Immunization against hepatitis A in the first year of life: priming despite the presence of maternal antibody

Dagan, Ron; Amir, Jacob; Mijalovsky, Analia; Kalmanovitch, Irena; Bar-Yochai, Avihu; Thoelen, S; Safary, Assad; Ashkenazi, Shai

doi:10.1097/00006454-200011000-00004

Cited by 129 publications

(71 citation statements)

References 18 publications

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“…The B-cell immune responses of infants were inhibited in the presence of MatAbs until the MatAb titer had fallen below a specific threshold. However, the infants' responses showed that they had been primed by the initial vaccination despite the interference, indicating unaffected T-cell priming (10). Based on our results, it is conceivable that in the presence of the high MatAb levels, the Pnc1-TT-immunized offspring might respond to a booster dose of Pnc1-TT when the MatAbs have fallen below a critical threshold.…”

Section: Discussionmentioning

confidence: 68%

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Protective Levels of Polysaccharide-Specific Maternal Antibodies May Enhance the Immune Response Elicited by Pneumococcal Conjugates in Neonatal and Infant Mice

et al. 2005

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Maternal antibodies (MatAbs) may protect the offspring against infections but may also interfere with their immune responses to vaccination. We have previously shown that maternal immunization with pneumococcal polysaccharides (PPS) conjugated to tetanus protein (Pnc-TT) protected the offspring against infections caused by three important pediatric serotypes. To study the influence of MatAb on the immune response to Pnc-TT early in life, adult female mice were immunized twice with Pnc-TT of serotype 1 (Pnc1-TT), and their offspring received Pnc1-TT subcutaneously three times at 3-week intervals starting at 1 week (neonatal) or 3 weeks (infant) of age. High levels of PPS-1-specific MatAb (>3 log) in offspring of Pnc1-TT-immunized dams completely inhibited their anti-PPS-1 response elicited by Pnc1-TT. In contrast, low or moderate (ϳ1 to 2 log) levels of MatAb did not interfere with and even enhanced the immune response of the offspring, and a booster response to a second Pnc1-TT dose was observed. Carrier-specific MatAbs had little effect on the response of offspring to the conjugate. All Pnc1-TT-immunized offspring were protected against pneumococcal bacteremia and had reduced lung infection. These results demonstrate that in the presence of MatAb, Pnc1-TT may elicit a protective PPS-1-specific antibody response and prime for PPS-1-specific memory in young offspring. Importantly, low or moderate levels of PPS-1-specific MatAb not only provided protection against pneumococcal infections but also enhanced the immune response elicited by Pnc1-TT in neonatal and infant mice. This murine model will be used to develop novel strategies combining maternal and neonatal immunization to protect against infections caused by encapsulated bacteria in early life.

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Section: Discussionmentioning

confidence: 68%

“…Student's t test and nonparametric test (Mann-Whitney) were used to compare log antibody titers and numbers of CFU (log 10 …”

Section: Methodsmentioning

confidence: 99%

Protective Levels of Polysaccharide-Specific Maternal Antibodies May Enhance the Immune Response Elicited by Pneumococcal Conjugates in Neonatal and Infant Mice

et al. 2005

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“…A study conducted in India presented data suggesting that children should be immunized against HAV by 10 months of age, when the maternal antibodies disappear (Chadha et al 1999). Pre-existing maternal antibodies do interfere with the immune response to hepatitis A vaccine (Dagan et al 2000, Letson et al 2004, although some studies have shown that infants born to anti-HAV-positive mothers develop anamnestic responses with a booster dose of hepatitis A vaccine (Fiore et al 2003, Letson et al 2004.…”

Section: Discussionmentioning

confidence: 99%

Early infection and asymptomatic spread of hepatitis A virus in a public child care center in Rio de Janeiro, Brazil: should attending children under two years of age be vaccinated?

