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PubMedDate not supplied

[A study of the serological response of Sudanese children to three associated immunizations (measles, tetanus, meningococcal A meningitis) (author's transl)].

The authors first emphasize the efficiency and economic value of associated immunizations in developping countries. They report the first data collected in a campaign of immunization with a single injection of an extemporaneous mixture of antimeasles, antitetanus and antimeningococcal meningitis vaccines. This campaign took place in the Republic of Suddan from may 1976 to july 1977 and concerned 87 children. The specifications of each vaccine as well as the procedures of vaccination and serological control are given. The study of serological rates shows: -- a good response for measles with, in Africa, an optimal âge of 6 months and a new injection 6 months later; -- a low and late antibodies rise in tetanus with a good immunological memory giving way to an acute rise under a 2nd injection one year later; -- an immediate increase of the basic low rate of meningococcic antibodies existing in most Suddanese children before the injection. The authors consider the advantage of using also anti C meningococcal vaccine and to add an inactivated poliomyelitic vaccine. They give notice of the good stability in tropical environment of the vaccinal mixture they used.

Bacterial Vaccines↗
PubMed2001

[Anti-HBs titers after a vaccination program in children and adolescents. Should a booster dose be given?].

OBJECTIVES: To determine the efficacy and immunogenicity achieved 6 years after the start of a massive vaccination campaign against hepatitis B in newborn infants and adolescents (12 years). The persistence of anti-hepatitis B virus surface antigen (HBS) levels and the need for a booster dose were also assessed. MATERIALS AND METHODS: From 1993 to 1997 the Engerix vaccine (10 micrograms) and since then the Recombivax vaccine (5 micrograms). The vaccination schedule was the standard of three doses (0, 1, 6). Blood analyses were used for determination of anti-HBs between October of 1998 and May of 2000. RESULTS: We studied 382 cases. Five years after the first dose, 96.1% (73/76) has anti-HBs and in 75% (57/76) levels were above 10UI/L. Six to seven years after vaccination anti-HBs were detected in 94,1 (32/34) of the children and in 70.6% (24/34) of these, levels were above 10UI/L. CONCLUSIONS: A high percentage of children were found to have good levels of anti-HBs 67 years after vaccination. Recent studies show that booster doses are not required because of the immunologic memory that produces the vaccine. The anti-HB protective level (> or = 10UI/l) should not be taken into consideration because this level is only valid when passive immunity with immunoglobulins is applied.

Adolescent↗
PubMedDate not supplied

[Hepatitis B vaccination. Indications of the post-vaccine serologic test and booster doses].

The standard anti-HBV vaccination elicits protective anti-HBs levels (above 10 UI/l) in most people. However, the effective duration of immunologic memory is not well-known. Consequently, the recommendations on the postvaccination follow-up are not uniform: from vaccination with no follow-up blood test (anti-HBs levels) to regular follow-up blood tests for all vaccines. In unresponsive subjects a booster dose has been demonstrated to be effective. However, the optimal procedure for management depending anti-HBs levels has not been well established. Postvaccination antibody testing and regular testing for antibodies is recommended only to high-risk subjects, especially to health care workers and subjects with immunodeficiency. In these cases, the booster dose should be administered in nonresponders, and might include double doses. Unanimous consensus does not exist about to the appropriate timing for booster dose administration.

Adolescent↗
PubMed1998

[Persistence of HB vaccine immune protection and response to hepatitis B booster immunization].

OBJECTIVE: To determine the persistence of immune protection of China-made, plasma-derived HBV vaccine in infants and the time table of booster immunization. METHODS: Serological effect of 7-year follow-up study and antibody response of an experimental study on booster were detected using radioimmunoassay. RESULTS: The protective anti-HBs positive rates of 1,018 children, who were vaccinated according to the regimen of three doses of 10 micrograms HBV vaccine, declined from 75.0% during the first two years to 48.2% at 7 years after the first dosages, however, the positive rates for HBsAg and anti-HBc always fluctuated at low frequency. 144 children aged 6 or 7 years old, who received the HBV vaccine in their infancy and were negative for both HBsAg and anti-HBc before booster, were selected from 1,018 children of the follow-up study and boosted with 1 microgram (intradermally) or 2 micrograms (hypodemically) HBV vaccine. Their anti-HBs GMT and anti-HBs positive rate were 190.6 mIU/ml and 89.6% at one month after booster, significantly higher than 14.7 mIU/ml and 54.9% before booster (P < 0.01), and declined back to 25.3 mIU/ml and 75.5% at 12th month; among 65 children with the anti-HBs negative before booster, 40 of them had the level of anti-HBs > or = 100 mIU/ml one month after booster, suggesting the retention of immunological memory in most of them. CONCLUSIONS: No need for revaccination against hepatitis B at 7th year after the initial immunization due to better persistence of immune protection of the vaccine.

