Peter D. Gorevic

Mixed cryoglobulinemia: Clinical aspects and long-term follow-up of 40 patients☆

The clinical course of 40 patients with significant quantities of mixed cryoglobulins, but without lymphoproliferative, collagen-vascular or chronic infectious diseases, is presented. These cases comprise 51.3 percent of all mixed and 31.7 percent of all types of cryoglobulins evaluated by us over the period 1960--1978. A characteristic clinical syndrome, consisting of recurrent palpable purpura (100 percent), polyarthralgias (72.5 percent) and renal disease (55 percent), was seen. Biopsy specimens of skin lesions showed cutaneous vasculitis, and half had immune reactants in vessel walls. Seventy percent of patients had evidence of hepatic dysfunction, often subclinical, and more than 60 percent of those tested had serologic evidence of prior infection with hepatitis B virus. Hepatic lesions ranged from minimal triaditis to chronic active hepatitis and/or cirrhosis. All 22 patients in whom clinical renal disease developed had significant proteinuria; 63.6 percent had diastolic hypertension, 77.3 percent edema, 45.5 percent renal failure and 22.7 percent were nephrotic. Glomerular disease associated with deposition of immunoglobulin G, immunoglobulin M and complement, often with coexistent renal arteritis, was confirmed pathologically in 15 cases. All cryoglobulins had rheumatoid factor activity and consisted of IgM and polyclonal IgG; five also contained IgA. Thirteen had a monoclonal IgM kappa component. Serum protein electrophoresis was unremarkable or showed diffuse hyperglobulinemia. Striking depression of early complement components was noted but did not correlate well with the cryoprotein concentration, renal involvement or clinical course. Follow-up for periods up to 21 years from onset of symptoms revealed that renal involvement has a deleterious effect on prognosis. Postmorten examinations of nine patients demonstrated widespread vasculitis in addition to renal involvement. Preterminal infection was found in eight.

In vitro formation of amyloid fibrils from two synthetic peptides of different lengths homologous to alzheimer's disease β-protein

Two synthetic peptides corresponding to the reported 28-residue sequence of Alzheimers 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 Alzheimers 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.

Beta-2 microglobulin is an amyloidogenic protein in man.

Curvilinear fibrils with the tinctorial properties of amyloid were isolated from a patient with bone and joint involvement complicating chronic dialysis for renal disease. Subunit fractions of 24,000 and 12,000 mol wt were identified after gel filtration under dissociating conditions, the latter containing a significant amount of a dimer of the former. This was confirmed by Edman degradation of each fraction, which yielded the amino terminal sequence of normal human beta-2 microglobulin (B2M) to residues 20 and 30, respectively. The size of the subunit protein (12,000 mol wt) and the amino acid composition make it likely that intact B2M is a major constituent of the fibrils. B2M is thus another example of a low molecular weight serum protein, with a prominent beta-pleated sheet structure, that may adopt the fibrillar configuration of amyloid in certain pathologic states.

Ten to fourteen residue peptides of Alzheimer's disease protein are sufficient for amyloid fibril formation and its characteristic xray diffraction pattern

The molecular basis of fibril formation in Alzheimers disease was explored by electron micrographic and x-ray diffraction analysis of a series of synthetic peptides corresponding to portions of the amino acid sequence of beta protein and that of its putative precursor. A minimum 14 residue peptide was identified that formed typical amyloid fibrils under physiological conditions. Of these 14 residues, 10 were sufficient to give an identical 4.76 A and 10.6 A diffraction pattern as that recently described for isolated neurofibrillary tangles, amyloid plaque cores and leptomeningeal amyloid fibrils.

