Liposomes functionalized with monoclonal antibodies or their antigen-binding fragments have attracted much attention as specific drug delivery devices for treatment of various diseases including cancer. The conjugation of antibodies to liposomes is usually achieved by covalent coupling using cross-linkers in a reaction that might adversely affect the characteristics of the final product. Here we present an alternative strategy for liposome functionalization: we created a recombinant Fab antibody fragment genetically fused on its C-terminus to the hydrophobic peptide derived from pulmonary surfactant protein D, which became inserted into the liposomal bilayer during liposomal preparation and anchored the Fab onto the liposome surface. The Fab-conjugated liposomes specifically recognized antigen-positive cells and efficiently delivered their cargo, the Alexa Fluor 647 dye, into target cells in vitro and in vivo. In conclusion, our approach offers the potential for straightforward development of nanomedicines functionalized with an antibody of choice without the need of harmful cross-linkers.

• Klíčová slova
• Active targeting, Antibody engineering, Immunoliposome, Liposome functionalization, Recombinant Fab antibody fragment,
• MeSH
• antigen CD48 metabolismus   MeSH
• antigeny CD59 metabolismus   MeSH
• imunoglobuliny - Fab fragmenty chemie   imunologie   metabolismus   MeSH
• Jurkat buňky MeSH
• lidé MeSH
• liposomy chemie   MeSH
• lymfom imunologie   metabolismus   patologie   MeSH
• monoklonální protilátky chemie   imunologie   metabolismus   MeSH
• myši MeSH
• nádorové buňky kultivované MeSH
• peptidové fragmenty imunologie   metabolismus   MeSH
• protein D asociovaný s plicním surfaktantem imunologie   metabolismus   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• antigen CD48 MeSH
• antigeny CD59 MeSH
• CD48 protein, human MeSH Prohlížeč
• CD59 protein, human MeSH Prohlížeč
• imunoglobuliny - Fab fragmenty MeSH
• liposomy MeSH
• monoklonální protilátky MeSH
• peptidové fragmenty MeSH
• protein D asociovaný s plicním surfaktantem MeSH

Complement consumption induced by Fab' fragments of rabbit IgG, irrespectively of their state of aggregation, requires the presence of homologous rabbit IgG. Up to a certain concentration of Fab' fragment, the amount of complement fixed is a linear function of the Fab' fragment dose, but further raising of the Fab'-fragment concentration does not result in complete complement consumption in the sample. The interaction between Fab' fragment and IgG is not strictly species specific.

• MeSH
• druhová specificita MeSH
• gama-globuliny metabolismus   MeSH
• imunoglobuliny - Fab fragmenty * MeSH
• komplement fixační testy * MeSH
• králíci MeSH
• morčata MeSH
• zvířata MeSH
• Check Tag
• králíci MeSH
• morčata MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• gama-globuliny MeSH
• imunoglobuliny - Fab fragmenty * MeSH

Forty % of serum IgM and 47% of dimeric colostral IgA were bound to protein A-Sepharose. Fab mu and Fab alpha fragments showed a reactivity similar to that of the whole immunoglobulins. Complete elutions of IgM and IgA from the protein A-Sepharose were obtained in lower cocentrations of MgCl2 than the complete elution of IgG. However, IgM and IgA were completely eluted at higher concentrations of MgCl2 in the presence of IgG than in its absence.

• MeSH
• chromatografie afinitní MeSH
• hořčík farmakologie   MeSH
• imunoglobulin A metabolismus   MeSH
• imunoglobulin M metabolismus   MeSH
• imunoglobuliny - alfa-řetězce MeSH
• imunoglobuliny - Fab fragmenty * MeSH
• imunoglobuliny - mu-řetězce MeSH
• prasata MeSH
• stafylokokový protein A metabolismus   MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• hořčík MeSH
• imunoglobulin A MeSH
• imunoglobulin M MeSH
• imunoglobuliny - alfa-řetězce MeSH
• imunoglobuliny - Fab fragmenty * MeSH
• imunoglobuliny - mu-řetězce MeSH
• stafylokokový protein A MeSH

