Efficacy of inactivated influenza vaccine delivered by oral administration

Migraine

Migraine is a common, chronic, disorder that is typically characterized by recurrent disabling attacks of headache and accompanying symptoms, including aura. The aetiology is multifactorial with rare monogenic variants. Depression, epilepsy, stroke and myocardial infarction are comorbid diseases. Spreading depolarization probably causes aura and possibly also triggers trigeminal sensory activation, the underlying mechanism for the headache. Despite earlier beliefs, vasodilation is only a secondary phenomenon and vasoconstriction is not essential for antimigraine efficacy. Management includes analgesics or NSAIDs for mild attacks, and, for moderate or severe attacks, triptans or 5HT_1B/1D receptor agonists. Because of cardiovascular safety concerns, unreliable efficacy and tolerability issues, use of ergots to abort attacks has nearly vanished in most countries. CGRP receptor antagonists (gepants) and lasmiditan, a selective 5HT1_F receptor agonist, have emerged as effective acute treatments. Intramuscular onabotulinumtoxinA may be helpful in chronic migraine (migraine on ≥15 days per month) and monoclonal antibodies targeting CGRP or its receptor, as well as two gepants, have proven effective and well tolerated for the preventive treatment of migraine. Several neuromodulation modalities have been approved for acute and/or preventive migraine treatment. The emergence of new treatment targets and therapies illustrates the bright future for migraine management.

Protection of mice against an influenza virus infection by oral vaccination with viral nucleoprotein incorporated into immunostimulating complexes

Influenza A virus nucleoprotein (NP) was integrated into immunostimulating complexes (ISCOMs) after attachment of bacterial lipopolysaccharide to the antigen. Oral immunization with these NP-ISCOMs protected mice fully against an otherwise lethal challenge infection with an unrelated influenza virus subtype without the appearance of severe clinical signs or extensive pathological lesions in the lungs. Mice immunized with analogous bovine serum albumine-incorporated ISCOMs all died. After oral immunization, high titers of NP-specific antibodies, particularly IgA, could be detected in the bronchoalveolar fluid and in the blood serum. No cytotoxic lymphocytes could be demonstrated in the spleens or the lungs of vaccinated mice, and no anti-NP antibody-dependent cytolysis of infected host cells was mediated by complement or in the form of an antibody-dependent cell cytotoxicity. However, a vigorous delayed-type hypersensitivity reaction was produced after probing vaccinated animals with purified NP. No comparable protective immunity or antibody response was induced by a strictly intragastric administration of NP-ISCOMs. It appears, therefore, that the general and local immune response in the lungs was primarily stimulated through contact of NP-ISCOMs with the mucous membrane of the oro-pharyngeal cavity and that cytotoxic effects did not play a major role for the establishment of the protective immunity. Partial protection against a lethal challenge was observed in chickens immunized with NP-ISCOMs in the drinking water.

Augmentation of anti-influenza virus hemagglutinin antibody production by Peyer's patch cells with Bifidobacterium breve YIT4064

Bifidobacterium breve YIT4064 was tested an an adjuvant for oral influenza vaccine by the murine Peyer's patch cell culture method. The organism augmented production of anti-influenza virus hemagglutinin immunoglobulin A antibody by Peyer's patch cells in response to addition of hemagglutinin. These antibodies may be disseminated to the respiratory mucosal tissue and prevent influenza virus infection.

Synthetic recombinant vaccine expressing influenza haemagglutinin epitope in Salmonella flagellin leads to partial protection in mice

The influenza virus haemagglutinin epitope 91-108, which is a conserved amino acid sequence in all type A H3 strains, was expressed in Salmonella flagellin, to evaluate its potential as a vaccine. For that purpose, a synthetic oligonucleotide comprising 54 bases coding for the corresponding sequence was inserted into the plasmid pLS408 and transformed into Escherichia coli JM101. Colonies containing the recombinant plasmid were used to transform Salmonella typhimurium LB5000 and were then transduced to a flagellin negative 'live vaccine' aroA mutant of Salmonella dublin. Rabbits immunized either with the live recombinant S. dublin or with the flagellin isolated from it, showed significant levels of IgG response against the synthetic peptide 91-108 as well as against the intact A/Texas/77 influenza virus. Mice immunized with the same preparations developed influenza-specific IgG antibodies in the blood and secreted IgA antibodies in their lungs. Furthermore, these mice showed about 50% protection against challenge infection with the virus. The most successful results were achieved by intranasal immunization with the isolated recombinant flagellin, when employed without the aid of adjuvant.