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Muri L, Schubart A, Thorburn C, Zamurovic N, Holbro T, Kammüller M, Pluschke G, Ispasanie E. Inhibition of the different complement pathways has varying impacts on the serum bactericidal activity and opsonophagocytosis against Haemophilus influenzae type b. Front Immunol 2022; 13:1020580. [PMID: 36578495 PMCID: PMC9791579 DOI: 10.3389/fimmu.2022.1020580] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2022] [Accepted: 10/25/2022] [Indexed: 12/14/2022] Open
Abstract
Defense against Haemophilus influenzae type b (Hib) is dependent on antibodies and complement, which mediate both serum bactericidal activity (SBA) and opsonophagocytosis. Here we evaluated the influence of capsule-specific antibodies and complement inhibitors targeting the central component C3, the alternative pathway (AP; fB, fD), the lectin pathway (LP; MASP-2) and the terminal pathway (C5) on both effector functions. Findings may be relevant for the treatment of certain diseases caused by dysregulation of the complement system, where inhibitors of complement factors C3 or C5 are used. Inhibitors against other complement components are being evaluated as potential alternative treatment options that may carry a reduced risk of infection by encapsulated bacteria. Serum and reconstituted blood of healthy adults were tested for bactericidal activity before and after vaccination with the Hib capsule-conjugate vaccine ActHIB. Most sera had bactericidal activity prior to vaccination, but vaccination significantly enhanced SBA titers. Independently of the vaccination status, both C3 and C5 inhibition abrogated SBA, whereas inhibition of the LP had no effect. AP inhibition had a major inhibitory effect on SBA of pre- vaccination serum, but vaccination mitigated this inhibition for all disease isolates tested. Despite this, SBA-mediated killing of some Hib isolates remained retarded. Even for the most serum-resistant isolate, SBA was the dominating defense mechanism in reconstituted whole blood, as addition of blood cells to the serum did not enhance bacterial killing. Limited Fc receptor-mediated opsonophagocytosis was unmasked when bacterial killing by the membrane attack complex was blocked. In the presence of C3 or C5 inhibitors, addition of post-vaccination, but not of pre-vaccination serum to the blood cells triggered opsonophagocytosis, leading to suppression of bacterial multiplication. Taken together, our data indicate that for host defense against Hib, killing by SBA is more efficient than by blood cell opsonophagocytosis. However, additional defense mechanisms, such as bacterial clearance by spleen and liver, may play an important role in preventing Hib-mediated sepsis, in particular for Hib isolates with increased serum-resistance. Results indicate potentially improved safety profile of AP inhibitors over C3 and C5 inhibitors as alternative therapeutic agents in patients with increased susceptibility to Hib infection.
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Affiliation(s)
- Lukas Muri
- Molecular Immunology Unit, Swiss Tropical and Public Health Institute, Basel, Switzerland,University of Basel, Basel, Switzerland
| | - Anna Schubart
- Department Autoimmunity, Transplantation and Inflammation, Novartis Institutes for Biomedical Research, Basel, Switzerland
| | | | - Natasa Zamurovic
- Translational Medicine-Preclinical Safety, Novartis Institutes for Biomedical Research, Basel, Switzerland
| | - Thomas Holbro
- Global Drug Development, Novartis Pharma AG, Basel, Switzerland
| | - Michael Kammüller
- Translational Medicine-Preclinical Safety, Novartis Institutes for Biomedical Research, Basel, Switzerland
| | - Gerd Pluschke
- Molecular Immunology Unit, Swiss Tropical and Public Health Institute, Basel, Switzerland,University of Basel, Basel, Switzerland,*Correspondence: Gerd Pluschke,
| | - Emma Ispasanie
- Molecular Immunology Unit, Swiss Tropical and Public Health Institute, Basel, Switzerland,University of Basel, Basel, Switzerland
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Antibody Binding and Complement-Mediated Killing of Invasive Haemophilus influenzae Isolates from Spain, Portugal, and the Netherlands. Infect Immun 2020; 88:IAI.00454-20. [PMID: 32719154 DOI: 10.1128/iai.00454-20] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2020] [Accepted: 07/22/2020] [Indexed: 02/06/2023] Open
Abstract
Haemophilus influenzae is a Gram-negative bacterium that can be classified into typeable (types a through f) and nontypeable (NTHi) groups. This opportunistic pathogen asymptomatically colonizes the mucosal epithelium of the upper respiratory tract, from where it spreads to other neighboring regions, potentially leading to disease. Infection with NTHi can cause otitis media, sinusitis, conjunctivitis, exacerbations of chronic obstructive pulmonary disease, and pneumonia, but it is increasingly causing invasive disease, including bacteremia and meningitis. Invasive NTHi strains are more resistant to complement-mediated killing. However, the mechanisms of complement resistance have never been studied in large numbers of invasive NTHi strains. In this study, we determined the relationship between binding of IgG or IgM and the bacterial survival in normal human serum for 267 invasive H. influenzae strains from Spain, Portugal, and the Netherlands, of which the majority (200 [75%]) were NTHi. NTHi bacteria opsonized with high levels of IgM had the lowest survival in human serum. IgM binding to the bacterial surface, but not IgG binding, was shown to be associated with complement-mediated killing of NTHi strains. We conclude that evasion of IgM binding by NTHi strains increases survival in blood, thereby potentially contributing to their ability to cause severe invasive diseases.