Child↗
PubMed2000

Humoral immune response following hepatitis B vaccine booster dose in children with and without prior immunization.

One hundred and twenty-three children who had received no, incomplete and complete primary hepatitis B vaccination but had negative or very low anti-HBs titer were immunized with a single dose of recombinant hepatitis B vaccine. Blood tests for anti-HBs were obtained at 30 +/- 5 days after the booster immunization. Twelve of 18 (66.7%) children without prior immunization (group 1) seroconverted following the single dose Seroconversion rates in children who had undetectable anti-HBs with incomplete and complete primary immunization (group 2 and 3) were 83.34% and 94.5%, respectively. All children with complete 3- dose vaccination but who had low anti-HBs titer (group 4) also seroconverted. This study confirmed that immunological memory, allowing a protective anamnestic response, lasted at least 8 years in children who had received primary HB immunization with undetectable anti-HBs. Therefore, we conclude that the booster dose after complete vaccination is not necessary in healthy children.

Child, Preschool↗
PubMed2001

Potent antitumor effects of CD154 transduced tumor cells in experimental bladder cancer.

PURPOSE: Current intravesical immunotherapy for bladder cancer with bacillus Calmette-Guerin instillations is standard treatment for patients with high risk superficial tumors but relapses are common. We evaluated the tumor vaccine concept in murine bladder cancer by comparing tumor cell transduction with genes coding for the immunostimulatory molecules CD154, interleukin (IL)-12 and CD80 to design a novel vaccination strategy. MATERIALS AND METHODS: Adenoviral vectors were used to transduce murine bladder cancer MB-49 cells with genes coding for CD154, IL-12 and CD80. Parental or transduced MB-49 cells were injected subcutaneously into syngeneic mice. The effects of transgene expression on tumorigenicity and the generation of protective immunological memory against challenge with parental tumor were studied. RESULTS: All 76 animals injected with parental MB-49 cells had tumors within 8 to 12 days. Tumor cell expression of CD154 combined with IL-12 completely inhibited tumor outgrowth with all 21 mice tumor-free and CD154 transduction alone was almost as effective with 33 of 35 tumor-free. IL-12 production by tumor cells delayed tumor outgrowth and 4 of 10 mice remained tumor-free. Over expression of CD80 had no effect on tumorigenicity. CD154 expressing tumors were rapidly infiltrated with large numbers of CD4+ and CD8+ T cells. Mice vaccinated 4 times with adenoviral CD154 transduced MB-49 cells were completely protected against challenge with parental tumor. Co-injection of CD154 modified cells with parental MB-49 cells retarded tumor growth. CONCLUSIONS: Our experimental results suggest that the potent antitumor effects of CD154 gene transduction should be considered for immunostimulatory gene therapy for bladder cancer.

Animals↗
PubMed2002

[Pneumococcal disease and its prevention. The heptavalent pneumococcal conjugate vaccine].

Pneumococcal disease is a major cause of morbidity, hospitalization and mortality. Two age groups show a greater incidence and severity of the disease: children under the age of 5 years (mainly during the first 2 years of life) and adults aged more than 65 years. The heptavalent pneumococcal conjugate vaccine, which was commercialized in Spain in June 2001, is efficacious in children aged less than 2 years and, unlike the non-conjugate 23-valent vaccine, it induces immunological memory. In Spain the heptavalent vaccine covers 80 % of serotypes causing pneumococcal invasive disease and acute otitis media in children aged 2-59 months. The heptavalent vaccine has been shown to be immunogenic, efficacious and safe. It has proven efficacy in the prevention of invasive disease caused by the seven vaccine serotypes. In addition, it significantly decreases pneumonia and also prevent acute otitis media. The vaccine is preferably indicated in children aged less than 2 years; children aged 2-5 years may also benefit from the vaccine but those in risk groups should be prioritized. Greater knowledge of the epidemiology of pneumococcal disease and the efficiency of this vaccine in Spain will determine whether it should be included in the immunization schedule.

