Alfredo De Ioannes - Profile on Academia.edu (original) (raw)
Papers by Alfredo De Ioannes
Preliminary Structural Characterization of Pacific Hagfish Immunoglobulin
Advances in Experimental Medicine and Biology, 1975
The immune capacities of primitive fishes of the class Agnatha, the lamprey and the hagfish, have... more The immune capacities of primitive fishes of the class Agnatha, the lamprey and the hagfish, have been under study for nearly a decade. Early results from Good and his collaborators suggested that lampreys, but not hagfish, possessed an adaptive immune response (1, 2). However, subsequent work of Linthicum and Hildemann (3) and Hildemann and Thoenes (4, 5) showed that hagfish (Eptatretus stoutii) could also respond specifically to certain immunogens and could reject allografts under appropriate conditions.
Síntesis y secreción del antígeno de superficie del virus de hepatitis B en cultivo de células animales
Biological research, 1992
Mammalian sperm acrosomes contain a trypsin-like protease called acrosin which causes limited and... more Mammalian sperm acrosomes contain a trypsin-like protease called acrosin which causes limited and specific hydrolysis of the extracellular matrix of the mammalian egg, the zona pellucida. Acrosin was localized on hamster, guinea-pig and human sperm using monoclonal and polyclonal antibodies to human acrosin labelled with colloidal gold. This was visualized directly with transmission electron microscopy, and with light and scanning microscopy after silver enhancement of the colloidal gold probe. Four distinct labelling patterns were found during capacitation and the acrosome reaction in hamster and guinea-pig spermatozoa, and three patterns were found in human spermatozoa. In the hamster, acrosin was not detected on the inner acrosomal surface after the completion of the acrosome reaction, thus correlating with the observation that hamster spermatozoa lose the ability to penetrate the zona after the acrosome reaction. With guinea-pig and human spermatozoa, acrosin was still detected ...
Developmental & Comparative Immunology, 1981
Photochemistry and Photobiology, 2008
The anaerobic phototransformation of tyrosine under visible light sensitized by riboflavin is rep... more The anaerobic phototransformation of tyrosine under visible light sensitized by riboflavin is reported. The cytotoxicity of the anaerobic photoproducts on in vitro-cultured myeloid mouse tumoral cells was demonstrated. A radical mechanism is proposed. Dityrosine was identified as one of the main anaerobic photoproducts by using absorption, emission and 'H-NMR spectra.
Photochemistry and Photobiology, 1999
The effect of the photoproducts of indole-3-acetic acid sensitized by riboflavin on nonirradiated... more The effect of the photoproducts of indole-3-acetic acid sensitized by riboflavin on nonirradiated human HL-60 and murine NS0/2 tumor cells was studied. Severe damage with a dose-response effect was observed on both cell types. The effect was greater than that previously described for the tryptophan riboflavin photoproducts. Electron microscopy studies and flow cytometry analysis of DNA fragmentation allowed us to conclude that the photoproducts studied in this work induce cell death by an apoptotic mechanism.
Journal of Reproductive Immunology, 2007
Females in numerous rodent species engage in communal nesting and breeding, meaning that they sha... more Females in numerous rodent species engage in communal nesting and breeding, meaning that they share a nest to rear their young together. One potential benefit to communally nesting mothers is that infants improve their immunocompetence. Thus, suckling from two or more females might provide newborns with a more diverse array of antibodies and defensive cells. As a first step toward testing the immunocompetence hypothesis, we assessed whether female degus (Octodon degus), a communally nesting and breeding caviomorph rodent, transfer immunoglobulins to their young through the yolk sac or placenta while in the uterus and, during lactation, through milk. With this aim, adult degu females were immunized with four antigens, including two mollusk hemocyanins from Concholepas and Megathura (CCH and KLH, respectively), porcine thyroglobulin and tetanus toxoid. Specific antibodies against the experimental antigens were used to track the origin of antibodies in the young. To establish the presence of specific antibodies of IgG and IgA isotypes in sera and milk of animals, an indirect enzyme-linked immunosorbent assay (ELISA) was developed. Degu females produced specific antibodies against antigens not found in their natural environment, and mothers were able to transfer the induced antibodies to their litters during pregnancy (IgG) and during lactation (IgA). However, we recorded only limited evidence of degu offspring acquiring antibodies from lactating mothers other than their own, giving little support to the increased immunocompetence hypothesis.