Morais

Paula

Arantes³

et al. 2006

Mem. Inst. Oswaldo Cruz

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A cross-sectional study was conducted in order to identify hepatitis A virus (HAV) serological markers in 418 individuals (mean age, 16.4 years; range, 1 month-80 respectively, in 89.5% (374/418) and 10.5% (44/418) IA and IB in 93.3% (28/30) Hepatitis A virus (HAV) is a hepatotropic virus and a member of the Hepatovirus genus within the Picornaviridae family (Minor 1991). The virus is responsible for the majority of the acute hepatitis cases in Brazil (Gaspar et al. 1996), and infection symptoms are age-related. Among HAV-infected individuals, children under 6 years old are typically asymptomatic, whereas older children and adults develop jaundice or present dark urine. The prevalence of HAV infection is closely correlated with the level of environmental sanitation and with prevailing socioeconomic and hygiene conditions. The incidence of HAV is higher in developing countries, although the pattern of HAV endemicity in several of these countries has dropped from high to intermediary due to improvements in sanitation conditions in recent decades (Tapia-Conyer et al. 1999, Tanaka 2000. As a consequence, increasing proportions of those populations have had no contact with HAV and are therefore more susceptible to infection. In Brazil, hepatitis A is still considered an endemic disease, although data collected in the state of Rio de Janeiro indicate that a shift in the hepatitis A epidemiological pattern has taken place (Santos et al. 2002, Villar et al. 2002. of the individuals tested. Acute HAV infection in children was independently correlated with crawling (p < 0.05). In 56.8% (25/44) of the IgM anti-HAV-positive individuals and in 33.3% (5/15) of the IgM anti-HAV-negative individuals presenting clinical symptoms, HAV RNA was detected. Phylogenetic analysis revealed co-circulation of subgenotypesThe virus is usually transmitted via the fecal-oral route, either through person-to-person contact or through in- (Gehlbach et al. 1973, Williams et al. 1975. Results of some studies have suggested that HAV is transmitted mainly by children with either asymptomatic or subclinical infection. Lack of proper hygiene facilitates HAV transmission from such children to their relatives and friends, as well as to child care center staff members (Castelli et al. 1999, Poovorawan et al. 2005.The HAV strains have been classified into six genotypes (I to VI), based on nucleotide sequences of the VP1/2A junction region (Robertson et al. 1992. Prevalent human strains fall into genotypes I or III, each of which are divided into subtypes A and B. In Brazil, co-circulation of subgenotypes IA and IB have been found in Rio de Janeiro , Villar et al. 2004. Circulation of subgenotype IA has also been detected in other regions of Brazil (de Paula et al. 2004).Since it was first reported that HAV was able to propagate in cell culture (Provost et al. 1979), there have been many attempts to develop an HAV vaccine. In the United States and some other countries, safe and effective formalin-inactivated HAV vaccines against hepatitis A have ...

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“…No obstante, el 85 a 95% de los adultos inmunocompetentes seronegativos (75 a 80% en personas sobre 40 años) que reciben la primera dosis de vacuna, presentan anticuerpos anti VHA en el plazo de 10 a 14 días, sobre los niveles protectores 5-8 ; a los 28 días cerca del 100% alcanzó títulos protectores, y en una concentración superior a la primera determinación [5][6][7][8] . Esta respuesta es similar en niños de toda edad [9][10][11][12] , con títulos algo menores si la vacuna es administrada en el primer año de vida [13][14][15][16][17][18] . En estudios comparativos se ha observado mayores títulos de anticuerpos otorgados por algunas vacunas que otras, lo que no parece tener mayor relevancia en el corto ni a largo plazo pues se trata de diferencia entre concentraciones que son siempre 10 a 100 veces superiores a las protectoras.…”

