Lipid content of swine influenza and other vaccines

Autoantibodies against ganglioside GM3 are associated with narcolepsy-cataplexy developing after Pandemrix vaccination against 2009 pandemic H1N1 type influenza virus

Following the mass vaccinations against pandemic influenza A/H1N1 virus in 2009, a sudden increase in juvenile onset narcolepsy with cataplexy (NC) was detected in several European countries where AS03-adjuvanted Pandemrix vaccine had been used. NC is a chronic neurological disorder characterized by excessive daytime sleepiness and cataplexy. In human NC, the hypocretin-producing neurons in the hypothalamus or the hypocretin signaling pathway are destroyed by an autoimmune reaction. Both genetic (e.g. HLA-DQB1*0602) and environmental risk factors (e.g. Pandemrix) contribute to the disease development, but the underlying and the mediating immunological mechanisms are largely unknown. Influenza virus hemagglutinin is known to bind gangliosides, which serve as host cell virus receptors. Anti-ganglioside antibodies have previously been linked to various neurological disorders, like the Guillain-Barré syndrome which may develop after infection or vaccination. Because of these links we screened sera of NC patients and controls for IgG anti-ganglioside antibodies against 11 human brain gangliosides (GM1, GM2, GM3, GM4, GD1a, GD1b, GD2, GD3, GT1a, GT1b, GQ1b) and a sulfatide by using a line blot assay. Samples from 173 children and adolescents were analyzed: 48 with Pandemrix-associated NC, 20 with NC without Pandemrix association, 57 Pandemrix-vaccinated and 48 unvaccinated healthy children. We found that patients with Pandemrix-associated NC had more frequently (14.6%) anti-GM3 antibodies than vaccinated healthy controls (3.5%) (P = 0.047). Anti-GM3 antibodies were significantly associated with HLA-DQB1*0602 (P = 0.016) both in vaccinated NC patients and controls. In general, anti-ganglioside antibodies were more frequent in vaccinated (18.1%) than in unvaccinated (7.3%) individuals (P = 0.035). Our data suggest that autoimmunity against GM3 is a feature of Pandemrix-associated NC and that autoantibodies against gangliosides were induced by Pandemrix vaccination.

Implications for lipids during replication of enveloped viruses

Enveloped viruses, which include many medically important viruses such as human immunodeficiency virus, influenza virus and hepatitis C virus, are intracellular parasites that acquire lipid envelopes from their host cells. Success of replication is intimately linked to their ability to hijack host cell mechanisms, particularly those related to membrane dynamics and lipid metabolism. Despite recent progress, our knowledge of lipid mediated virus-host interactions remains highly incomplete. In addition, diverse experimental systems are used to study different stages of virus replication thus complicating comparisons. This review aims to present a unifying view of the widely diverse strategies used by enveloped viruses at distinct stages of their replication cycles.

Relationship of adjuvants and swine influenza vaccine to experimental neuropathy in rabbits

Experimental neuropathy, characterized by endoneurial edema and demyelination, was induced by inoculating rabbits with a combination of Freund's complete adjuvant (FCA), gangliosides, lecithin and cholesterol. A less severe demyelinating neuropathy could be induced by treatment with FCA alone but no significant change could be elicited by injection of swine influenza vaccine (SFV) alone. When FCA was combined with gangliosides, lecithins, cholesterol and SFV, neuropathy occurred, but the changes were less severe than if these agents were used without SFV. Sera were tested for myelin basic protein (MBP) and galactocerebroside (GC) antibodies in each experimental group. Neither SFV alone nor SFV combined with Freund's complete adjuvant, gangliosides, cholesterol and lecithin evoked significant antibody titers to MBP or GC. However, rabbits inoculated with FCA, gangliosides, lecithin and cholesterol had rising titers of antibody to both MBP and GC over the 3-month experimental period. One rabbit inoculated with FCA alone had significant antibody to MBP. The findings suggest that Freund's complete adjuvant alone can induce demyelination in the peripheral nerves of rabbits and that SFV may modulate the immune response acting either as an adjuvant or suppressant in the experimental demyelinating disease.