Journal of Agricultural and Food Chemistry, 1999
A method for the labeling of gizzerosine (GZ), a biogenic amine found in fish meal, is described.... more A method for the labeling of gizzerosine (GZ), a biogenic amine found in fish meal, is described. The labeling procedure with 125 I using a water-soluble Bolton-Hunter reagent and a mild water-insoluble oxidant (Iodogen) reagent is rapid and reproducible. The 125 I-GZ hapten was demonstrated to be immunologically active in a radioimmunoassay developed with polyclonal antibodies to GZ absorbed with a histamine-Sepharose column. The curves were linear in the range of 0.0001 and 0.1 µg/mL. Samples of fish meal previously extracted of histamine with methanol and submitted to acid hydrolysis were contaminated with known amounts of GZ and submitted to the assay. The fish meal samples contaminated with GZ show a dose-response effect similar to the standard curve, and apparently the other component present in the sample did not interfere with the binding of the antibodies to 125 I-GZ. These data indicate the suitability of the radioimmunoassay to determine specifically GZ in fish meal.
The role of acrosin and antibodies to acrosin in gamete interactions
Journal of Reproductive Immunology, 1989
Sperm antigens relevant to human fertility : final report
Journal of Biological Chemistry, 2004
We describe here the structure of the hemocyanin from the Chilean gastropod Concholepas concholep... more We describe here the structure of the hemocyanin from the Chilean gastropod Concholepas concholepas (CCH), emphasizing some attributes that make it interesting among molluscan hemocyanins. CCH exhibits a predominant didecameric structure as revealed by electron microscopy and a size of 8 MDa by gel filtration, and, in contrast with other mollusc hemocyanins, its stabilization does not require additional Ca 2؉ and/or Mg 2؉ in the medium. Polyacrylamide gel electrophoresis studies, analyses by a MonoQ FPLC column, and Western blots with specific monoclonal antibodies showed that CCH is made by two subunits noncovalently linked, named CCH-A and CCH-B, with molecular masses of 405 and 350 kDa, respectively. Interestingly, one of the subunits undergoes changes within the macromolecule; we demonstrated that CCH-A has an autocleavage site that under reducing conditions is cleaved to yield two polypeptides, CCH-A1 (300 kDa) and CCH-A2 (108 kDa), whereas CCH-B remains unchanged. The CCH-A nick occurs at 4 °C, increases at 37 °C, and is not inhibited by the addition of protease inhibitors and/or divalent cations. Since the CCH structure is a heterodimer, we investigated whether subunits would be either intermingled, forming heterodecamers, or assembled as two homogeneous decamers. Light scattering and electron microscope studies of the in vitro reassociation of purified CCH subunits demonstrated that the sole addition of Mg 2؉ is needed for its reassembly into the native decameric molecule; no homodecamer reorganization was found with either CCH-A or CCH-B subunits alone. Our evidence showed that C. concholepas hemocyanin is an unusual example of heterodecameric organization.
Biochimica et biophysica acta, Dec 24, 2017
Hemocyanins have highly conserved copper-containing active sites that bind oxygen. However, struc... more Hemocyanins have highly conserved copper-containing active sites that bind oxygen. However, structural differences among the hemocyanins of various mollusks may affect their physicochemical properties. Here, we studied the oxygen-binding cooperativity and affinity of Concholepas concholepas hemocyanin (CCH) and its two isolated subunits over a wide range of temperatures and pH values. Considering the differences in the quaternary structures of CCH and keyhole limpet hemocyanin (KLH), we hypothesized that the heterodidecameric CCH has different oxygen-binding parameters than the homodidecameric KLH. A novel modification of the polarographic method was applied in which rat liver submitochondrial particles containing cytochrome c oxidase were introduced to totally deplete oxygen of the test solution using ascorbate as the electron donor. This method was both sensitive and reproducible. The results showed that CCH, like other hemocyanins, exhibits cooperativity, showing an inverse relat...