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Riesbeck K. Complement evasion by the human respiratory tract pathogens Haemophilus influenzae and Moraxella catarrhalis. FEBS Lett 2020; 594:2586-2597. [PMID: 32053211 DOI: 10.1002/1873-3468.13758] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2019] [Revised: 01/26/2020] [Accepted: 02/09/2020] [Indexed: 12/14/2022]
Abstract
All infective bacterial species need to conquer the innate immune system in order to colonize and survive in their hosts. The human respiratory pathogens Haemophilus influenzae and Moraxella catarrhalis are no exceptions and have developed sophisticated mechanisms to evade complement-mediated killing. Both bacterial species carry lipooligosaccharides preventing complement attacks and attract and utilize host complement regulators C4b binding protein and factor H to inhibit the classical and alternative pathways of complement activation, respectively. In addition, the regulator of the terminal pathway of complement activation, vitronectin, is hijacked by both bacteria. An array of different outer membrane proteins (OMP) in H. influenzae and M. catarrhalis simultaneously binds complement regulators, but also plasminogen. Several of the bacterial complement-binding proteins are important adhesins and contain highly conserved regions for interactions with the host. Thus, some of the OMP are viable targets for new therapeutics, including vaccines aimed at preventing respiratory tract diseases such as otitis media in children and exacerbations in patients suffering from chronic obstructive pulmonary disease.
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Affiliation(s)
- Kristian Riesbeck
- Clinical Microbiology, Department of Translational Medicine, Faculty of Medicine, Lund University, Malmö, Sweden
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Albrecht T, Poss K, Issaranggoon Na Ayuthaya S, Triden L, Schleiss KL, Schleiss MR. Case report of congenital asplenia presenting with Haemophilus influenzae type a (Hia) sepsis: an emerging pediatric infection in Minnesota. BMC Infect Dis 2019; 19:947. [PMID: 31703560 PMCID: PMC6842177 DOI: 10.1186/s12879-019-4572-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2019] [Accepted: 10/16/2019] [Indexed: 01/26/2023] Open
Abstract
Background In the pre-vaccine era, invasive disease with Haemophilus influenzae, type b (Hib) commonly presented with osteoarticular involvement. Haemophilus influenzae, type a (Hia) sepsis is a rare but emerging problem in recent years. Here, we report a case of sepsis with concomitant osteoarthritis due to Hia that was the presenting infectious disease manifestation of isolated asplenia in a young child. This unique observation adds to our understanding of sepsis and asplenia in children. Case presentation A five-year-old girl developed acute Hia bacteremia and sepsis. The patient developed arthritis shortly after onset of septic shock. Arthrocentesis was culture-negative, but given the difficulty differentiating between septic and reactive arthritis, prolonged antibiotic administration was provided for presumed osteoarticular infection, and the patient had an uneventful recovery. The finding of Howell-Jolly bodies on blood smear at the time of presentation prompted an evaluation that revealed isolated congenital asplenia. Evaluation for known genetic causes of asplenia was unrevealing. Investigation by the Minnesota Department of Health revealed an emergence of Hia infections over the past 5 years, particularly in children with an American Indian background. Conclusions Hia is an important pathogen in the differential diagnosis of invasive bacterial infections in children and shares overlap in clinical presentation and pathogenesis with Hib. Invasive Hia disease can be a presenting manifestation of asplenia in children. Hia is an emerging pathogen in American Indian children.
