Do Pili Play a Role in Pathogenicity of Haemophilus Influenzae Type B?

Pichichero, M. E.; Anderson, Patrick L.; Loeb, Marilyn R.; Smith, David H

doi:10.1016/s0140-6736(82)90161-1

Cited by 120 publications

(111 citation statements)

References 18 publications

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“…Restriction of the~4 kb product with AseI and DraI produced an identical pattern in the 21 strains producing an~4 kb hif amplicon, suggesting sequence similarity. The complete fimbrial cluster found in the fimbriated serotype b strain C54 is 7.76 kb and contains hicAB in addition to hifABCDE (Pichichero et al, 1982). The expression of haemagglutinating fimbriae only requires hifABCDE, so the function of hicAB in this strain is unknown.…”

Section: Discussionmentioning

confidence: 99%

“…Importantly, we report that isolates of Hif, regardless of their anatomical source or history of causing invasive disease, comprise a relatively homogeneous group that, taken as a whole, contains a high prevalence of known virulence factors and properties. (Wilcox & Smith, 1975), non-typable and serum-resistant strain INT-1 (R2866) (Nizet et al, 1996), non-typable strain 11 (R3945) , non-typable strain 12 (R2846) (Barenkamp & Leininger, 1992), fimbriated serotype b strain C54 (Pichichero et al, 1982) and serum-resistant strain Eagan (E1a) (Weller et al, 1977) were used as controls. Bacteria were stored at 280 uC in sterile skimmed milk and cultured at 37 uC in 5 % CO 2 on chocolate agar supplemented with 1 % (v/v) IsovitaleX (Becton Dickinson) or in Difco brain-heart infusion broth (Becton Dickinson) supplemented with haemin/HCl (10 mg ml 21 ; Sigma Chemical) (sBHI) and b-NAD + (10 mg ml 21 ; Sigma) and with agar (Bacto-Agar; Difco) for solid sBHI plates.…”

Section: Introductionmentioning

confidence: 99%

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Adhesin genes and serum resistance in Haemophilus influenzae type f isolates

Watson

Nelson

Nguyen

et al. 2013

Journal of Medical Microbiology

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The incidence of invasive infections due to Haemophilus influenzae has decreased significantly in developed countries with high rates of vaccination against H. influenzae serotype b (Hib). This vaccine provides no protection against H. influenzae serotype f (Hif), typically associated with invasive infections in adults with chronic disease and/or immunodeficiency, and rarely in otherwise healthy adults and children. The specific properties of Hif associated with virulence remain largely uncharacterized. A panel of 26 Hif strains consisting of both invasive disease-associated and mucosal surface non-invasive disease-associated isolates was surveyed by DNA fingerprinting, biotyping and PCR detection of hmw1, hmw2, hsf, the hif fimbrial locus and the lipooligosaccharide (LOS) biosynthetic island, and assessment of b-lactamase expression and determination of resistance to the bactericidal activity of normal adult human serum. Repetitive sequence-based PCR fingerprinting differentiated the 26 strains into three clusters, with the majority of isolates (22/26, 84.6 %) clustered into a single indistinguishable group. Most isolates (24/26, 92.3 %) were of biotype I and two isolates produced b-lactamase with detection of a conjugative plasmid, and the isolates displayed a range of resistances to the bactericidal activity of human serum. All 26 isolates carried the adhesin hsf, 21 carried a partial hif fimbrial operon and 4 had the adhesin genes hmw1/2. A LOS biosynthetic island was detected in 20 isolates consisting of the genes lic2BC. It was concluded that Hif has many recognized virulence properties and comprises a relatively homogeneous group independent of the anatomical source from which it was isolated. INTRODUCTIONHaemophilus influenzae, a human-restricted Gram-negative coccobacillus, is a commensal of the upper respiratory mucosa and a pathogen commonly causing airway mucosal disease and occasional invasive disease. Since Margaret Pittman's original description of capsular serotypes among H. influenzae isolates in 1931 (Pittman, 1931), H. influenzae serotype b (Hib) had been the most clinically significant strain causing invasive disease (e.g. meningitis, epiglottitis, septicaemia and osteomyelitis) in previously well infants and children (Aubrey & Tang, 2003). Since the early 1990s, routine administration of the Hib conjugate vaccines (which induce protective levels of anti-capsular antibody) has virtually eliminated Hib disease among infants and young children in developed countries (Agrawal & Murphy, 2011;Ladhani, 2012). However, the vaccine provides no protection from infection due to nonb serotypes, including H. influenzae serotype f (Hif), which remains a rare but significant cause of invasive infection. Given the reduction in Hib carriage among Hib conjugate vaccine recipients, concern exists as to whether invasive disease due to Hif or other non-b encapsulated strains will become more prevalent due to serotype replacement Abbreviations: BLNAR, b-lactamase-negative ampicillin-resistant; CSF, cerebrospinal ...

