Immunoglobulin A (IgA) proteinase from Clostridium ramosum is the enzyme which cleaves IgA of both subclasses; in contrast, the other bacterial proteinases cleave only IgA1 proteins. Previous reports characterized the activity of proteinase naturally secreted by C. ramosum specific for the normal human serum IgA of IgA1 and IgA2m(1) subclasses and also for secretory IgA (SIgA). Its amino acid sequence was determined, and the recombinant proteinase which cleaved IgA of both subclasses was prepared. Here we report the optimized expression, purification, storage conditions and activity testing against purified human milk SIgA. The recombinant C. ramosum IgA proteinase isolated in the high degree of purity exhibited almost complete cleavage of SIgA of both subclasses. The proteinase remained active upon storage for more than 10 month at -20 °C without substantial loss of enzymatic activity. Purified SIgA fragments are suitable for studies of all antigen-binding and Fc-dependent functions of SIgA involved in the protection against infections with mucosal pathogens.
- Klíčová slova
- Clostridium ramosum, Enzymatic activity, IgA proteinase, Storage conditions,
- MeSH
- bakteriální proteiny chemie genetika MeSH
- Firmicutes enzymologie genetika MeSH
- imunoglobulin A sekreční chemie MeSH
- imunoglobuliny - Fab fragmenty * chemie izolace a purifikace MeSH
- imunoglobuliny - Fc fragmenty * chemie izolace a purifikace MeSH
- lidé MeSH
- proteasy chemie genetika MeSH
- rekombinantní proteiny chemie genetika MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- bakteriální proteiny MeSH
- imunoglobulin A sekreční MeSH
- imunoglobuliny - Fab fragmenty * MeSH
- imunoglobuliny - Fc fragmenty * MeSH
- proteasy MeSH
- rekombinantní proteiny MeSH
IL-2 and IL-15 are structurally relative cytokines that share two receptor subunits, CD132 (γ(c) chain) and CD122 (β chain). However, the expression pattern and physiological role of IL-2 and IL-15 private receptor α chains CD25 and IL-15Rα, respectively, are strikingly different. CD25, together with CD122 and CD132, forms a trimeric high affinity IL-2 receptor that is expressed and functions on cells acquiring an IL-2 signal. Conversely, IL-15Rα is expressed and binds IL-15 with high affinity per se already in the endoplasmic reticulum of the IL-15 producing cells and it presents IL-15 to cells expressing CD122/CD132 dimeric receptor in trans. Thus, while IL-2 is secreted almost exclusively by activated T cells and acts as a free molecule, IL-15 is expressed mostly by myeloid cells and works as a cell surface-associated cytokine. Interestingly, the in vivo biological activity of IL-2 can be dramatically increased through complexing with certain anti-IL-2 mAbs; such IL-2/anti-IL-2 mAbs immunocomplexes selectively stimulate the proliferation of a distinct population of immune cells, depending on the clone of the anti-IL-2 mAb used. IL-2/S4B6 mAb immunocomplexes are highly stimulatory for CD122(high) populations (memory CD8(+) T and NK cells) and intermediately also for CD25(high) populations (Treg and activated T cells), while IL-2/JES6-1 mAb immunocomplexes enormously expand only CD25(high) cells. Although IL-2 immunocomplexes are much more potent than IL-2 in vivo, they show comparable to slightly lower activity in vitro. The in vivo biological activity of IL-15 can be dramatically increased through complexing with recombinant IL-15Rα-Fc chimera; however, IL-15/IL-15Rα-Fc complexes are significantly more potent than IL-15 both in vivo and in vitro. In this review we summarize and discuss the features and biological relevance of IL-2/anti-IL-2 mAbs and IL-15/IL-15Rα-Fc complexes, and try to foreshadow their potential in immunological research and immunotherapy.
- Klíčová slova
- Anti-IL-2 mAb, Biological activity, IL-15, IL-15Rα-Fc chimera, IL-2, Immunocomplexes,
- MeSH
- buňky NK cytologie účinky léků imunologie MeSH
- CD8-pozitivní T-lymfocyty cytologie účinky léků imunologie MeSH
- imunoglobuliny - Fc fragmenty chemie MeSH
- imunokomplex genetika imunologie farmakologie MeSH
- interleukin-15 genetika imunologie farmakologie MeSH
- interleukin-2 genetika imunologie farmakologie MeSH
- lidé MeSH
- monoklonální protilátky chemie MeSH
- myši MeSH
- receptor interleukinu-15 - alfa-podjednotka genetika imunologie MeSH
- receptor interleukinu-2 - alfa-podjednotka genetika imunologie MeSH
- receptory interleukinů - společná gama-podjednotka genetika imunologie MeSH
- regulace genové exprese MeSH
- regulační T-lymfocyty cytologie účinky léků imunologie MeSH
- signální transdukce MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- přehledy MeSH
- Názvy látek
- IL15 protein, human MeSH Prohlížeč
- IL2RA protein, human MeSH Prohlížeč
- IL2RG protein, human MeSH Prohlížeč
- imunoglobuliny - Fc fragmenty MeSH
- imunokomplex MeSH
- interleukin-15 MeSH
- interleukin-2 MeSH
- monoklonální protilátky MeSH
- receptor interleukinu-15 - alfa-podjednotka MeSH
- receptor interleukinu-2 - alfa-podjednotka MeSH
- receptory interleukinů - společná gama-podjednotka MeSH
The structure of the Fc fragment of monoclonal antibody IgG2b from hybridom M75 of Mus musculus has been determined by single crystal X-ray diffraction. This is the first report of the structure of the murine immunoglobulin isotype IgG2b. The structure refined at 2.1 A resolution provides more detailed structural information about native oligosaccharides than was previously available. High-quality Fourier maps provide a clear identification of alpha-l-fucose with partial occupancy in the first branch of the antennary oligosaccharides. A unique Fc:Fc interaction was observed at the C(H)2-C(H)3 interface.
- MeSH
- glykosylace MeSH
- imunoglobulin G chemie MeSH
- imunoglobuliny - Fc fragmenty chemie MeSH
- imunokomplex chemie MeSH
- krystalizace MeSH
- krystalografie rentgenová metody MeSH
- monoklonální protilátky chemie MeSH
- myši MeSH
- oligosacharidy chemie MeSH
- sekundární struktura proteinů MeSH
- zvířata MeSH
- Check Tag
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- imunoglobulin G MeSH
- imunoglobuliny - Fc fragmenty MeSH
- imunokomplex MeSH
- monoklonální protilátky MeSH
- oligosacharidy MeSH
