The immunosuppressive mini-domain of human lactoferrin

✍ Scribed by Ignacy Z. Siemion; Jacek Sloń; Zbigniew Wieczorek

• Publisher: John Wiley and Sons
• Year: 1995
• Tongue: English
• Weight: 491 KB
• Volume: 1
• Category: Article
• ISSN: 1075-2617
• DOI: 10.1002/psc.310010504

✦ Synopsis

Abstract

It has been found that the disulphide‐bridged 231–245 pentadecapeptide loop of the lactoferrin (LF) N‐lobe contains a region of immunosuppressive activity. The activity resides within a thymopentin‐like sequence (Arg‐Lys‐Pro‐Val‐Asp) of the loop. Peptides related to the 575–589 loop of the LF C‐lobe differ in their immunomodulatory activity from those related to the 231–245 loop. We ascribe this difference to the replacement of the Asp residue in the 231–245 loop by Thr in the 575–589 loop. Two other fragments of LF which were studied, 27–34 and 309–315, do not manifest any activy in the DTH test (cellular immune response), but, on testing in vivo, stimulate the humoral immune response. The 27–34 fragment is related to the bactericidal and immunostimulative region of LF identified by Bellamy et al. [1]. Our results show that the LF molecule contains, not only the known immunostimulating mini‐domain, but also a region endowed with immunosuppressive activity.