Product and Composition Containing a Concholepas Concholepas Hemocyanin (CCH) Subunit A, and a Method of Use Thereof
CD8p T Cells Are the Effectors of the Contact Dermatitis Induced by Urushiol in Mice and Are Regulated by CD4p T Cells
Int Arch Allergy Immunol, 1998
Novel hemocyanin from the Fissurella latimarginata exhibits an outstanding immunogenicity and non-specific immunomodulatory effects in a melanoma model
The Journal of Immunology, May 1, 2012
Product and composition containing a Concholepas concholepas hemocyanin (CCH) subunit, and a method of use thereof
Development of anti-human B blood group monoclonal antibodies suitable as a blood typing reagent
Hybridoma, 1994
An improved procedure for the generation of high-avidity anti-human B blood group monoclonal anti... more An improved procedure for the generation of high-avidity anti-human B blood group monoclonal antibodies (MAbs) was developed. One of them, termed 7A1-2, showed excellent qualities of titer, avidity, and intensity required for use as human B blood typing reagent. Hemagglutination inhibition studies with monosaccharides and oligosaccharides were carried out to determine the specificity of the MAb 7A1-2. These studies indicate that the antibody reacts with the immunodominant region of the antigen which is known to confer the serologic specificity of this blood group.
A Light-Induced Tryptophan-Riboflavin Binding: Biological Implications
Advances in Experimental Medicine and Biology, 1991
We review here the covalent photo-binding induced by visible light between the essential amino ac... more We review here the covalent photo-binding induced by visible light between the essential amino acid tryptophan and the vitamin riboflavin. We discuss the biological implications of this photoadduct in relation to the hepatotoxic and cytotoxic effect associated to parenteral nutrients and to culture media exposed to the action of light, respectively. We also analyze the formation of a photo-binding between riboflavin and the residues of tryptophan present in the proteins of the eye lens, a tissue which is permanently exposed to visible light.
Inhibitory effect of nordihydroguaiaretic acid and its tetra-acetylated derivative on respiration and growth of adenocarcinoma TA3 and its multiresistant variant TA3MTX-R
In vivo (Athens, Greece)
The effects of nordihydroguaiaretic acid (NDGA) and its tetraacetylated derivative (NDGATA) on th... more The effects of nordihydroguaiaretic acid (NDGA) and its tetraacetylated derivative (NDGATA) on the growth, oxygen consumption, adenosine 5'-triphosphate (ATP) level and viability of mouse mammary adenocarcinoma TA3 and its multiresistant variant TA3-MTX-R cell lines were determined. NDGA inhibited mitochondrial carbonyl cyanide m-chlorophenylhydrazone (CCCP)-stimulated oxygen consumption in mouse liver and tumor cells when glutamate plus malate or succinate was added as substrate. The effects were considerably weaker when respiration was supported by duroquinol, indicating that NDGA inhibited primarily mitochondrial electron flow located at some point before ubiquinone. Although NDGATA only inhibited the electron flow through complex I, it was more efficient and selective than NDGA because mouse liver mitochondria were significantly less sensitive to it than both tumor cell lines tested. NDGA and NDGATA inhibited mitochondrial ATP synthesis and, consequently, cell viability and ...
In vivo (Athens, Greece)
Multidrug resistance (MDR) continues being the major obstacle for successful anticancer chemother... more Multidrug resistance (MDR) continues being the major obstacle for successful anticancer chemotherapy. The action of nordihydroguaiaretic acid (NDGA) and its tetra-acetylated derivative (NDGATA) on TA3 mouse mammary adenocarcinoma cells and their ability to restore doxorubicin (DOX), cisplatin (CPT) and methotrexate (MTX) sensitivity of the multiresistant variant TA3-MTX-R was examined. Both NDGA and NDGATA synergistically enhanced the cytotoxicity of DOX, CPT and MTX, with a more evident effect in the TA3-MTX-R than in the TA3 cells. NDGATA was more effective than NDGA, as analyzed by the isobologram method. The combination of NDGATA and DOX also reduced the tumor growth rate in mice. Although it did not prolong the median survival time, 30% of mice showed no vestiges of tumor 200 days after implantation with either TA3 or TA3-MTX-R cells. Moreover, NDGA and NDGATA increased the accumulation of DOX and rhodamine (RHO) 123 in both cell lines. NDGA and NDGATA are able to chemosensitiz...
