Adenovirus Vaccine Side Effects And Clinical Research

Adenovirus vaccine is a relativelynew type of vaccine, not an attenuated vaccine. It is mainly based on theadenovirus that is harmless to the human body and is not pathogenic, and usesgenetic engineering technology to process the adenovirus gene to a certainextent, making it an infectious agent that can only infect the human body forone cell cycle. The replication-defective virus then recombines the protectiveantigen gene into the adenovirus gene, so that the body can produce effectiveantibodies. So it belongs to a kind of genetic engineering vaccine. At present,the recombinant new coronavirus vaccine researched in China uses adenovirus asa carrier to replace part of the adenovirus gene with the spike glycoproteingene. This process is also called recombination. This glycoprotein is the keyprotein for the new coronavirus to invade the human body. If this recombinantprotein is recombined into an adenovirus vector, the adenovirus has certain characteristicsof the new coronavirus, so that the body can recognize it clearly, and usuallypay attention to the prevention of this disease.

Adenovirus vaccine features

Studies have found that adenovirusvectors carrying various antigens can stimulate the body to produce stronghumoral or cellular immunity. In addition, because adenoviral vectors caninfect respiratory and intestinal cells, they can easily immunize through themucosa, and can induce the body to produce mucosal and systemic immuneresponses.

Clinical study of adenovirusvaccine

1. Innate immune response inducedby adenovirus vector

The pathogen-associated molecularpattern of the adenovirus vector itself binds to the pattern recognitionreceptors on the cell surface, which promotes the secretion of inflammatorycytokines and the differentiation of immature dendritic cells into professionalantigen-presenting cells, activating the host's innate immune system. It wasshown that the secretion of IL6, il-1, and tnf-α could be detected by intravenousinjection of high doses of recombinant adenovirus expressing b-galactosidase inmice at 6h, and the aggregation of dendritic cells and macrophages at the edgeof the spleen was also observed in rhesus monkeys.

2. Adenovirus vaccine can rapidlystimulate the body to produce high levels of humoral immunity

Many vaccines protect the body fromdisease by stimulating the body to produce neutralizing antibodies. Adenovirusvaccines are effective in producing high levels of antibodies against thecorresponding target antigens. For example, replication-deficient orreplication-type 5 recombinant adenovirus vaccines carrying rabies virusglycoprotein can induce high levels of neutralizing antibodies and protectanimals against lethal doses of rabies virus challenge.

3. Adenovirus vaccine can stimulatethe body to produce strong cellular immunity

Specific T cell immunity plays animportant role in the fight against parasitic diseases, viral diseases andtumor therapy. A large number of preclinical and clinical studies have foundthat adenovirus vaccines can stimulate the body to produce strong specific Tcell responses against foreign genes. Some studies have reported that theadenovirus vector vaccine carrying the Plasmodium falciparum antigen METRAP canstimulate mice to produce a strong CD8T cell immune response, with a maximumprotection rate of 92%.

Adenovirus vaccine side effects

Adenovirus vaccines are exogenousantigens, which may stimulate the body to produce adverse reactions, and thecommon adenovirus vaccine side effects mainly include skin damage at thecontact site, systemic allergic reactions, and fever.

1. Skin damage: mainly due to thepossibility of local skin irritation after adenovirus vaccination, skinitching, redness, induration and other skin damage may occur at the vaccinationsite, and a systemic rash may occur in severe cases;

2. Systemic allergic reaction: Itis mainly because adenovirus vaccine stimulates the body to produce systemicallergic reaction, which may affect the function of the digestive system andrespiratory system, resulting in nausea, vomiting, diarrhea and othergastrointestinal adverse reactions. In severe cases, it may also causedifficulty breathing and laryngeal edema and other adverse reactions;

3. Fever: The main reason is thatthe adenovirus vaccine stimulates the human immune system to produceantibodies, resulting in an increase in the generation of endogenous pyrogens,resulting in low-grade adverse reactions, which generally disappear within 1-3days. However, some people with weakened immunity may also have high fever, orthe low fever persists. It is recommended to go to the hospital for medicaltreatment in time.

In addition, after adenovirusvaccination, it is recommended to eat light and easily digestible food, avoiddrinking alcohol and eating spicy, raw, cold and greasy food to avoidaggravating adverse reactions, and avoid eating food that can easily causeallergies, such as seafood and mango, to avoid triggering allergic reactions.

The probability of these adenovirusvaccine side effects is relatively low, and the duration is relatively short,so there is no need to worry too much. However, it is still necessary toobserve the adenovirus vaccine side effects. After the vaccine, you need toobserve the vaccination site for half an hour. If there are any adenovirus vaccineside effects, you need to report it to the doctor in time and deal with itearly, and most symptoms can be significantly improved. Usually also need morerest, do not overwork.