Effects of swine flu (H1N1) vaccine on albino rats

Abstract

The pandemic flu (2009) is a global outbreak of a new strain of H1N1 influenza virus that referred as "swine flu". The 2009 flu pandemic vaccines (H1N1 vaccines) are the biological preparation of influenza vaccines that have been developed to protect and improve immunity against the pandemic H1N1/09 virus. Squalene has been added to vaccine as immunologic adjuvant to stimulate the immune system, increase the response to the vaccine and reduce amount of usage vaccine. Thimerosal has been added to some vaccines as a preservative because it is effective in preventing bacterial contamination, particularly in multidose containers. To investigate the possible immunological effects of swine flu vaccine, Albino rats were injected with H1N1 antigen contained thimerosal, adjuvant and H1N1 vaccine. Results obtained in the present study showed that squalene and thimerosal contributed to the regiment of adverse reactions and symptoms, which act as detergents instead of its helper role of vaccine that undergone toxicity effectors in the biological pathways including; immunopathological and histopathological effects; the damage was done by vaccine, particularly when potentiated by powerful "immunoenhancers" caused a strong immunostimulation that emphasized by results of this research as well as its biological hazards which are more pronounced when act together as whole vaccine than they act individually so the adverse events that resulted from treatment with squalene-adjuvanted vaccine are more potent than those of either antigen or squalene-treated groups.

Caspase 3 role and immunohistochemical expression in assessment of apoptosis as a feature of H1N1 vaccine-caused Drug-Induced Liver Injury (DILI)

“…H1N1 vaccine can show adverse effects due to mixing the vaccine with adjuvants (e.g., squalene) in order to enhance antigen specific immune responses, as well as with preservatives (e.g., thimerosal) in order to prevent bacterial or fungal contamination ( 25 ). This leads to mercury induced cytotoxicity through its degradation and metabolism with ethyl mercury formation ( 25 ), and subsequently, according to Sanfeliuet al ( 25 , 32 ), production of reactive oxygen species. This results in apoptosis through induction of mitochondrial permeability transition, S phase arrest, and caspase 3 activation ( 27 ).…”

“…This is due to promotion of Fas agonists that induce hepatic chemokines and liver inflammation by the apoptotic hepatocytes ( 48 ), since the intense caspase 3 activity and processing through Fas or TNF receptors stimulation characterize the apoptotic cells ( 17 , 22 ). In addition, according to Fatma et al ( 25 ) and Viera 2001 ( 29 ), squalene as an adjuvant component of the H1N1 vaccine was reported to induce pathologic reactions including tissue necrosis, intense inflammation and granulomatous lesion. Against that, Martin et al, 2012 ( 21 ) mentioned that death receptor-mediated apoptosis is a non-inflammatory condition.…”

“…half of adult dose) at an elected date and a second dose administrated in at least three weeks. The recommended dose of rats equals the human dose multiplied by conversation factor (0.018)/200 gm of body weight of rat ( 25 , 38 ).…”

“…Vaccines often contain adjuvants (e.g., squalene) to enhance antigen specific immune responses, together with preservatives (e.g., Thimerosal) to prevent bacterial or fungal contamination ( 24 – 26 ), which are important for vaccine delivery ( 27 ). It was reported that squalene causes pathologic reactions at the injection site, together with mild erythema, muscle aches and swelling ( 25 , 28 ), followed by tissue necrosis, intense inflammation and granulomatous lesions ( 25 , 29 ), as well as Guillain Barre Syndrome ( 25 , 30 ). Moreover, when thimerosal is degraded or metabolized, ethyl mercury is formed ( 25 , 31 ) leading to reactive oxygen species (ROS) production, depletion of intracellular glutathione with subsequent mercury induced cytotoxicity ( 25 , 32 ).…”

“…It was reported that squalene causes pathologic reactions at the injection site, together with mild erythema, muscle aches and swelling ( 25 , 28 ), followed by tissue necrosis, intense inflammation and granulomatous lesions ( 25 , 29 ), as well as Guillain Barre Syndrome ( 25 , 30 ). Moreover, when thimerosal is degraded or metabolized, ethyl mercury is formed ( 25 , 31 ) leading to reactive oxygen species (ROS) production, depletion of intracellular glutathione with subsequent mercury induced cytotoxicity ( 25 , 32 ). Since mitochondria play a crucial role in regulation of apoptosis ( 27 , 33 , 34 ), thimerosal induces loss of mitochondrial membrane in T cells which is strongly associated with enhanced intracellular reactive oxygen species, release of cytochrome c and caspase 3 activation ( 27 ).…”