Efficacy of Immunization with Outer Membrane Proteins for Induction of Pulmonary Clearance of Nontypeable Haemophilus Influenzae in a Rat Respiratory Model

Three strains of nontypeable haemophilus influenzae namely nthi-i , nthi-ii and nthi-iiiwere isolated from the sputum of patients with bronchitis and identified by biochemical,serological and electron microscopy. the polypeptide patterns of isolates were compared andfound to have similar sodium dodecyl sulphate-polyacrylamide gel electrophoresis (sds-page)polypeptide patterns, although some of the bands were specific in some strains. a similarcomparison was made on extracted outer membrane proteins (omps) on the above mentionedstrains, using triton x-100 and sodium dodecyle sulphate (sds). it was found that thepolypeptides with molecular weights of 70, 42, 33 and 27 kda were identified as p1, p2, p4 andp5 respectivly. the protein estimation of crude omps from the three strains were calculated,and opm-i prepared from nthi–i showed the highest amount of protein and was chosen forits immunogenicity in a rat respiratory model.the efficacy of immunization with omp was determined by enhancement of pulmonaryclearance of live bacteria in the rat lung. a significant protective immune response induced byomp was observed by enhanced respiratory clearance of nontypeable h. influenzae followingmucosal immunization.