Ninety % of pig serum IgG was bound to protein A-Sepharose. Both individual fractions of the IgG, separated on the basis of their electric charge, were adsorbed on protein A-Sepharose to a similar extent. However, these fractions differed in their elution profile from the protein A-Sepharose when a gradient of increasing molarity of MgCl2 was used. Relative amounts of fractions eluted in higher concentrations of MgCl2 were augmented with the increasing amount of IgG bound to SpA-Sepharose. Not only high proportions of Fc fragments, but also nearly half of Fab fragments reacted with protein A. This latter interaction, confirmed also by affinity electrophoresis, did not have the character of a specific reaction of antibody with antigen.

• MeSH
• chromatografie afinitní MeSH
• dinitrofenoly imunologie   MeSH
• hořčík farmakologie   MeSH
• imunoglobulin G metabolismus   MeSH
• imunoglobuliny - Fab fragmenty * MeSH
• imunoglobuliny - Fc fragmenty MeSH
• králíci MeSH
• lehké řetězce imunoglobulinů MeSH
• lidé MeSH
• prasata MeSH
• sefarosa MeSH
• sérový albumin imunologie   MeSH
• skot MeSH
• stafylokokový protein A metabolismus   MeSH
• těžké řetězce imunoglobulinů MeSH
• zvířata MeSH
• Check Tag
• králíci MeSH
• lidé MeSH
• skot MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• dinitrofenoly MeSH
• hořčík MeSH
• imunoglobulin G MeSH
• imunoglobuliny - Fab fragmenty * MeSH
• imunoglobuliny - Fc fragmenty MeSH
• lehké řetězce imunoglobulinů MeSH
• sefarosa MeSH
• sérový albumin MeSH
• stafylokokový protein A MeSH
• těžké řetězce imunoglobulinů MeSH

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

Precipitating and non-precipitating anti-Dnp antibodies and S-sulpho non-specific IgG in gram quantities were subjected to limited cleavage by trypsin. Upon gel chromatography on Sephadex G-100 the fraction of Fab and Fc fragments was separated from incompletely split molecules and from tFc' fragments. The Fab and Fc fragments were separated from each other either by ion-exchange chromatography on QAE-Sephadex or by preparative electrophoresis in starch block. Both Fab and Fc fragments appeared to be heterogeneous as to electric charge. The Fc fragments were characterized by amino acid composition and N-terminal amino acids. The Fc fragment of non-specific IgG was cleaved by cyanogen bromide, and a C-terminal peptide containing 18 residues was isolated. Partial amino acid sequence of this peptide pointed to a high degree of homology with immunoglobulins of other animal species.

• MeSH
• aminokyseliny analýza   MeSH
• bromkyan MeSH
• dinitrofenoly imunologie   MeSH
• imunoglobulin G analýza   MeSH
• imunoglobuliny - Fab fragmenty izolace a purifikace   MeSH
• imunoglobuliny - Fc fragmenty izolace a purifikace   MeSH
• imunoglobuliny - fragmenty izolace a purifikace   MeSH
• peptidy analýza   MeSH
• prasata imunologie   MeSH
• precipitiny analýza   MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• aminokyseliny MeSH
• bromkyan MeSH
• dinitrofenoly MeSH
• imunoglobulin G MeSH
• imunoglobuliny - Fab fragmenty MeSH
• imunoglobuliny - Fc fragmenty MeSH
• imunoglobuliny - fragmenty MeSH
• peptidy MeSH
• precipitiny MeSH

