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F Prelli

Publications and source records attributed to F Prelli.

At least 37 records · Page 2Linked to original sources

Degradation and deposition of amyloid AA fibrils are tissue specific.

The complete amino acid sequences of two related AA proteins (Mr 9700 and 5300) derived from thyroid tissue from a patient, NOR, with the autosomal recessive disease familial Mediterranean fever were determined. Heterogeneity found at position 52 indicates these proteins are fragments of two allelic or isotypic SAA precursor molecules similarly degraded at unusual sites and deposited in the thyroid. Degradation appears to be tissue and/or enzyme(s) specific since the carboxy terminus of both fragments is Ala-Ala and is different from other AA amyloid fibrils extracted from various tissues in different patients. Electron micrographic studies reveal these fragments retain the characteristics of native amyloid fibrils under physiological conditions even after exposure to dissociating agents.

Alleles

Hereditary cerebral hemorrhage with amyloidosis in patients of Dutch origin is related to Alzheimer disease.

Hereditary cerebral hemorrhage with amyloidosis in Dutch patients is an autosomal dominant form of vascular amyloidosis restricted to the leptomeninges and cerebral cortex. Clinically the disease is characterized by cerebral hemorrhages leading to an early death. Immunohistochemical studies of five patients revealed that the vascular amyloid deposits reacted intensely with an antiserum raised against a synthetic peptide homologous to the Alzheimer disease-related beta-protein. Silver stain-positive, "senile plaque-like" structures were also labeled by the antiserum, yet these lesions lacked the dense amyloid cores present in typical plaques of Alzheimer disease. No neurofibrillary tangles were present. Amyloid fibrils were purified from the leptomeningeal vessels of one patient who clinically had no signs of dementia. The protein had a molecular weight of approximately equal to 4000 and its partial amino acid sequence to position 21 showed homology to the beta-protein of Alzheimer disease and Down syndrome. These results suggest that hereditary cerebral hemorrhage with amyloidosis of Dutch origin is pathogenetically related to Alzheimer disease and support the concept that the initial amyloid deposition in this disorder occurs in the vessel walls before damaging the brain parenchyma. Thus, deposition of beta-protein in brain tissue seems to be related to a spectrum of diseases involving vascular syndromes, progressive dementia, or both.

Alzheimer Disease

In vitro formation of amyloid fibrils from two synthetic peptides of different lengths homologous to Alzheimer's disease beta-protein.

Two synthetic peptides corresponding to the reported 28-residue sequence of Alzheimer's Disease beta-protein (SP28) and to residues 12-28 (SP17) were used to form fibrils in vitro. Synthetic fibrils bound Congo Red and closely resembled amyloid fibrils isolated from leptomeninges and senile plaques of Alzheimer's brain by electron microscopy. A polyclonal antiserum to SP28 specifically decorated both synthetic and native amyloid by colloidal gold immunoelectron microscopy. Amyloid fibrils isolated from tissue were insoluble on SDS-Polyacrylamide gels, and tended to aggregate while synthetic amyloid fibrils were completely solubilized, releasing only monomers of SP28 and SP17. Anti-SP28 immunostained cerebrovascular and plaque core amyloid, but not neurofibrillary tangles, in tissue section. Western blot analysis showed that anti-SP28 reacted with a 4 kDa band released from amyloid core-enriched preparations and leptomeninges. By contrast, a 16 kDa band corresponding to the tetramer of beta-protein was not recognized. These data suggest that as little as a 17 residue sequence of beta-protein may be required to form fibrils and that the complete sequence of the 4 kDa beta-protein may be important in determining insolubility and the formation of intermediate size polymers.

Alzheimer Disease

Novel human light chain V kappa segment: serologic and structural analyses of the kappa III-like Bence Jones protein and IgG kappa light chain REE.

Immunochemical and sequence analyses of kappa light chain REE (Bence Jones protein REE and the light chain isolated from IgG kappa myeloma protein REE) revealed antigenic and structural features not previously described for human kappa-chains. Although closely related to proteins of the V kappa III subgroup, light chain REE is readily distinguished from light chains classified serologically as members of the kappa IIIa or kappa IIIb sub-subgroups. Light chains REE (Bence Jones protein REE and light chain REE) are identical in sequence and differ from kappa III proteins by at least 10 uncommon amino acid substitutions in the first three framework regions. Further, kappa-chain REE is unique by virtue of a four-residue deletion in the third complementarity-determining region. The deletion encompasses the three carboxyl-terminal residues in the V kappa-encoded segment and the first residue at the site of V-J recombination. Urine specimens from patient REE also contained a light chain fragment that lacked the first (amino-terminal) 85 residues of the native light chain but otherwise was identical in sequence to the light chain REE. The extensive amino acid differences and unique length of the V kappa segment in light chain REE indicate that this kappa-chain is the product of an unusual V kappa III gene or, alternatively, represents a rarely expressed and novel human V kappa gene.

