Synthesis and Characterization of Lipooligosaccharide-Based Conjugates as Vaccine Candidates for Moraxella ( Branhamella ) catarrhalis

Abstract

Moraxella (Branhamella)catarrhalis is an important cause of otitis media and sinusitis in children and of lower respiratory tract infections in adults. Lipooligosaccharide (LOS) is a major surface antigen of the bacterium and elicits bactericidal antibodies. Treatment of the LOS from strain ATCC 25238 with anhydrous hydrazine reduced its toxicity 20,000-fold, as assayed in the Limulus amebocyte lysate (LAL) test. The detoxified LOS (dLOS) was coupled to tetanus toxoid (TT) or high-molecular-weight proteins (HMP) from nontypeableHaemophilus influenzae through a linker of adipic acid dihydrazide to form dLOS-TT or dLOS-HMP. The molar ratios of dLOS to TT and HMP conjugates were 19:1 and 31:1, respectively. The antigenicity of the two conjugates was similar to that of the LOS, as determined by double immunodiffusion. Subcutaneous or intramuscular injection of both conjugates elicited a 50- to 100-fold rise in the geometric mean of immunoglobulin G (IgG) to the homologous LOS in mice after three injections and a 350- to 700-fold rise of anti-LOS IgG in rabbits after two injections. The immunogenicity of the conjugate was enhanced by formulation with monophosphoryl lipid A plus trehalose dimycolate. In rabbits, conjugate-induced antisera had complement-mediated bactericidal activity against the homologous strain and heterologous strains of M. catarrhalis. These results indicate that a detoxified LOS-protein conjugate is a candidate for immunization against M. catarrhalis diseases.

Moraxella catarrhalis lipooligosaccharide selectively upregulates ICAM-1 expression on human monocytes and stimulates adjacent naïve monocytes to produce TNF-α through cellular cross-talk

“…, 1992) was grown on chocolate agar plates at 37°C, 5% CO 2 . LOS was extracted from overnight culture by phenol‐water extraction as described previously (Gu et al. , 1998).…”

“…× 10 min) to tissue culture treated coverslips. Following fixation, cells were probed with affinity purified mouse monoclonal anti‐human CD14 (eBioscience) and rabbit anti‐LOS hyperimmune serum (Gu et al. , 1998) followed by NorthernLights FITC anti‐mouse IgG and Rhodamine Red™ X anti‐rabbit Ig (R&D Systems).…”

Exploration ofMoraxella catarrhalisouter membrane proteins, CD and UspA, as new carriers for lipooligosaccharide-based conjugates

“…LOS was detoxified and then derivatized to form adipic hydrazide (AH)-dLOS [14]. The AH-dLOS was conjugated to CD, UspA, or cross-reactive material, CRM9, a nontoxic mutant of diphtheria toxin provided by J.B. Robbins from National Institute of Child Health and Human Development, Bethesda, MD as a control [29].…”

The structure and biological characteristics of the Spirochaeta aurantia outer membrane glycolipid LGLB

“…LGL B was O-deacylated by hydrazinolysis, as described by Gu et al [25]. Briefly, 40 mg of LGL B was incubated with anhydrous hydrazine for 3 h at 37°C, with occasional mixing.…”