adults often serve as sources of pertussis infection in infants and young children. SUMMARY: Acellular pertussis vaccines combined with diphtheria and tetanus toxoids have proven to be well tolerated, immunogenic and effective in reducing pertussis disease in adolescents and adults. These vaccines are currently being recommended to replace the booster diphtheria and tetanus toxoid vaccines in adolescents. Recommendations for the use of these vaccines in adults are still being formulated.     

Subnormal serum concentrations of IgG2 in children with frequent infections associated with varied patterns of immunologic dysfunction

To characterize more fully the immunologic basis for increased susceptibility to infection in patients with low serum concentrations of IgG2, we identified eight infection-prone children, 1 to 2 years of age, with serum IgG2 concentrations greater than 2 SD below the mean for age and followed their serologic and clinical courses for 1 to 3 years. Two of the eight children became clinically and immunologically normal and may have had transient IgG2 deficiency with an exaggerated developmental delay of this late-maturing subclass. The remaining six subjects had persistently subnormal or low-normal serum IgG2 levels and continued to experience frequent infections. All six of these children responded poorly to Haemophilus influenzae type b (Hib) polysaccharide, and four of six responded poorly to Streptococcus pneumoniae type 3 polysaccharide. Both IgG1 and IgG2-specific antibody responses to these vaccines were abnormal. Three of these six children also responded poorly to tetanus toxoid, an antigen that normally induces a predominant IgG1 response. Although five of these six children produced antibodies in response to Hib polysaccharide protein conjugate vaccine, three of four given Hib oligosaccharide CRM conjugate vaccine required booster doses to respond, a pattern of response characteristic of infants less than 6 months of age. Further, although serum concentrations of IgG1 were normal, peripheral blood mononuclear cells from four of six children tested produced extremely small amounts of IgG1 and IgG3 as well as IgG2. Finally, varied patterns of abnormalities of IgG, IgA, IgM, and IgG4 became apparent in five of the six children with persistently low serum IgG2 values. This study demonstrates that subnormal serum concentrations of IgG2 may be associated with varied patterns of immunologic dysfunction, some of which are evolving and may be responsible for increased susceptibility of these children to infection.     

IgG and IgG subclass specific antibody responses to diphtheria and tetanus toxoids in newborns and infants given DTP immunization

To evaluate immune responses to diphtheria and tetanus toxoids in infants we used enzyme-linked immunosorbent assays to detect total IgG and specific IgG-1, IgG-2, IgG-3, and IgG-4 antibody. One group of infants received a newborn dose and subsequently received the usual three doses of DTP. A second group of infants received only the routine dosage at 2, 4, and 6 months of age. In sera acquired at birth, 6, and 9 months of age, there were no statistically significant differences between the two vaccine groups in IgG antibody responses to diphtheria or tetanus, or in IgG subclass tetanus-specific antibody responses. In individual children, tetanus-specific subclass responses were similar in pattern to that for total IgG tetanus antibody, i.e. each IgG subclass response appeared to be regulated by similar mechanisms in that child, but the regulation differed between children. In contrast to a prior study of pertussis immunity, maternally acquired antibody did not significantly affect immune responses to diphtheria or tetanus toxoid by 9 months of age. There was no discernible tolerance due to early tetanus or diphtheria immunization or to high levels of maternally acquired antibody.     

Immunogenicity of Haemophilus influenzae type b conjugate vaccines in infant rhesus monkeys

Two Haemophilus influenzae type b (Hib) polysaccharide-protein conjugate vaccines were evaluated for immunogenicity in eliciting anti-polyribosyl ribitol phosphate (PRP) antibodies in infant rhesus monkeys. Animals received intramuscular injections of either Hib polysaccharide (PRP)-meningococcal outer membrane protein complex or Hib oligosaccharide-CRM197 (HbOC) conjugate vaccines on d 0, 28, and 56. Because HbOC contains the CRM197 mutant diphtheria toxin from Corynebacterium diphtheriae as its protein carrier, the effect of simultaneous injection of diphtheria toxoid on the immunogenicity of HbOC also was evaluated by dividing monkeys vaccinated with HbOC into three groups: HbOC/saline, HbOC/diphtheria and tetanus toxoids, and HbOC/tetanus toxoid (coadministration of HbOC and other vaccine or placebo injected into the flank muscle of different legs). Infant monkeys vaccinated with the PRP-outer membrane protein complex conjugate responded with anti-PRP antibody after the first dose and showed booster responses after the second and third injections. In contrast, infant monkeys vaccinated with HbOC did not respond after three doses of HbOC/saline or HbOC/tetanus toxoid. However, two of three monkeys given concurrent injections of HbOC and diphtheria and tetanus toxoids did respond. The nonresponder monkey to three doses of HbOC and diphtheria and tetanus toxoids did respond to a subsequent injection with PRP-outer membrane protein complex. Thus, concomitant administration of diphtheria toxoid, a common vaccine for human infants, is necessary to elicit an anti-PRP antibody response to HbOC.(ABSTRACT TRUNCATED AT 250 WORDS)     

The vaccination of children with allergic diseases with reduced doses of adsorbed DT-m anatoxin]

During a remission and drug therapy, 71 children suffering from allergic diseases were vaccinated with DT-M toxoid containing different dose of diphtheria (1, 2.5, 5 LF) and tetanus (1, 2.5, 5 EC) antigens. It has been shown that all the children responded to tetanus antigen by adequate serological tests, whereas as regards diphtheria toxoid, the patients immunized with the least dose of DT-M preparation (1 LF + + 1 EC antigens) produced specific antibodies later and at a lower level. During the postvaccinal period, they also manifested an increase of the content of IgE and exacerbation of the underlying disease in 17.8% of cases. The use of DT-M toxoid with 2.5 LF + EC antigens was shown to hold promise in vaccination of children suffering from allergic diseases.     

Effect of probiotics on vaccine antibody responses in infancy – a randomized placebo-controlled double-blind trial

Probiotics are immunomodulatory and may thus affect vaccine antibody responses. With the accumulating evidence of their health-promoting effects, probiotics are increasingly administered in allergy-prone infants. Therefore, we studied the effect of probiotics on antibody responses to diphtheria, tetanus and Haemophilus influenzae type b (Hib) vaccines in 6-month-old infants participating in a randomized placebo-controlled double-blind allergy-prevention trial. Mothers of unborn children at increased risk for atopy used a combination of four probiotic strains, or a placebo, for 4 wk before delivery. During 6 months from birth, their infants received the same probiotics and galacto-oligosaccharides, or a placebo. The infants were immunized with a DTwP (diphtheria, tetanus and whole cell pertussis) at ages 3, 4, and 5 months, and with a Hib polysaccharide conjugate at 4 months. Serum diphtheria, tetanus, and Hib IgG antibodies were measured at 6 months. In the probiotic group, protective Hib antibody concentrations (>/=1 microg/ml) occurred more frequently, 16 of 32 (50%) vs. six of 29 (21%) (p = 0.020), and the geometric mean (inter-quartile range) Hib IgG concentration tended to be higher 0.75 (0.15-2.71) microg/ml than in the placebo group 0.40 (0.15-0.92) microg/ml (p = 0.064). In these respective groups, diphtheria, 0.38 (0.14-0.78) vs. 0.47 (0.19-1.40) IU/ml (p = 0.449), and tetanus, 1.01(0.47-1.49) vs. 0.81 (0.56-1.39) IU/ml (p = 0.310), IgG titers were comparable. In conclusion, in allergy-prone infants probiotics seem not to impair antibody responses to diphtheria, tetanus, or Hib, but may improve response to Hib immunization.