Child↗
PubMed2002

Cancer vaccines, a critical review--Part I.

Cancer vaccines are more properly referred to as 'active specific immunotherapy', and are used to treat cancers rather than to prevent them, at least at present. Vaccines augment already established tumor immunity, are far more specific against the tumor than cytokines, have little or no toxicity, and thus may easily be combined with other types of immunotherapy. They also elicit immunological memory, which may check recurrence of the tumor. Melanoma vaccines have received the most attention thus far. Among the several vaccines in clinical trials are whole cell lysates, such as Melacine, hapten-treated autologous melanoma cells (M-Vax) and irradiated allogeneic cells (CancerVax). Regressions of metastatic nodules have been noted with each preparation. Controlled trials of Melacine indicate prolongation of survival in patients with resected stage IIB disease, particularly those with one or more of the following HLA class I alleles: HLA-A2 or -A28 (-A6802), HLA-B12, -44 or -45, and HLA-C3. A combination of interferon-alpha2b and Melacine appears to enhance the anti-tumor response in advanced (stage IV) disease, and is being tested in a large randomized controlled trial in resected stage III disease. An irradiated autologous colon carcinoma vaccine has improved relapse-free survival in resected stage II disease (Dukes B) in a controlled trial. Second-generation whole cell vaccines include those incorporating genes such as GM-CSF or CD80 (B7-1) to improve immunogenicity, and the use of immunogenic cell membranes such as large multivalent immunogen (LMI). Upregulation of HLA class II molecules and concomitant inhibition of the Ii molecule are also being explored as a strategyfor improved presentation of tumor-associated antigens in vaccines. Complex whole cell-derived vaccines have given clinically superior responses compared to vaccines containing well-defined antigens, such as peptides or gangliosides; however, well-defined vaccines are theoretically more desirable because of their reproducibility.

Animals↗
PubMed2003

Influence of adjuvant hormone therapy and chemotherapy on the immune system analysed in the bone marrow of patients with breast cancer.

PURPOSE: Bone marrow is a special compartment for antitumor immunological memory in patients with breastcancer. Until now, the influence of adjuvant systemic therapy on the immune system has only been investigated in peripheral blood and not in bone marrow. In this study, we analyzed the effect of hormone therapy and chemotherapy on the immune activation status in bone marrow. EXPERIMENTAL DESIGN: In 34 patients with breast cancer, bone marrow was aspirated 24 months after primary surgery and adjuvant systemic therapy. The immune system of these patients was compared with that of patients at the time of primary surgery (n = 90). Three-color flow cytometry was used to identify the number and activation state of T cells, natural killer (NK) cells, monocytes/macrophages, and subsets by means of a panel of monoclonal antibodies. RESULTS: The proportion of all T cells was significantly lower in patients after adjuvant systemic therapy than in patients with primary breast cancer or normal healthy donors. Chemotherapy apparently had a particularly suppressive effect on naïve CD4 T cells and, to a lesser extent, on memory CD4 T cells. Hormone therapy apparently had a significant suppressive effect on both naïve and memory CD8 T cells. The numbers of NK cells (CD56) and of monocytes/macrophages (CD14) recovered rapidly after adjuvant chemotherapy. However, subpopulations with potential antitumor reactivity, such as activated NK and NK T cells, were reduced per long term after chemotherapy. CONCLUSIONS: These findings suggest profound and long-lasting negative effects on the bone marrow immune system by present day adjuvant therapy in breast cancer.

Bone Marrow Cells↗
PubMed2002

Murine Model of Tuberculosis. In vitro and in vivo Study.

Animal models that mimic the whole spectrum of susceptibility and resistance of human populations to tuberculosis would be useful for studying pathogenesis of tuberculosis, mechanisms of the host defense, and for testing prospective prophylactic and therapeutic tuberculosis vaccines and drugs. Inbred mouse strains are broadly and successfully used to model human tuberculosis and study mechanisms of host-mycobacteria interaction. Here we consider numerous aspects of murine models of tuberculosis. We analyze the course of tuberculosis depending on route and dosage of mycobacterial infection, and discuss the conformity of these approaches to the natural route of human infection. The advantage of the mouse model is provided by the availability of hundreds of inbred strains with different genetic background. It allows a genetic analysis of the mouse susceptibility/resistance to tuberculosis. Mouse strains with specific properties such as congenic, recombinant, recombinant inbred, recombinant congenic, mutant and usage of whole genome screening led to mapping loci controlling these traits. Transgenic mouse strains with gene insertion or targeted mutation (knock-out of a gene) are very effective tools for studying the role of specific genes controlling the anti-tuberculosis immunity. Mice with knock-out genes for cytokines, chemokines, cell subpopulations, cell receptors, and enzymes are broadly used to identify the mechanisms of tuberculosis control. In this review we examine a mouse model for anti-tuberculosis vaccine and drug testing. In addition, we present some important phenomena of tuberculosis immunity - latent tuberculosis/reactivation and immunological memory to tuberculosis.