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Affiliation(s)
- Tiffany Albrecht
- Department of Pediatrics, University of Minnesota Masonic Children's Hospital, 2450 Riverside Ave, Minneapolis, MN, 55454, USA
| | - Kristina Poss
- University of Minnesota Medical School, 420 Delaware Street SE, Minneapolis, MN, 55455, USA.,Present address: Department of Pediatrics, Lincoln Medical Center, 234 E 149th Street, The Bronx, NY, 10451, USA
| | - Satja Issaranggoon Na Ayuthaya
- Department of Pediatrics, University of Minnesota Masonic Children's Hospital, 2450 Riverside Ave, Minneapolis, MN, 55454, USA.,Present address: Children's National Medical Center, 111 Michigan Ave NW, Washington, DC, 20010, USA
| | - Lori Triden
- Minnesota Department of Health, Infectious Diseases, Epidemiology and Control Division, 625 Robert Street N, Saint Paul, MN, 55155, USA
| | - Katherine L Schleiss
- Minnesota Department of Health, Infectious Diseases, Epidemiology and Control Division, 625 Robert Street N, Saint Paul, MN, 55155, USA
| | - Mark R Schleiss
- Department of Pediatrics, University of Minnesota Masonic Children's Hospital, 2450 Riverside Ave, Minneapolis, MN, 55454, USA.
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Kingella kingae Surface Polysaccharides Promote Resistance to Human Serum and Virulence in a Juvenile Rat Model. Infect Immun 2018; 86:IAI.00100-18. [PMID: 29581191 DOI: 10.1128/iai.00100-18] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2018] [Accepted: 03/21/2018] [Indexed: 12/13/2022] Open
Abstract
Kingella kingae is a Gram-negative coccobacillus that is increasingly being recognized as an important cause of invasive disease in young children. The pathogenesis of K. kingae disease begins with colonization of the oropharynx, followed by invasion of the bloodstream, survival in the intravascular space, and dissemination to distant sites. Recent studies have revealed that K. kingae produces a number of surface factors that may contribute to the pathogenic process, including a polysaccharide capsule and an exopolysaccharide. In this study, we observed that K. kingae was highly resistant to the bactericidal effects of human serum complement. Using mutant strains deficient in expression of capsule, exopolysaccharide, or both in assays with human serum, we found that elimination of both capsule and exopolysaccharide was required for efficient binding of IgG, IgM, C4b, and C3b to the bacterial surface and for complement-mediated killing. Abrogation of the classical complement pathway using EGTA-treated human serum restored survival to wild-type levels by the mutant lacking both capsule and exopolysaccharide, demonstrating that capsule and exopolysaccharide promote resistance to the classical complement pathway. Consistent with these results, loss of both capsule and exopolysaccharide eliminated invasive disease in juvenile rats with an intact complement system but not in rats lacking complement. Based on these observations, we conclude that the capsule and the exopolysaccharide have important redundant roles in promoting survival of K. kingae in human serum. Each of these surface factors is sufficient by itself to fully prevent serum opsonin deposition and complement-mediated killing of K. kingae, ultimately facilitating intravascular survival and promoting K. kingae invasive disease.
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Townsend K, Ladhani SN, Findlow H, Borrow R. Evaluation and validation of a serum bactericidal antibody assay for Haemophilus influenzae type b and the threshold of protection. Vaccine 2014; 32:5650-6. [PMID: 25138290 DOI: 10.1016/j.vaccine.2014.08.010] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2014] [Revised: 07/10/2014] [Accepted: 08/06/2014] [Indexed: 11/30/2022]
Abstract
Prior to routine immunisation, Haemophilus influenzae serotype b (Hib) was a major cause of serious bacterial infections, particularly in young children. In the United Kingdom, introduction of the Hib conjugate vaccine into the national childhood immunisation schedule has led to a sustained decline in invasive Hib disease across all age-groups. Evaluation of the immune response to Hib conjugate vaccines involves measurement of serum IgG antibodies against the capsular polyribosyl-ribitol-phosphate (PRP) polysaccharide by enzyme-linked immunosorbent assay (ELISA), with accepted short-term and long-term protective thresholds of ≥0.15μg/mL and ≥1.0μg/mL, respectively. These levels were derived by passive immunisation or immunisation with pure polysaccharide, and their relevance for protection following immunisation with conjugate vaccines remains unclear. This study aimed to modify and optimise a serum bactericidal antibody (SBA) assay to evaluate the functional activity of Hib antibodies generated following Hib conjugate vaccination. Validation of the Hib SBA assay was deemed acceptable for all assay parameters tested. A strong correlation between anti-PRP IgG concentrations and SBA titres was observed in vaccinated adults (r=0.81), as well as infants after primary immunisation at 2, 3, and 4 months (r=0.635) and after the 12-month booster (r=0.746). The assay identified some children with high anti-PRP IgG but low SBA activity and vice versa. The predictive protective SBA titre corresponding to a post-booster anti-PRP IgG of 1.0μg/mL was 8. Thus, the optimised Hib SBA assay was specific and reproducible and correlated with anti-PRP IgG. Such assays may have a role in evaluating immune responses to conjugate vaccines in addition to measuring capsular antibodies.