To study intramolecular motility, the binding sites of the antibodies or Fab fragments were occupied by the spin-labelled hapten Dnp-NO. EPR spectra of the complexes were recorded under various conditions, in particular variable viscosity, and the correlation times of the antibody or its fragment were calculated. Intramolecular motility decreases, i.e. correlation time increases, with temperature in the range from 5 degree C to 30 degrees C. This anomalous dependence points to the important role of hydrophobic bonds in the interactions between domains of the antibody molecule. Substitution of a fraction of H2O by D2O (1 to 13%) is manifested by the increase in correlation time only at 5 degrees C, a maximal effect is already obtained at about 3% D2O. At 20 degrees C or in the presence of perturbants of the hydration shell such as 0.5 M sodium chloride, 1 M urea or 10% butanol, D2O has no appreciable effect. EPR spectra made it possible to study the gradual immobilization of the bound spin-labelled hapten at temperatures lower than 0 degrees C. Water in the vicinity of the bound spin-labelled hapten freezes in three discrete steps, -8 to -13 degrees C, -20 to -40 degrees C, and -40 to -80 degrees C. D2O influences the first and second step so that it shifts the transition to higher temperatures. The results contribute to our understanding of the fine structure of the hydration shell and water in the interdomain space of the antibody molecule.

• MeSH
• deuterium metabolismus   MeSH
• dinitrobenzeny imunologie   MeSH
• elektronová paramagnetická rezonance MeSH
• hapteny metabolismus   MeSH
• imunoglobuliny - Fab fragmenty metabolismus   MeSH
• konformace proteinů MeSH
• oxid deuteria MeSH
• prasata MeSH
• protilátky metabolismus   MeSH
• spinové značení MeSH
• teplota MeSH
• vazebná místa protilátek * MeSH
• voda metabolismus   MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• deuterium MeSH
• dinitrobenzeny MeSH
• hapteny MeSH
• imunoglobuliny - Fab fragmenty MeSH
• oxid deuteria MeSH
• protilátky MeSH
• spinové značení MeSH
• voda MeSH

125I-labelled Fab antidigitalis antibodies were administered i.p. to rats, whose organs were removed 20 h later and examined for radioactivity. Maximum radioactivity was found in the thyroid region, followed by the kidneys, liver, adrenals, heart, skeletal muscle and brain. The radioactivity of kidneys was greater than in any of the other organs except the thyroid, where it probably resulted from the uptake of radioiodine, released from the antibodies. After injection of Na125I there was no difference between the kidneys and the liver. In kidney homogenates, radioactivity was present both in the 100,000xg pellet and in the supernatant. The possibility of accumulation or production of the endogenous digitalis-like factor in the kidneys is discussed.

• MeSH
• Digitalis imunologie   MeSH
• imunoglobuliny - Fab fragmenty aplikace a dávkování   MeSH
• inbrední kmeny potkanů MeSH
• jedovaté rostliny * MeSH
• krysa rodu Rattus MeSH
• léčivé rostliny * MeSH
• ledviny diagnostické zobrazování   MeSH
• orgánová specificita MeSH
• radioaktivita MeSH
• radioisotopová scintigrafie MeSH
• radioizotopy jodu * MeSH
• zvířata MeSH
• Check Tag
• krysa rodu Rattus MeSH
• mužské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• imunoglobuliny - Fab fragmenty MeSH
• radioizotopy jodu * MeSH

Natural antibodies (Abs) can target host glycans on the surface of pathogens. We studied the evolution of glycan-reactive B cells of rhesus macaques and humans using glycosylated HIV-1 envelope (Env) as a model antigen. 2G12 is a broadly neutralizing Ab (bnAb) that targets a conserved glycan patch on Env of geographically diverse HIV-1 strains using a unique heavy-chain (VH) domain-swapped architecture that results in fragment antigen-binding (Fab) dimerization. Here, we describe HIV-1 Env Fab-dimerized glycan (FDG)-reactive bnAbs without VH-swapped domains from simian-human immunodeficiency virus (SHIV)-infected macaques. FDG Abs also recognized cell-surface glycans on diverse pathogens, including yeast and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike. FDG precursors were expanded by glycan-bearing immunogens in macaques and were abundant in HIV-1-naive humans. Moreover, FDG precursors were predominately mutated IgM+IgD+CD27+, thus suggesting that they originated from a pool of antigen-experienced IgM+ or marginal zone B cells.