Amino Acid Sequence

The primary structure of human tissue amyloid P component from a patient with primary idiopathic amyloidosis.

The amino acid sequence of human tissue amyloid P component (AP) extracted by a modified method from the spleen of a patient with primary idiopathic amyloidosis was determined. AP is a glycoprotein composed of a pair of noncovalently bound pentameric discs with a subunit size of 23-25 kDa. Each subunit consists of 204 residues, a single disulfide bridge linking Cys 36 to Cys 95, and a carbohydrate moiety attached to Asn 32. The precursor of AP is the serum amyloid protein (SAP). The primary structure of AP presented here differs from the amino acid sequence of SAP previously reported, but is identical to the amino acid sequence of mature SAP deduced from the nucleotide sequence of complementary DNA clones. It shares 52% homology with the amended sequence of human C-reactive protein, an acute phase protein, and 68% homology with the Syrian hamster "female protein," another acute phase protein whose response is modulated by sex steroids. AP/SAP, C-reactive protein, and female protein belong to a family of plasma proteins called pentraxins and their considerable sequence homology is probably the result of gene duplication. Neither the physiological function of AP nor its possible pathological role in amyloidosis are yet known.

Amino Acid Sequence

Human lambda light-chain constant region gene CMor lambda: the primary structure of lambda VI Bence Jones protein Mor.

Serologic, structural, and genetic analyses have shown that the constant (C) region of human kappa light chains is encoded by a single gene, whereas that of lambda chains is encoded by multiple genes. We have determined the complete C region amino acid sequence of two monoclonal lambda VI light chains, Bence Jones proteins Sut and Mor. The C region of lambda chains Sut and Mor consists of 105 residues, as is characteristic for human lambda light chains, of which 102 are identical in sequence. Protein Sut has the C region sequence associated with the C lambda isotype Mcg-, Kern-, Oz+ and represents a product of the C lambda 3 (Kern-, Oz+) gene. Protein Mor has a C region sequence associated with Mcg-, Kern-, and Oz- proteins but differs from protein Sut by the presence of three amino acid interchanges at positions 168, 176, and 194. These substitutions distinguish protein Mor from lambda chains encoded by the C lambda 1 (Mcg+), C lambda 2 (Kern-, Oz-), and C lambda 3 (Kern-, Oz+) genes and provide further evidence for polymorphism of the human C lambda genome. The gene encoding the C region sequence of lambda chain Mor is designated CMor lambda.

Amino Acid Sequence

Primary structure of an amyloid prealbumin variant in familial polyneuropathy of Jewish origin.

The complete amino acid sequence of three related amyloid proteins (Mr 14,000, 10,000, and 5,000) derived from tissues of a Jewish patient who suffered from a variant of familial polyneuropathic amyloidosis was determined. The protein, which contains 127 residues, is identical to a human serum prealbumin subunit. Only one amino acid substitution, glycine for threonine, was detected at position 49, where enzymatic cleavage occurred, yielding Mr 5,000 and 10,000 fragments which represent the amino terminus (residues 1-48) and carboxyl terminus (residues 49-127) of the molecule, respectively. Thus, a prealbumin variant and its fragments constitute the amyloid fibrils in a heredofamilial amyloidosis syndrome of dominant inheritance.

Amino Acid Sequence

Structural studies on an IgM-lambda pyroglobulin.

An IgM-lambda pyroglobulin from a patient with Waldenström's syndrome was studied. Heavy and light chains were separated and their N-terminal amino acid sequence determined. The heavy chain was unblocked and belonged to the VHIII subclass, and the light chain belonged to the lambda I subclass. Factors influencing pyroprecipitability were examined through experiments designed to study some of the physical and chemical properties of an IgM-lambda pyroglobulin. Pyroprecipitability was affected by pH, ionic strength, urea, and reducing agents, suggesting an involvement of noncovalent electrostatic interactions. It was also demonstrated through recombinant experiments that it is necessary to have covalently joined homologous heavy and light chains in pentameric form for pyroprecipitation to occur. Since neither heavy nor light chains had any unique structural features, the reasons for this property remain obscure but may reflect the result of conformational factors.