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Affiliation(s)
- Kelly Townsend
- Vaccine Evaluation Unit, Public Health England, Clinical Sciences Building, Manchester Royal Infirmary, Manchester, UK
| | - Shamez N Ladhani
- Immunisation, Hepatitis and Blood Safety Department, Centre for Infectious Disease Surveillance and Control, Public Health England, Colindale, London, UK.
| | - Helen Findlow
- Vaccine Evaluation Unit, Public Health England, Clinical Sciences Building, Manchester Royal Infirmary, Manchester, UK
| | - Ray Borrow
- Vaccine Evaluation Unit, Public Health England, Clinical Sciences Building, Manchester Royal Infirmary, Manchester, UK; Inflammation Sciences Research Group, University of Manchester, School of Translational Medicine, Stopford Building, Manchester, UK
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Ladhani SN. Two decades of experience with the Haemophilus influenzae serotype b conjugate vaccine in the United Kingdom. Clin Ther 2012; 34:385-99. [PMID: 22244051 DOI: 10.1016/j.clinthera.2011.11.027] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2011] [Revised: 11/16/2011] [Accepted: 11/23/2011] [Indexed: 11/30/2022]
Abstract
BACKGROUND The Haemophilus influenzae serotype b (Hib) conjugate vaccine was introduced into the UK national childhood immunization program in 1992 after clinical trials reported the vaccine to be highly immunogenic in infants as young as two months of age. OBJECTIVE The goal of this study was to describe and comment on the impact of routine Hib immunization on the epidemiology of invasive Hib disease in the United Kingdom. In addition, the development of Hib polysaccharide and conjugate vaccines was reviewed. METHODS A literature search was conducted of PubMed for invasive Hib disease epidemiology in the United Kingdom. The UK Health Protection Agency Web site was also searched for relevant publications. RESULTS The incidence of invasive Hib incidence in children aged <5 years fell from 21/100,000 to 44/100,000 in the prevaccine era to 0.63/100,000 in 1998, with an estimated vaccine failure rate of 2.2/100,000 vaccinees. After 1999, however, invasive Hib disease increased, particularly in toddlers, and peaked in 2003. Potential reasons for the resurgence included a greater-than-expected decline in Hib antibodies after primary immunization, waning of herd immunity offered by the initial catch-up campaign, and use of a less immunogenic Hib combination vaccine containing acellular pertussis in 2000-2001. In response to the resurgence, a Hib combination vaccine containing whole-cell pertussis was reintroduced in 2002, followed by a childhood Hib booster campaign in 2003. In 2004, the recommended infant vaccine was changed to a different Hib/acellular pertussis combination vaccine containing inactivated polio, which had a satisfactory Hib response, was less reactogenic, and eliminated the risk of vaccine-associated paralytic poliomyelitis. This action was followed by introduction of a routine 12-month Hib booster in 2006. Together, these measures led to a decline in invasive Hib disease across all age groups. In 2010, there were only 30 invasive Hib cases, with 6 reported in children aged <5 years and no deaths in this age group since 2007. CONCLUSIONS Control of Hib disease is currently the best that has been achieved since the introduction of the routine Hib vaccination almost 20 years ago.
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Hallström T, Riesbeck K. Haemophilus influenzae and the complement system. Trends Microbiol 2010; 18:258-65. [PMID: 20399102 DOI: 10.1016/j.tim.2010.03.007] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2009] [Revised: 03/10/2010] [Accepted: 03/17/2010] [Indexed: 02/04/2023]
Abstract
The respiratory tract pathogen Haemophilus influenzae is responsible for a variety of infections in humans including septicemia, bronchitis, pneumonia, and acute otitis media. The pathogenesis of H. influenzae relies on its capacity to resist human host defenses including the complement system, and thus H. influenzae has developed several efficient strategies to circumvent complement attack. In addition to attracting specific host complement regulators directly to the bacterial surface, the capsule, lipooligosaccharides, and several outer membrane proteins contribute to resistance against complement-mediated attacks and hence increased bacterial survival. Insights into the mechanisms of complement evasion by H. influenzae are important for understanding pathogenesis and for developing vaccines and new therapies aimed at patients with, for example, chronic obstructive pulmonary disease. Here we overview current knowledge on the different mechanisms by which H. influenzae evades attack by the host complement system.