Animals↗
PubMed2003

[Chemokines and chemokine receptors in multiple sclerosis].

Findings of chemokines and chemokine receptors in multiple sclerosis(MS) are reviewed. MS is a T-helper type 1 (Th1) dominant condition, and Th1-associated chemokine receptors(CCR5 and CXCR3) on CD4- and CD8-positive T cells and their ligands are upregulated in the CNS of the patients with active disease. Meanwhile, Th2-associated chemokine receptors(CCR3 and CCR4) on CD4- and CD8-positive T cells are suppressed during relapse. Their expressions are useful immunological measures of disease activity, clinical subtypes and therapy. CCR7 and the ligands are expressed in the CNS of MS and may be important for the recruitment of immune cells committed to immunological memory and antigen presentation.

Animals↗
PubMed2003

Conjugate vaccines--a breakthrough in vaccine development.

The encapsulated bacteria Streptococcus pneumoniae (the pneumococcus), Neisseria meningitidis (the meningococcus) and Haemophilus influenzae type b (Hib) are the main causes of purulent meningitis, the peak incidence of which is seen in the first two years of life. The polysaccharide capsule of these bacteria is an essential virulence determinant, and antibodies to it are protective, suggesting that a polysaccharide vaccine could prevent these diseases. The young child is, however, unable to respond with antibody production to these polysaccharides, making such vaccines useless in infancy. Conjugation of the polysaccharide to a protein carrier has proven a way to solve the problem. Immunization of infants with such a Hib conjugate vaccine was shown in 1987 to result in the desired antibody production and protection from Hib meningitis and bacteremia. The Hib vaccine is now a part of national infant immunization programs in large parts of Europe, the Americas and Australia, and has resulted in the virtual disappearance of Hib disease from these areas. A group C meningococcal and 7-valent pneumococcal vaccine, available since 2000, are likewise proving highly effective in preventing bacteremic disease. Further advantages of the conjugate vaccines are their ability to elicit immunologic memory and to reduce asymptomatic carriage of the bacteria, resulting in marked herd immunity. This paper was delivered as a lecture in January 2003 in Bangkok on the occasion of the Prince Mahidol Award for a life's work in the field of vaccinology.

Bacterial Vaccines↗
PubMed1992

Immunogenic properties of multiple antigen peptide systems containing defined T and B epitopes.

Immunization with chemically defined synthetic polymers, multiple Ag peptide (MAP) systems, containing T and B epitopes of the circumsporozoite protein of P. berghei induce high levels of circulating antibodies that are detectable several months after boosting. The anti-MAP secondary antibody response is characterized by an increase in the levels of circulating IgG and a concomitant decrease in the IgM levels. In vitro and in vivo experiments indicated that Th epitopes included in the MAP are recognized by T cells induced after immunization with the native protein and, also, that MAP-induced T cells can recognize the native protein. In addition to high levels of anti-B epitope antibodies, MAP immunization also induces antibodies against the T epitope. This anti-T epitope immune response does not affect the generation of the anti-B epitope antibodies. Immunization of different strains of mice revealed that the antibody response is consistent with the genetically restricted pattern of recognition of the T epitope. There are, however, significant differences in the levels of antibody responses observed among responder strains. The findings of this study indicate that MAP are potent immunogens capable of inducing immunologic memory and are, thus, good candidates for the development of subunit vaccines designed to induce high levels of circulating antibodies.

Animals↗
PubMed1992

Conserved T and B cell epitopes on the M protein of group A streptococci. Induction of bactericidal antibodies.