Preliminary Structural Characterization of Pacific Hagfish Immunoglobulin
Advances in Experimental Medicine and Biology, 1975
The immune capacities of primitive fishes of the class Agnatha, the lamprey and the hagfish, have... more The immune capacities of primitive fishes of the class Agnatha, the lamprey and the hagfish, have been under study for nearly a decade. Early results from Good and his collaborators suggested that lampreys, but not hagfish, possessed an adaptive immune response (1, 2). However, subsequent work of Linthicum and Hildemann (3) and Hildemann and Thoenes (4, 5) showed that hagfish (Eptatretus stoutii) could also respond specifically to certain immunogens and could reject allografts under appropriate conditions.
Síntesis y secreción del antígeno de superficie del virus de hepatitis B en cultivo de células animales
Biological research, 1992
Mammalian sperm acrosomes contain a trypsin-like protease called acrosin which causes limited and... more Mammalian sperm acrosomes contain a trypsin-like protease called acrosin which causes limited and specific hydrolysis of the extracellular matrix of the mammalian egg, the zona pellucida. Acrosin was localized on hamster, guinea-pig and human sperm using monoclonal and polyclonal antibodies to human acrosin labelled with colloidal gold. This was visualized directly with transmission electron microscopy, and with light and scanning microscopy after silver enhancement of the colloidal gold probe. Four distinct labelling patterns were found during capacitation and the acrosome reaction in hamster and guinea-pig spermatozoa, and three patterns were found in human spermatozoa. In the hamster, acrosin was not detected on the inner acrosomal surface after the completion of the acrosome reaction, thus correlating with the observation that hamster spermatozoa lose the ability to penetrate the zona after the acrosome reaction. With guinea-pig and human spermatozoa, acrosin was still detected ...
Developmental & Comparative Immunology, 1981
Photochemistry and Photobiology, 2008
The anaerobic phototransformation of tyrosine under visible light sensitized by riboflavin is rep... more The anaerobic phototransformation of tyrosine under visible light sensitized by riboflavin is reported. The cytotoxicity of the anaerobic photoproducts on in vitro-cultured myeloid mouse tumoral cells was demonstrated. A radical mechanism is proposed. Dityrosine was identified as one of the main anaerobic photoproducts by using absorption, emission and 'H-NMR spectra.
Photochemistry and Photobiology, 1999
The effect of the photoproducts of indole-3-acetic acid sensitized by riboflavin on nonirradiated... more The effect of the photoproducts of indole-3-acetic acid sensitized by riboflavin on nonirradiated human HL-60 and murine NS0/2 tumor cells was studied. Severe damage with a dose-response effect was observed on both cell types. The effect was greater than that previously described for the tryptophan riboflavin photoproducts. Electron microscopy studies and flow cytometry analysis of DNA fragmentation allowed us to conclude that the photoproducts studied in this work induce cell death by an apoptotic mechanism.
Journal of Reproductive Immunology, 2007
Females in numerous rodent species engage in communal nesting and breeding, meaning that they sha... more Females in numerous rodent species engage in communal nesting and breeding, meaning that they share a nest to rear their young together. One potential benefit to communally nesting mothers is that infants improve their immunocompetence. Thus, suckling from two or more females might provide newborns with a more diverse array of antibodies and defensive cells. As a first step toward testing the immunocompetence hypothesis, we assessed whether female degus (Octodon degus), a communally nesting and breeding caviomorph rodent, transfer immunoglobulins to their young through the yolk sac or placenta while in the uterus and, during lactation, through milk. With this aim, adult degu females were immunized with four antigens, including two mollusk hemocyanins from Concholepas and Megathura (CCH and KLH, respectively), porcine thyroglobulin and tetanus toxoid. Specific antibodies against the experimental antigens were used to track the origin of antibodies in the young. To establish the presence of specific antibodies of IgG and IgA isotypes in sera and milk of animals, an indirect enzyme-linked immunosorbent assay (ELISA) was developed. Degu females produced specific antibodies against antigens not found in their natural environment, and mothers were able to transfer the induced antibodies to their litters during pregnancy (IgG) and during lactation (IgA). However, we recorded only limited evidence of degu offspring acquiring antibodies from lactating mothers other than their own, giving little support to the increased immunocompetence hypothesis.