Abetimus sodium for renal flare in systemic lupus erythematosus: Results of a randomized, controlled phase III trial†

OBJECTIVE To investigate whether treatment with abetimus delays renal flare in patients with lupus nephritis. Secondary objectives included evaluation of the effect of abetimus on C3 levels, anti-double-stranded DNA (anti-dsDNA) antibody levels, use of high-dose corticosteroids and/or cyclophosphamide, and major systemic lupus erythematosus (SLE) flare. METHODS We conducted a randomized, placebo-controlled study of treatment with abetimus at 100 mg/week for up to 22 months in SLE patients. Three hundred seventeen patients with a history of renal flare and anti-dsDNA levels >15 IU/ml were randomized to a treatment group (158 abetimus, 159 placebo); 298 (94%) were enrolled in the intent-to-treat (ITT) population (145 abetimus, 153 placebo), based on the presence of high-affinity antibodies for the oligonucleotide epitope of abetimus at baseline screening. RESULTS Abetimus did not significantly prolong time to renal flare, time to initiation of high-dose corticosteroid and/or cyclophosphamide treatment, or time to major SLE flare. However, there were 25% fewer renal flares in the abetimus group compared with the placebo group (17 of 145 abetimus-treated patients [12%] versus 24 of 153 placebo-treated patients [16%]). Abetimus treatment decreased anti-dsDNA antibody levels (P < 0.0001), and reductions in anti-dsDNA levels were associated with increases in C3 levels (P < 0.0001). More patients in the abetimus group experienced > or =50% reductions in proteinuria at 1 year, compared with the placebo group (nominal P = 0.047). Trends toward reduced rates of renal flare and major SLE flare were noted in patients treated with abetimus who had impaired renal function at baseline. Treatment with abetimus for up to 22 months was well tolerated. CONCLUSION Abetimus at 100 mg/week significantly reduced anti-dsDNA antibody levels but did not significantly prolong time to renal flare when compared with placebo. Multiple positive trends in renal end points were observed in the abetimus treatment group.

Isolation and Partial Characterization of Neurofibrillary Tangles and Amyloid Plaque Core in Alzheimer's Disease: Immunohistological Studies

Fractions enriched in neurofibrillary tangles (NFT) and amyloid fibrils were isolated from the cerebral cortex of three cases of senile dementia of the Alzheimer type. Distilled water suspensions of these fractions were excluded from all pore size gels and resisted digestion with various proteolytic enzymes. Formic acid/chloroform treatment of each fraction resulted in the appearance of 4,000–6,000, 15,000–17,000 and 24,000 molecular weight proteins, with concomitant diminution in the amount of excluded material at the top of each gel. The 4,000–6,000 dalton band was best seen in fractions containing randomly arranged amyloid fibrils, and its amino acid composition resembled that of the recently reported “beta‘’ protein. A polyclonal antiserum to purified NFT reacted with tangles in neurons and in dystrophic neurites around plaques by immunoperoxidase staining. No reaction was obtained with cerebrovascular or plaque core amyloid immunohistologically, or with the 4–6 kD protein on immunoblots. Cross-reactivity with the neurofibrillary lesions occurring in Picks disease, progressive supranuclear palsy, postencephalitic Parkinsonism and dementia pugilistica was also seen. Specific binding of this antiserum to the double filamentous structure was confirmed by immunoelectron microscopy. Although the presence of “beta‘’ protein in both NFT and amyloid-containing fractions suggests that it may be an important constituent of both, cross-contamination cannot be excluded.

Systemic senile amyloidosis. Identification of a new prealbumin (transthyretin) variant in cardiac tissue: immunologic and biochemical similarity to one form of familial amyloidotic polyneuropathy.

Isolated amyloid fibrils from three cases of systemic senile amyloidosis (SSA) contained subunit proteins with molecular masses of 14 (10-20%), 10-12 (60-80%), and 5-6 kD (5-10%) when fractionated under reducing and dissociating conditions. This grouping was identical to that seen in SKO, a case of familial amyloidotic polyneuropathy (FAP) studied earlier. Amino acid sequencing confirmed that SSA subunit proteins were in fact prealbumin (transthyretin). Complete sequence analysis of one SSA preparation revealed the presence of a new variant Pa (TTr) molecule with a single amino acid substitution of isoleucine for valine at position 122. Further studies used an antiserum specific for SKO IV, a subunit protein of SKO previously shown to correspond to carboxy-terminal 78 residues (positions 49-127) of (TTr). Anti-SKO IV reacted with SSA in tissue at equivalent dilutions to anti-Pa (TTr) and with the 10-12-kD fraction of SSA on Western blots; reactivity was blocked by SKO IV, but not by Pa (TTr). SSA is a form of systemic amyloidosis caused by tissue deposition of Pa (TTr) and its fragments, with shared conformational or subunit antigenicity to at least one form of FAP. Identification of a new variant Pa (TTr) molecule in one case suggests further that SSA may be a genetically determined disease expressed late in life.