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Section: Discussionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Adhesin genes and serum resistance in Haemophilus influenzae type f isolates

Watson

Nelson

Nguyen

et al. 2013

Journal of Medical Microbiology

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“…Table 1 describes the bacterial strains used in this study. NTHI strains AAr176, AAr73, AAr49, AAr91, and Eagan were enriched for pilusexpressing (p ϩ ) variants as previously described (23). The H. influenzae biotype IV strains 6351, 785, 1595, 4162, 1216, and 597 were kindly donated by Timothy Murphy of the Buffalo Veteran's Administration Hospital, Buffalo, N.Y., and have been shown to possess the variant P6 phenotype that has been associated with the unique genospecies of H. influenzae strains that cause genital and neonatal infections (21,30).…”

mentioning

confidence: 99%

Analysis of Pilus Adhesins from Haemophilus influenzae Biotype IV Strains

et al. 2001

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A subset of nontypeable Haemophilus influenzae (NTHI) biotype IV isolates from the human genital tract or from infected newborn infants forms a cryptic genospecies characterized by, among other features, the presence of peritrichous pili. The objective of this study was to determine the similarity of these pili to hemagglutinating, HifA-and HifE-containing pili expressed by respiratory H. influenzae isolates. For this analysis, the presence of hifA and hifE and their gene products in NTHI biotype IV strains was assessed, the binding of H. influenzae biotype IV strains to human epithelial cells was characterized, possible genital tissue tropism of these isolates was explored, and the role of HifA-and HifE-possessing pili in the adhesion of NTHI biotype IV strains to human epithelial cells was determined. None of the six biotype IV NTHI isolates tested agglutinated human red blood cells, nor could they be enriched for hemagglutinating variants. Although hifA, which encodes the major structural subunit of hemagglutinating pili, and hifE, which encodes the tip adhesin of hemagglutinating pili, were detected by PCR from six and five, respectively, of the six biotype IV strains tested, neither HifA nor HifE (the gene products of hifA and hifE) were detected in any of these strains by Western blot analysis using antisera that recognize HifA and HifE of respiratory strains. Transmission electron microscopy showed no surface pili on the two biotype IV H. influenzae isolates examined; strain 4162 containing an insertional mutation in hifA also showed no surface pili, whereas strain 1595 containing an insertional mutation in hifB showed pilus-like structures that were shorter and thicker than hemagglutinating pili of the respiratory strains AAr176 and M43. In enzyme-linked immunosorbent assays, biotype IV strains adhered to 16HBE14o ؊ and HEp-2 cells of respiratory origin as well as to ME180 and HeLa cells of genital origin. This adherence was not pilus specific, however, as GM-1, a known pilus receptor analog, did not inhibit binding of biotype IV strains to ME180, HEp-2, or HeLa cells, and GM-1 inhibition of binding to 16HBE14o ؊ cells did not correlate with the presence of hifE. While both nonpiliated variants and hifA and hifB (encoding the pilus chaperone) mutants of respiratory strain AAr176 showed reduced binding (64 to 87% of that of piliated AAr176) to 16HBE14o ؊ and ME180 cells, hifA and hifB mutants of the biotype IV strains showed minimal reduction in binding to these cell lines (91 to 98% of that of wild-type strains). Thus, although biotype IV H. influenzae isolates of the cryptic genospecies possess the genes that code for HifA-and HifE-containing hemagglutinating pili, epithelial cell adherence exhibited by these strains is not mediated by expression of hemagglutinating pili.Nontypeable Haemophilus influenzae (NTHI; i.e., strains lacking a polysaccharide capsule) strains colonize the human pharynx and nasopharynx and may cause respiratory infections such as otitis media, bronchitis, sinusitis, and pneumonia...

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“…Polysaccharides vaccines for pneumococcal disease, meningococcal disease [41], Haemophilus influenza type b (Hib) [48,49] and Salmonella Typhi [50,51] are examples. In the late 1980s, it was discovered that the problems of less antigenic due to the polysaccharide cotes could be overcome through a process called conjugation.…”

Section: Polysaccharides-conjugate Vaccinementioning

confidence: 99%

Vaccines against Pathogens: A Review and Food For Thought

Amara¹

2016

SOJB

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Do Pili Play a Role in Pathogenicity of Haemophilus Influenzae Type B?

Cited by 120 publications

References 18 publications

Adhesin genes and serum resistance in Haemophilus influenzae type f isolates

Adhesin genes and serum resistance in Haemophilus influenzae type f isolates

Analysis of Pilus Adhesins from Haemophilus influenzae Biotype IV Strains

Vaccines against Pathogens: A Review and Food For Thought

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