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Affiliation(s)
- Teresia Hallström
- Medical Microbiology, Department of Laboratory Medicine Malmö, Lund University, Skåne University Hospital, SE-205 02 Malmö, Sweden
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Invasive Disease Due to Type e Haemophilus influenzae. INFECTIOUS DISEASES IN CLINICAL PRACTICE 2008. [DOI: 10.1097/ipc.0b013e3181695607] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Jin Z, Romero-Steiner S, Carlone GM, Robbins JB, Schneerson R. Haemophilus influenzae type a infection and its prevention. Infect Immun 2007; 75:2650-4. [PMID: 17353280 PMCID: PMC1932902 DOI: 10.1128/iai.01774-06] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Affiliation(s)
- Zhigang Jin
- National Institutes of Health, Building 31, Room 2A29, Bethesda, MD 20892, USA
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Abstract
Haemophilus influenzae type b (Hib) is one of the leading causes of invasive bacterial infection in young children worldwide. During childhood, acquisition of antibody directed against the polysaccharide capsule of the organism, presumably as a result of asymptomatic carriage, confers protection and disease is much less common after the age of 4 years. Like other polysaccharides, the polyribosyl ribitol phosphate (PRP) of the Hib capsule is a T-independent antigen and not immunogenic when administered as a vaccine in infancy. Because the highest rates of disease occur in the first 2 years of life, efficacious Hib vaccines have been designed by covalently linking the PRP capsule to a carrier protein that recruits T-cell help for the polysaccharide immune response and induces anti-PRP antibody production even in the first 6 months of life. Introduction of Hib protein-polysaccharide conjugate vaccines into many industrialized countries over the past 15 years has resulted in the virtual elimination of invasive Hib disease. However, despite the success of the vaccine programme several factors may interfere with the effectiveness of the vaccine in the routine programme, as observed in the UK recently. Such factors may include interference with other concomitant vaccines, waning immunity in the absence of booster doses of vaccine, and reduced natural boosting as a result of decreased transmission of the organism. However, the burden of disease remains highest in resource-poor countries and urgent efforts are needed to provide the benefits of this vaccine for children living in regions where it cannot be used for economic and logistical reasons.
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Affiliation(s)
- Dominic F Kelly
- Department of Paediatrics, John Radcliffe Hospital, University of Oxford, Headington, Oxford, UK
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Nowak-Wegrzyn A, Winkelstein JA, Swift AJ, Lederman HM. Serum opsonic activity in infants with sickle-cell disease immunized with pneumococcal polysaccharide protein conjugate vaccine. The Pneumococcal Conjugate Vaccine Study Group. CLINICAL AND DIAGNOSTIC LABORATORY IMMUNOLOGY 2000; 7:788-93. [PMID: 10973456 PMCID: PMC95957 DOI: 10.1128/cdli.7.5.788-793.2000] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/23/1999] [Accepted: 05/13/2000] [Indexed: 01/19/2023]
Abstract
Pneumococcal infections are an important cause of morbidity and mortality in children with sickle-cell disease (SCD). Pneumococcal conjugate vaccines (PCVs) are immunogenic in healthy infants <2 years of age but have not been evaluated in young children with SCD. Infants with SCD were immunized with a 7-valent PCV (Wyeth-Lederle Vaccines & Pediatrics) at 2, 4, and 6 months of age. A booster dose of 23-valent pneumococcal polysaccharide vaccine (PPV; Pnu-Immune) was administered at 24 months of age. Antipneumococcal type 6B and 14 serum opsonic activity was measured to assess the biologic function of the antibody. Following the administration of three doses of PCV, opsonic activity against serotype 6B increased from 4. 8% at 2 months to 33.5% at 7 months, with a subsequent decline to 8.1% at 12 months and 7.5% at 24 months and with an increase to 30.7% at 25 months after administration of a booster dose of PPV. Similar trends were seen with serotype 14 (opsonic activities were 9.4% at 2 months, 24.9% at 7 months, 16.5% at 12 months, and 12.6% at 24 months, and the opsonic activity was 27.3% 1 month after the administration of PPV). Serum opsonic activity correlated with antibody levels for both serotypes. PCV induces serum opsonic activity in infants with SCD. Antipneumococcal serum opsonic activity correlates with antibody levels.
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Affiliation(s)
- A Nowak-Wegrzyn
- Eudowood Division of Allergy & Immunology, Department of Pediatrics, The Johns Hopkins University School of Medicine, Baltimore, Maryland 21287-3923, USA.
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