Tumoral amyloidosis of bone of beta2-microglobulin origin in association with long-term hemodialysis: A new type of amyloid disease

Amyloid lesions of bone are rare and limited almost exclusively to patients with amyloidosis secondary to plasma cell dyscrasias. The present report describes the cases of two patients receiving long-term hemodialysis (nine and 12 years) who had multiple lytic lesions of bone proved by biopsy to contain an unusual type of amyloid. Results of serum protein electrophoreses and immunoelectrophoreses, as well as bone marrow examinations, were normal. In both cases the amyloid displayed characteristic Congo red affinity and birefringence on polarized light microscopy that was inhibited by potassium permanganate treatment of sections prior to staining. Although this staining reaction was described previously exclusively in AA amyloid (i.e., the material associated with classic secondary amyloidosis), immunoperoxidase staining for AA protein in these cases was negative. Transmission electron microscopy revealed the amyloid fibrils to have unusual curvilinear configurations. Immunoperoxidase staining for beta 2-microglobulin (beta 2m) was positive in the amyloid lesions of both patients at the light microscopic level. Ultrastructural immunohistochemical studies for beta 2m, performed in one case, were positive. Both patients had markedly elevated serum beta 2m levels. By Ouchterlony immunodiffusion, purified beta 2m demonstrated partial identity with purified amyloid protein fractions and a serum constituent. Bone lesions composed of amyloid related to beta 2M probably represent a new subgroup of amyloid disease that may be linked to renal failure and long-term hemodialysis.

Amyloidosis Due to a Mutation of the Gelsolin Gene in an American Family with Lattice Corneal Dystrophy Type II

AMYLOID is a homogeneous, largely extracellular, proteinaceous material with a fibrillar ultrastructure and the property of green birefringence when stained with Congo red and viewed by polarizatio...

Lack of evidence for protein AA reactivity in amyloid deposits of lattice corneal dystrophy and amyloid corneal degeneration.

Amyloid fibrils occurring in primary and myeloma-associated (AL), secondary (AA), and certain neuropathic hereditary forms of systemic amyloidosis can be distinguished biochemically or immunohistologically as being composed of immunoglobulin light chain, protein AA, or prealbumin respectively. All types of systemic and several localized forms of amyloidosis contain amyloid P component (protein AP). We studied formalin-fixed tissue from eight cases of lattice corneal dystrophy by the immunoperoxidase method using antisera to proteins AA and AP, to normal serum prealbumin and prealbumin isolated from a case of hereditary amyloidosis, and to light-chain determinants; additional cases were examined by indirect immunofluorescence of fresh-frozen material. We found weak (1:10 dilution) staining with anti-AP, but no reactivity with other antisera. Congo red staining was resistant to pretreatment of sections with potassium permanganate, a characteristic of non-AA amyloid. Two-dimensional gels of solubilized proteins from frozen tissue from two cases of lattice corneal dystrophy resembled those obtained from normal human cornea. Western blots of two cases of polymorphous amyloid degeneration and solubilized protein from normal cornea did not react with radioactive iodine-labeled anti-AA or anti-AP with purified protein AP and unfixed protein AA amyloid tissue as controls. We were unable to corroborate the presence of protein AA in the amyloid deposits of lattice corneal dystrophy. Although staining with antiserum to protein AP was demonstrable, the molecular configuration of this protein in stromal deposits remains to be defined.