Journal of Agricultural and Food Chemistry, 1999
A method for the labeling of gizzerosine (GZ), a biogenic amine found in fish meal, is described.... more A method for the labeling of gizzerosine (GZ), a biogenic amine found in fish meal, is described. The labeling procedure with 125 I using a water-soluble Bolton-Hunter reagent and a mild water-insoluble oxidant (Iodogen) reagent is rapid and reproducible. The 125 I-GZ hapten was demonstrated to be immunologically active in a radioimmunoassay developed with polyclonal antibodies to GZ absorbed with a histamine-Sepharose column. The curves were linear in the range of 0.0001 and 0.1 µg/mL. Samples of fish meal previously extracted of histamine with methanol and submitted to acid hydrolysis were contaminated with known amounts of GZ and submitted to the assay. The fish meal samples contaminated with GZ show a dose-response effect similar to the standard curve, and apparently the other component present in the sample did not interfere with the binding of the antibodies to 125 I-GZ. These data indicate the suitability of the radioimmunoassay to determine specifically GZ in fish meal.
The role of acrosin and antibodies to acrosin in gamete interactions
Journal of Reproductive Immunology, 1989
Sperm antigens relevant to human fertility : final report
Journal of Biological Chemistry, 2004
We describe here the structure of the hemocyanin from the Chilean gastropod Concholepas concholep... more We describe here the structure of the hemocyanin from the Chilean gastropod Concholepas concholepas (CCH), emphasizing some attributes that make it interesting among molluscan hemocyanins. CCH exhibits a predominant didecameric structure as revealed by electron microscopy and a size of 8 MDa by gel filtration, and, in contrast with other mollusc hemocyanins, its stabilization does not require additional Ca 2؉ and/or Mg 2؉ in the medium. Polyacrylamide gel electrophoresis studies, analyses by a MonoQ FPLC column, and Western blots with specific monoclonal antibodies showed that CCH is made by two subunits noncovalently linked, named CCH-A and CCH-B, with molecular masses of 405 and 350 kDa, respectively. Interestingly, one of the subunits undergoes changes within the macromolecule; we demonstrated that CCH-A has an autocleavage site that under reducing conditions is cleaved to yield two polypeptides, CCH-A1 (300 kDa) and CCH-A2 (108 kDa), whereas CCH-B remains unchanged. The CCH-A nick occurs at 4 °C, increases at 37 °C, and is not inhibited by the addition of protease inhibitors and/or divalent cations. Since the CCH structure is a heterodimer, we investigated whether subunits would be either intermingled, forming heterodecamers, or assembled as two homogeneous decamers. Light scattering and electron microscope studies of the in vitro reassociation of purified CCH subunits demonstrated that the sole addition of Mg 2؉ is needed for its reassembly into the native decameric molecule; no homodecamer reorganization was found with either CCH-A or CCH-B subunits alone. Our evidence showed that C. concholepas hemocyanin is an unusual example of heterodecameric organization.
Biochimica et biophysica acta, Dec 24, 2017
Hemocyanins have highly conserved copper-containing active sites that bind oxygen. However, struc... more Hemocyanins have highly conserved copper-containing active sites that bind oxygen. However, structural differences among the hemocyanins of various mollusks may affect their physicochemical properties. Here, we studied the oxygen-binding cooperativity and affinity of Concholepas concholepas hemocyanin (CCH) and its two isolated subunits over a wide range of temperatures and pH values. Considering the differences in the quaternary structures of CCH and keyhole limpet hemocyanin (KLH), we hypothesized that the heterodidecameric CCH has different oxygen-binding parameters than the homodidecameric KLH. A novel modification of the polarographic method was applied in which rat liver submitochondrial particles containing cytochrome c oxidase were introduced to totally deplete oxygen of the test solution using ascorbate as the electron donor. This method was both sensitive and reproducible. The results showed that CCH, like other hemocyanins, exhibits cooperativity, showing an inverse relat...
