Defensin carriers for better mucosal immunity in the digestive system.
The innate immunity utilizes a battery of broad-spectrum antibacterial cationic polypeptides named defensins. In humans, defensins are the first line of defense against pathogens, and their expression has been implicated in several diseases. In addition to exerting direct antimicrobial effects, defensins facilitate and amplify innate and adaptive immune responses. HD-5 is a polypeptide that plays a pivotal role in combating bacteria in the digestive system. Our results show that HD-5 can be entrapped within alginate carriers and strengthen their structure without changing their brittleness. In addition, carrier-entrapped HD-5 is released when incubated in buffer and/or stomach-simulating solution and still retains its activity after the release. This incubation also led to a decrease in carrier strength as well as an increase in their brittleness. Nevertheless the carriers did not disintegrate and remained intact throughout the diffusion process. The release of the defensin exhibited a bimodal behavior, suggesting that it was found both in a cross-linked and non-cross-linked form within the carrier. These results indicate that defensins encapsulated within alginate carriers could possibly be used for better mucosal immunity in the digestive system.
Froy
Oren
O
Institute of Biochemistry, Food Science and Nutrition, Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, P.O. Box 12, Rehovot 76100, Israel. froy@agri.huji.ac.il
Chapnik
Nava
N
Nussinovitch
Amos
A
D000464:Alginates / Q000737:chemistry*; D002021:Buffers; D002626:Chemistry, Pharmaceutical; D004058:Diffusion; D004337:Drug Carriers; D004339:Drug Compounding; D004355:Drug Stability; D005750:Gastric Juice / Q000737:chemistry; D020723:Glucuronic Acid / Q000737:chemistry; D006603:Hexuronic Acids / Q000737:chemistry; D006801:Humans; D018928:Immunity, Mucosal / Q000187:drug effects*; D007413:Intestinal Mucosa / Q000187:drug effects* / Q000276:immunology; D007419:Intestinal Secretions / Q000737:chemistry; D007421:Intestine, Small / Q000187:drug effects* / Q000276:immunology; D007700:Kinetics; D011994:Recombinant Proteins / Q000494:pharmacology; D012995:Solubility; D013678:Technology, Pharmaceutical / Q000379:methods; D023084:alpha-Defensins / Q000737:chemistry / Q000494:pharmacology*
D000464:Alginates; D002021:Buffers; C500225:DEFA5 protein, human; D004337:Drug Carriers; D006603:Hexuronic Acids; D011994:Recombinant Proteins; D023084:alpha-Defensins; D020723:Glucuronic Acid