Saturday, May 30, 2009

Alloferons

Definition
Alloferons also known as immunomodulating peptides are slightly cationic and non-toxic antiviral peptides that are isolated from the blood of an insect. Alloferons have no teratogenic, embryotoxic or mutagenic properties.

Discovery
Alloferons were first isolated from bacteria-challenged larvae of an experimentally infected blow fly, Calliphora vicina (Diptera) 1. This species, along with other surgical maggots, has a long history of medical use in wound and ulcer healing

Classification
Alloferons are members of cytokine-like peptide family of the insect immune system. They are naturally occurring peptides, usually consisting of 12-13 amino acids. Twenty types of alloferons are found in nature and are classified as as alloferon 1 to alloferon 20. Alloferons 1 and 2 are natural peptides, alloferons 3 and 4 are truncated forms of alloferon 1. Alloferons 5-20 are modifications of variable fragments of the basic structure of alloferon2.

Structural characteristics
Alloferons are linear, nonglycosylated oligopeptide having a unique amino acid sequence of molecular mass of about 1265 Da. Amino acid sequences of alloferons are homologous to influenza B virus precursor protein.

Mechanism of action
Alloferons mediate signalling by NF-?B pathway to boost recognition of viral and tumor antigens3. They are known to induce the production of endogenic interferons that promote a cascade of defense responses and also enhance CD25 receptor expression. Cytotoxic lymphocytes are stimulated by alloferons upon recognition of nonself or aberrant cells that are subsequently lysed.

Function
Alloferons are useful in the treatment or prophylaxis of various infectious or oncological diseases where improvement of innate immunity, including interferon system and natural cell mediated cytotoxicity can have therapeutic significance4. Alloferons is used as antiviral agent in the treatment of infections caused by influenza virus, herpes virus, papillomatosis, viral hepatitis, AIDS and AIDS relevant secondary infections. They are known also known to have antitumour property, used in the treatment of oncological conditions like acute and chronic leukemia.

References

1. Chernysh S, Kim SI, Bekker G, Pleskach VA, Filatova NA, Anikin VB, Platonov VG, Bulet P (2002). Antiviral and antitumor peptides from insects. Proceedings of the National Academy of Sciences, 99(20):12628-12632.
2. Kim SI, Chernysh S, Bekker G, Makhaldiani NB, Hoffman J, Bulet P (2008). Alloferons—immunomodulatory peptides. Free patents online, 7462360.
3. Ryu MJ, Anikin V, Hong SH, Jeon H, Yu YG, Yu MH, Chernysh S, Lee C (2008). Activation of NF-kappaB by alloferon through down-regulation of antioxidant proteins and IkappaBalpha. Mol Cell Biochem, vol 313(1-2):91-102.
4. Chernysh S (2006). Antitumoral and antiviral peptides. European patent publication, EP 1 705 182 A1.

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