Product and Composition Containing a Concholepas Concholepas Hemocyanin (CCH) Subunit A, and a Method of Use Thereof
CD8p T Cells Are the Effectors of the Contact Dermatitis Induced by Urushiol in Mice and Are Regulated by CD4p T Cells
Int Arch Allergy Immunol, 1998
Novel hemocyanin from the Fissurella latimarginata exhibits an outstanding immunogenicity and non-specific immunomodulatory effects in a melanoma model
The Journal of Immunology, May 1, 2012
Product and composition containing a Concholepas concholepas hemocyanin (CCH) subunit, and a method of use thereof
Development of anti-human B blood group monoclonal antibodies suitable as a blood typing reagent
Hybridoma, 1994
An improved procedure for the generation of high-avidity anti-human B blood group monoclonal anti... more An improved procedure for the generation of high-avidity anti-human B blood group monoclonal antibodies (MAbs) was developed. One of them, termed 7A1-2, showed excellent qualities of titer, avidity, and intensity required for use as human B blood typing reagent. Hemagglutination inhibition studies with monosaccharides and oligosaccharides were carried out to determine the specificity of the MAb 7A1-2. These studies indicate that the antibody reacts with the immunodominant region of the antigen which is known to confer the serologic specificity of this blood group.
A Light-Induced Tryptophan-Riboflavin Binding: Biological Implications
Advances in Experimental Medicine and Biology, 1991
We review here the covalent photo-binding induced by visible light between the essential amino ac... more We review here the covalent photo-binding induced by visible light between the essential amino acid tryptophan and the vitamin riboflavin. We discuss the biological implications of this photoadduct in relation to the hepatotoxic and cytotoxic effect associated to parenteral nutrients and to culture media exposed to the action of light, respectively. We also analyze the formation of a photo-binding between riboflavin and the residues of tryptophan present in the proteins of the eye lens, a tissue which is permanently exposed to visible light.
Inhibitory effect of nordihydroguaiaretic acid and its tetra-acetylated derivative on respiration and growth of adenocarcinoma TA3 and its multiresistant variant TA3MTX-R
In vivo (Athens, Greece)
The effects of nordihydroguaiaretic acid (NDGA) and its tetraacetylated derivative (NDGATA) on th... more The effects of nordihydroguaiaretic acid (NDGA) and its tetraacetylated derivative (NDGATA) on the growth, oxygen consumption, adenosine 5'-triphosphate (ATP) level and viability of mouse mammary adenocarcinoma TA3 and its multiresistant variant TA3-MTX-R cell lines were determined. NDGA inhibited mitochondrial carbonyl cyanide m-chlorophenylhydrazone (CCCP)-stimulated oxygen consumption in mouse liver and tumor cells when glutamate plus malate or succinate was added as substrate. The effects were considerably weaker when respiration was supported by duroquinol, indicating that NDGA inhibited primarily mitochondrial electron flow located at some point before ubiquinone. Although NDGATA only inhibited the electron flow through complex I, it was more efficient and selective than NDGA because mouse liver mitochondria were significantly less sensitive to it than both tumor cell lines tested. NDGA and NDGATA inhibited mitochondrial ATP synthesis and, consequently, cell viability and ...
In vivo (Athens, Greece)
Multidrug resistance (MDR) continues being the major obstacle for successful anticancer chemother... more Multidrug resistance (MDR) continues being the major obstacle for successful anticancer chemotherapy. The action of nordihydroguaiaretic acid (NDGA) and its tetra-acetylated derivative (NDGATA) on TA3 mouse mammary adenocarcinoma cells and their ability to restore doxorubicin (DOX), cisplatin (CPT) and methotrexate (MTX) sensitivity of the multiresistant variant TA3-MTX-R was examined. Both NDGA and NDGATA synergistically enhanced the cytotoxicity of DOX, CPT and MTX, with a more evident effect in the TA3-MTX-R than in the TA3 cells. NDGATA was more effective than NDGA, as analyzed by the isobologram method. The combination of NDGATA and DOX also reduced the tumor growth rate in mice. Although it did not prolong the median survival time, 30% of mice showed no vestiges of tumor 200 days after implantation with either TA3 or TA3-MTX-R cells. Moreover, NDGA and NDGATA increased the accumulation of DOX and rhodamine (RHO) 123 in both cell lines. NDGA and NDGATA are able to chemosensitiz...