• Klíčová slova
• FDG Abs, Fab dimerization, HIV-1 Env glycans, IgM-memory B cells, SARS-CoV-2 spike glycans, glycan-dependent Ab binding, marginal zone B cells, natural Abs,
• MeSH
• B-lymfocyty imunologie   MeSH
• COVID-19 imunologie   MeSH
• dimerizace MeSH
• epitopy imunologie   MeSH
• genové produkty env - virus lidské imunodeficience chemie   genetika   imunologie   MeSH
• glykoprotein S, koronavirus imunologie   MeSH
• glykosylace MeSH
• HIV infekce imunologie   MeSH
• HIV protilátky imunologie   MeSH
• HIV-1 imunologie   MeSH
• imunoglobuliny - Fab fragmenty chemie   imunologie   MeSH
• lidé MeSH
• Macaca mulatta MeSH
• neutralizující protilátky imunologie   MeSH
• polysacharidy chemie   imunologie   MeSH
• receptory antigenů B-buněk chemie   MeSH
• SARS-CoV-2 imunologie   MeSH
• široce neutralizující protilátky imunologie   MeSH
• vakcíny imunologie   MeSH
• virus opičí imunodeficience genetika   imunologie   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Research Support, N.I.H., Extramural MeSH
• Názvy látek
• epitopy MeSH
• genové produkty env - virus lidské imunodeficience MeSH
• glykoprotein S, koronavirus MeSH
• HIV protilátky MeSH
• imunoglobuliny - Fab fragmenty MeSH
• neutralizující protilátky MeSH
• polysacharidy MeSH
• receptory antigenů B-buněk MeSH
• široce neutralizující protilátky MeSH
• spike protein, SARS-CoV-2 MeSH Prohlížeč
• vakcíny MeSH

A two-component CD20 (non-internalizing) receptor crosslinking system based on the biorecognition of complementary coiled-coil forming peptides was evaluated. Exposure of B cells to Fab'-peptide1 conjugate decorates the cell surface with peptide1; further exposure of the decorated cells to P-(peptide2)x (P is the N-(2-hydroxypropyl)methacrylamide (HPMA) copolymer backbone) results in the formation of coiled-coil heterodimers at the cell surface with concomitant induction of apoptosis. The aim of this study was to determine the potential immunogenicity of this therapeutic system that does not contain low molecular weight drugs. Enantiomeric peptides (L- and D-CCE and L- and D-CCK), HPMA copolymer-peptide conjugates, and Fab' fragment-peptide conjugates were synthesized and the immunological properties of peptide conjugates evaluated in vitro on RAW264.7 macrophages and in vivo on immunocompetent BALB/c mice. HPMA copolymer did not induce immune response in vitro and in vivo. Administration of P-peptide conjugates with strong adjuvant resulted in antibody response directed to the peptide. Fab' was responsible for macrophage activation of Fab'-peptide conjugates and a major factor in the antibody induction following i.v. administration of Fab'-conjugates. There was no substantial difference in the ability of conjugates of D-peptides and conjugates of L-peptides to induce Ab response.

• Klíčová slova
• Coiled-coil peptides, Drug-free macromolecular therapeutics, Enantiomers, Fab' fragment, HPMA copolymer, Immunogenicity,
• MeSH
• akrylamidy aplikace a dávkování   chemie   imunologie   MeSH
• buněčné linie MeSH
• imunoglobuliny - Fab fragmenty aplikace a dávkování   chemie   imunologie   MeSH
• makrofágy účinky léků   imunologie   MeSH
• molekulární sekvence - údaje MeSH
• myši inbrední BALB C MeSH
• myši MeSH
• peptidy aplikace a dávkování   chemie   imunologie   MeSH
• sekvence aminokyselin MeSH
• T-lymfocyty účinky léků   imunologie   MeSH
• tvorba protilátek účinky léků   MeSH
• zvířata MeSH
• Check Tag
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Research Support, N.I.H., Extramural MeSH
• Názvy látek
• akrylamidy MeSH
• imunoglobuliny - Fab fragmenty MeSH
• N-(2-hydroxypropyl)methacrylamide MeSH Prohlížeč
• peptidy MeSH