Conjugate based on cellulose nanoparticles and snake venoms for the production of antivenom serums

Conjugate based on cellulose nanoparticles and snake venoms for the production of antivenom serums.

U.K. Inogamov^a,b,R.K.Davranova^a, X.A.Abdullayev^a,Babahanov O^a.

^aTashkent Scientific Research Institute of Vaccines and Serums,Uzbekistan,
100084, Tashkent, Yunusabad district, Chingiz Aitmatov str., phone:[phone]
e-mail:[e-mail]
^bInstitute of Biophysics and Biochemistry at the National University

Venomous snakes Vipera lebertina, Echis carinatus and Vipera ursinii are widespread in the regions of Central Asia. The bite of these snakes can lead to the development of heart failure, decreased venous return, disruption of the structure and function of blood cells and blood thickening, inhibition of the functions of the central nervous system and a decrease in circulatory volume. In the treatment of bites of poisonous animals and insects, the most effective remedy is antitoxic immune serum. Antitoxic immune serums contain specific antibodies and they are able to neutralize the toxic effect of poisons. The difficulty of obtaining antisera is associated with high toxicity and low immunogenicity, due to the low molecular weight of the toxins of most poisons. Therefore, in order to develop an effective immune response for many antigens, it is necessary to introduce, together with the antigen, an adjuvant that nonspecifically stimulates the immune response to this antigen. Freund's adjuvant is usually used for these purposes.

However, the toxicity of Freund's adjuvants makes their use in practical healthcare difficult. Therefore, in recent years, new drugs with high adjuvant activity based on natural and synthetic polymers have been identified and obtained. At the same time, the use of whole venom for immunization may not be optimal, since during the process of antibody formation the majority of antibodies are formed to high-molecular-weight components of the venom compared to low-molecular-weight toxic peptides.
In addition, during the process of immunization of animals, necrosis and putrefaction of tissues are formed at the site of injection of poison. This leads to a decrease in the quality of the antiserum and the formation of unwanted antibodies against necrotic masses. Therefore, to prevent the above disadvantages, we used cellulose nanoparticles as an adjuvant. The use of cellulose as a matrix is ​​due to the fact that it is an unconventional adjuvant as a carrier for immunostimulation of antibody formation and has a number of advantages over other carriers (ease of preparation, lack of toxicity, cheap, readily available raw materials, unlimited shelf life). The goal of our research was the synthesis of conjugates based on cellulose nanoparticles and snake venoms to obtain highly effective and monospecific antisera against snake venoms. At the initial stage of our study, cellulose nanoparticles were prepared from a copper-ammonia solution. By treating with a sodium periodate solution, dialdehyde-derived cellulose nanoparticles were obtained. Snake venom was immobilized to cellulose nanoparticles in carbonate buffer. The conjugate synthesized in this way was used to immunize experimental animals. After 3 times immunization with the conjugate within a month, the titer of the antiserum was 1:16, and the specific antibodies in 1 ml were 10-15 mg. Thus, preliminary results showed that the use of a conjugate based on cellulose nanoparticles during the immunization process in animals did not cause any negative changes. The resulting anti-venom sera were highly specific for neutralizing the poison.