Amino Acid Sequence

A variant of prealbumin from amyloid fibrils in familial polyneuropathy of Jewish origin.

Amyloid fibrils were isolated from spleen and thyroid obtained at autopsy from one patient (S.K.O.) of Jewish origin with familial amyloidotic polyneuropathy. Gel filtration on Sephadex G100 after solubilization in 5 M guanidine HCl yielded three major components with 14,000, 9,000, and 5,000 mol wt, respectively. The two larger components shared antigenic determinants with human prealbumin. Amino acid analysis and amino terminal sequence studies revealed the 14,000-mol wt protein to be an intact prealbumin subunit. The 9,000-mol wt fragment obtained in highest yield encompassed the region from position 49-127 and the 5,000 mol wt fraction encompassed the amino terminal of prealbumin (position 1-48). An amino acid substitution (Gly/Thr) was detected at position 49, where enzymatic cleavage occurred. Thus, several prealbumin-derived fragments, predominantly the carboxyl end, constitute the amyloid fibrils in a heredofamilial amyloidosis syndrome of dominant inheritance.

Adult

Primary structure of human gamma 3 immunoglobulin deletion mutant: gamma 3 heavy-chain disease protein Wis.

The complete sequence of a gamma 3 heavy-chain disease (HCD) protein Wis is presented. The molecule is a dimer of a 289-residue chain linked by 12 disulfide bonds. Protein Wis has an unusual amino terminus, followed by a deletion of most of the VH domain. After a small stretch homologous to the VC joining region, there is a second deletion which ends at the beginning of the quadruplicated hinge. Two carbohydrate groups are linked to Asn-6 and -140. the molecule has an extra interchain disulfide bridge at position 7 in addition to the 11 normally present in the quadruplicated hinge. The previously noted homology to the gamma 1 heavy chain is striking; from positions 224 to 234, protein Wis resembles gamma 1 Nei [Ponstingl, H., & Hilschmann, N. (1976) Hoppe-Seyler's Z. Physiol. Chem. 357, 1571--1604] except for a serine which replaces Asn at position 227. The results, taken together with studies of other immunoglobulin heavy-chain deletion mutants, support the suggestion that the different domains and interdomain regions of human H chains are coded for by different gene segments and that the deleted proteins reflect alterations in the recombination of different genes and/or the splicing of heterogeneous nuclear messenger ribonucleic acid (hn mRNA).

Amino Acid Sequence

Human heavy chain disease protein WIS: implications for the organization of immunoglobulin genes.

Protein WIS is a human gamma3 heavy (H) chain disease immunoglobulin variant whose amino acid sequence is most readily interpreted by postulating that three residues of the amino terminus are followed by a deletion of most of the variable (VH) domain, which ends at the variable-constant (VC) joining region. Then there is a stretch of eight residues, three of which are unusual, while the other five have striking homology to the VC junction sequence. This is followed by a second deletion, which ends at the beginning of the quadruplicated hinge region. These findings are consistent with mutations resulting in deletions of most of the gene coding for the V region and CH1 domain followed by splicing at the VC joining region and at the hinge. These structural features fit well the notion of genetic discontinuity between V and C genes and also suggest similar mechanisms of excision and splicing in the interdomain regions of the C gene of the heavy chain.

Amino Acid Sequence

Mu heavy-chain disease--a defect in immunoglobulin assembly. Structural studies of the kappa chain.

Mu-chain protein GLI is a pentameric molecule with an amino-terminal deletion comprising 130 residues. The half-cysteine residue (position 140) which forms the H-L disulfide bridge in normal IgM is present. Instead of being joined to the L chain, it presumably exists as an additional inter-H-H disulfide bridge. The kappa Bence Jones protein is of normal size and present in two forms: as monomers and dimers. The carboxy-terminal half-cysteine of the monomer is bound to cysteine. Possible reasons for failure of assembly between mu and L chains are briefly discussed.

Amino Acid Sequence

The defect in mu heavy chain disease protein GLI.

Amino acid sequence studies of muHCD protein GLI reveal the absence of the amino terminal 130 residues. The molecule starts at Ala 131 and contains Cys 140, normally involved in the H-L disulfide bridges. Except for the deletion and presumably an extra H-H disulfide bridge involving Cys 140, the remainder of the mu-chain appears normal.

Amino Acid Sequence