Section: Inmunogenicidadunclassified

“…Sin embargo, estudios de inmunogenicidad posteriores efectuados en lactantes en su segundo año de vida con Avaxim 80® UI y Havrix® 720 UE 34,35 , comprobaron que ya a esa edad la inmunidad materna no interfiere sobre la frecuencia ni la intensidad de la respuesta inmune específica y, considerando estos nuevos antecedentes, se autorizó la licencia en Europa y algunos países latinoamericanos, a partir de los 12 meses de edad. Bajo un año de vida, la transferencia pasiva de anticuerpos anti VHA sí interfirió parcialmente esta respuesta a vacuna Havrix® 720 UE 15 , Havrix® 360 UE 13,14 y Avaxim® 80 UI [16][17][18] observándose menores títulos de anticuerpos anti VHA en hijos de mujeres seropositivas que en hijos de mujeres seronegativas, aunque la seropositividad de la madre no impidió la estimulación inmune y priming en el lactante por el antígeno vaccinal 15,16 . una notable y rápida reducción de la incidencia de la enfermedad en 3 años, no sólo en las cohortes vacunadas sino que a toda edad 36,37 .…”

Section: Inmunogenicidadunclassified

Vacuna anti hepatitis A

2003

Rev. chil. infectol.

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Hepatitis A vaccineInactivated hepatitis A vaccine is an valuable preventive prophylactic tool because of its high immunogenicity, capacity to induce immunological memory and high efficacy and safety profile. It may be utilized since 12 month age with excellent seroconversion. The several available hepatitis A vaccines are interchangeable facilitating its use in a public health setting. The best way to benefit countries like Chile with intermediate endemicity is to implement a cohort vaccination program and to use it in the control of circumscribed outbreaks. Moreover it represents an alternative strategy to human normal immunoglobulin for immunoprophylaxis in close contact at home and enclosed institutions. In this article we present an exhaustive review of published experiences that support these asseverations.Key words: Hepatitis A, Vaccines; Inactivated; Immunogenicity; Efficacy; Safety; Public health; Expanded Program on Immunization IntroducciónLa infección causada por virus de hepatitis A (VHA) es endémica en nuestro país con ciclos de mayor incidencia como se aprecia en un informe del Ministerio de Salud de Chile publicado en este mismo número 1 . Las posibilidades de control y eliminación del VHA son reales ya que el reservorio es exclusivamente humano, no se ha descrito la infección crónica y, si bien se han identificado 4 genotipos a lo largo del mundo, sólo se conoce un serotipo, de distribución universal, que está determinado por epítopes en las proteínas de superficie del virus, posiblemente VP1 y VP3, sin conocerse con precisión contra qué estructura se dirigen los anticuerpos neutralizantes 2 . En buenas cuentas el individuo infectado una vez no se reinfecta. Ésta es la premisa para diseñar vacunas y anunciar el control de la enfermedad, en la medida que las poblaciones sean inmunizadas artificialmente.Este artículo presenta una actualización sobre las vacunas anti VHA preparadas con el virus inactivado, sus propiedades inmunológicas, y el impacto clínico-epidemiológico de su aplicación. No se abordan los antecedentes relativos a vacunas atenuadas cuya experiencia y documentación científica se han centrado fundamentalmente en China.

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Immunization against hepatitis A in the first year of life: priming despite the presence of maternal antibody

Abstract: Our results suggest that the initially seropositive infants were primed despite maternal antibody interference. The hepatitis A vaccine was well-tolerated in this population of young infants.

Cited by 129 publications

References 18 publications

Protective Levels of Polysaccharide-Specific Maternal Antibodies May Enhance the Immune Response Elicited by Pneumococcal Conjugates in Neonatal and Infant Mice

Protective Levels of Polysaccharide-Specific Maternal Antibodies May Enhance the Immune Response Elicited by Pneumococcal Conjugates in Neonatal and Infant Mice

Early infection and asymptomatic spread of hepatitis A virus in a public child care center in Rio de Janeiro, Brazil: should attending children under two years of age be vaccinated?

Vacuna anti hepatitis A

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