To identify conserved T and B cell epitopes on the M protein of group A beta-hemolytic streptococci, overlapping synthetic peptides that span the conserved carboxyl-terminal segment of the M-5 protein were constructed and used to immunize a panel of H-2 congenic mice. Proliferative T cell epitopes were identified and, in many cases, mice immunized with these peptides produced high titer antibodies to the same peptides indicating that these proliferative epitopes could also stimulate Th cells. Peptide-specific T cells and antisera were tested for their reactivity with porcine myosin, tropomyosin, human heart myosin synthetic peptides, and extracts of human pericardial and atrial heart tissue. Although there was minimal response of M peptide-specific T cells to any of these Ag, certain M peptide-specific antisera reacted to immunoblotted porcine myosin and to an immunoblotted extract of human atrial heart tissue. However, two conserved peptides, LRRDLDASREAKKQVEKALE and KLTEKEKAELQAKLEAEAKA, stimulated peptide-specific antibodies in B10.BR and B10.D2 mice respectively, which reacted minimally if at all with human atrial heart tissue extract. Furthermore, antisera to the former peptide, in a bactericidal assay involving human monocytes, could mediate killing of streptococci (82% of bacteria). Although this level of killing is less than that produced by antisera to the highly polymorphic type-specific aminoterminus (up to 100% killing), it provides evidence that conserved epitopes can be the targets of bactericidal antibodies. These conserved epitopes may be useful in a vaccine because they also stimulate T cells, thus allowing development of immunologic memory and natural boosting of an immune response after natural exposure.

Amino Acid Sequence↗
PubMed2003

[Immunology against meningitis C. Review of the literature].

The author reviews current scientific knowledge about immunologic changes regarding Meningitis C. This bears with it the use of vaccinations which have to be more effective and safe all the time. In order to defend this, the author presents studies based on clinical trials, whose corresponding analysis and interpretation were carried out and these studies are processed together with experiences accumulated over the years in other countries, such as the United States. The author includes significant research studies to justify the use of a vaccine which is conjugated out of Meningitis C (MenC) as opposed to the previously authorized polysaccharide composed of Meningitis A+C (MenPS). The author analyses factors such as offered immunity, expressed in geometric concentrations at the middle IgG range and the active bacterial listings, the length of immunologic memory and its simultaneous use with other vaccines. The author demonstrates the effectiveness presented by the MenC vaccine when compared to the MenPS vaccine.

Adolescent↗
PubMed1992

In vivo cytotoxic T lymphocyte induction with soluble proteins administered in liposomes.

The in vivo induction of a CTL response usually requires that Ag be endogenously synthesized so that appropriate processing can occur. In most of the few examples where successful CTL induction was reported with proteins and peptides, unacceptable adjuvants or means of Ag formulation were used. In the present report, liposomes were used to incorporate the soluble proteins OVA and beta-galactosidase. This simple and convenient to use approach, which requires minimal amounts of Ag, results in priming for a CD8+ CTL response and the establishment of immunologic memory. The liposome approach may not only prove a convenient means of inducing CTL responses in vivo but may also be useful to study the mechanisms of Ag processing.

Animals↗
PubMed1992

A diphasic immune response against bacteria in the American cockroach.

The adult cockroach generates an adaptive humoral immune response exhibiting specificity and immunological memory when immunized with soluble proteins. In contrast, the response induced by bacteria in holometabolous insects is non-specific and short term, generally losing activity after 72 hr. We have found that the roach generates a diphasic response when injected with bacteria, displaying an acute non-specific phase initially, which is then superseded by a second response that is relatively long term and specific. Animals were immunized with either killed Pseudomonas aeruginosa or pyrogen-free Burns-Tracey saline (BTS) and challenged at various times post-immunization (p.i.) with a lethal dose of viable P. aeruginosa. The induction of immunity was measured by monitoring the percentage of survivors after challenge. Immunization with killed P. aeruginosa induced significant (P less than 0.05) protection against challenge as compared with BTS controls. The response was elicited by Day 1 p.i. and did not begin to decline until after Day 14 p.i. The specificity of the response was tested by immunizing animals with either killed Serratia marcescens, Enterobacter cloacae, Streptococcus lactis or Micrococcus lysodeikticus, and then challenging them with live P. aeruginosa. Significant protection against P. aeruginosa challenge was induced by any of the bacteria within the first 3 days p.i. However, by Day 4 the response began to show specificity. Immunization with P. aeruginosa induced significantly more protection than immunization with any one of the other organisms, and only the Gram-negative organisms (P. aeruginosa, E. cloacae and S. marcescens) induced any protection relative to controls.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