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D T Weiss

Publications and source records attributed to D T Weiss.

34 records · Page 2Linked to original sources

Pathogenic potential of human monoclonal immunoglobulin light chains: relationship of in vitro aggregation to in vivo organ deposition.

The deposition of certain Bence Jones proteins as tubular casts, basement membrane precipitates, or amyloid fibrils results in the human light-chain-associated renal and systemic diseases--myeloma (cast) nephropathy, light-chain deposition disease, and immunocyte-derived (primary or AL) amyloidosis. To determine if light-chain nephrotoxicity or amyloidogenicity is related to the propensity of these components to form high molecular weight aggregates under physiological conditions, we used a size-exclusion chromatographic system to study 40 different Bence Jones proteins. Each samples was tested over a wide range of protein concentration in three different buffers varying in pH, osmolality, and the presence or absence of low concentrations of urea. Thirty-three of the 35 proteins found clinically and/or experimentally to form in vivo pathologic light-chain deposits were shown to undergo high-order self-association and form high molecular weight aggregates. In contrast, of five nonpathologic proteins, one showed polymerization under the chromatographic conditions used. The correlation between the in vivo results achieved by size-exclusion chromatography and that found in vivo provides (i) a rapid diagnostic method to identify potential nephrotoxic or amyloidogenic Bence Jones proteins and (ii) an experimental means to gain new insight into the physicochemical basis of light-chain aggregation and the treatment of those invariably fatal disorders associated with pathologic light-chain deposition.

Bence Jones Protein↗

Primary amyloidosis associated with a novel heavy-chain fragment (AH amyloidosis).

Primary or AL amyloidosis occurs in patients with monoclonal plasma cell-related disorders and is typically associated with the systemic deposition as amyloid fibrils of the light-chain portion of the immunoglobulin molecule. Recently, the discovery that heavy chains could be involved in amyloid formation led to the designation of this type of disease process as AH amyloidosis. We have now identified a second example of heavy chain-associated amyloidosis in a patient (MAD) who had a serum IgG monoclonal gammopathy and Bence Jones proteinuria. In this case, the renal and splenic amyloid deposits consisted solely of the VH-D-encoded portion of the heavy polypeptide chain, in contrast to the first case, where the amyloid contained an immunoglobulin component composed of the entire heavy-chain variable and third constant domains. In this respect, the chemical composition of the amyloid protein MAD differed not only from that of the first reported case of AH amyloidosis but from all other structurally abnormal components found in patients with heavy chain-associated disease. The discovery that certain forms of heavy chains, as well as light chains, can form amyloid provides further information on the chemical basis of amyloidogenicity and the diverse nature of this disease.

Amino Acid Sequence↗

Variable-region subgroup distribution among lambda-type immunoglobulins in normal human serum.

The distribution of the major VL subgroups (V lambda I, V lambda II, V lambda III, V lambda IV, V lambda VI, and V lambda VIII) among lambda-type immunoglobulins (Igs) in normal serum was determined by a sandwich enzyme-linked immunosorbent assay (ELISA) using a panel of murine anti-human V lambda-subgroup-specific monoclonal antibodies (MoAbs) and appropriate reference standard proteins. The mean concentration of lambda I, lambda II, lambda III, lambda IV, lambda VI, and lambda VIII Igs in serum specimens obtained from 23 adults was 2158, 162, 1958, 264, 225, and 169 micrograms/mL and represented 44, 3, 40, 5, 5, and 3% of the total Ig lambda population, respectively. The low percentage of lambda II Igs in normal serum was in marked contrast to the approximately 40% incidence of this V lambda subgroup found among lambda-type Bence Jones proteins and monoclonal serum Igs obtained from patients with multiple myeloma and AL amyloidosis, or approximately 60% in Waldenström's macroglobulinemia. The non-random expression of the V lambda II subgroup in these diseases implies a relationship between V lambda-gene usage and plasma cell, as well as certain types of lymphocytic dyscrasias.

Adult↗

Preferential expression of human lambda-light-chain variable-region subgroups in multiple myeloma, AL amyloidosis, and Waldenström's macroglobulinemia.

We have compared the distribution of lambda-light-chain variable-region (V lambda) subgroups among Ig lambda molecules found in the serum of normal individuals with that of monoclonal Ig lambda components obtained from patients with plasma cell and related immunoproliferative disorders. A panel of monoclonal antibodies specific for each of the major human V lambda subgroups--V lambda I, V lambda II, V lambda III, V lambda IV, V lambda VI, and V lambda VIII--was used in a highly sensitive enzyme-linked immunosorbent assay (ELISA) to quantitate each of these populations. The mean distribution of Ig lambda I, Ig lambda II, Ig lambda III, Ig lambda IV, Ig lambda VI, and Ig lambda VIII molecules in serum specimens collected from 20 normal adults was approximately 40, 3, 43, 5, 5, and 3% of the total Ig lambda population, respectively. In contrast, that of monoclonal IgG, IgA, and IgD proteins and Bence Jones proteins obtained from patients with multiple myeloma and related gammopathies (n = 196) was approximately 27, 28, 39, 5, 0, and 1%, respectively. The percentage of monoclonal Ig lambda II components found in individuals with AL lambda amyloidosis (n = 41) was comparably increased to that seen in multiple myeloma and was even higher in patients with Waldenström's macroglobulinemia (n = 16), in whom 63% of the IgM lambda proteins were of the V lambda II subgroup. Also evidenced were differences in the distribution of other V lambda subgroups in the disease states: Most striking was the predominance (41%) of the V lambda VI subgroup among monoclonal lambda chains obtained from patients with AL amyloidosis and that this subgroup was found exclusively on amyloidosis-associated proteins. No Ig lambda VI-type myeloma- or macroglobulinemia-related proteins were identified. The observed alterations in V lambda subgroup distribution among "pathologic" monoclonal Igs were attributed to the particular disease and not related to the heavy-chain class. Our finding that certain V lambda subgroups are nonstochastically expressed in lambda-type multiple myeloma, AL amyloidosis, and Waldenström's macroglobulinemia provides evidence for abnormal VL gene usage in these disorders and, thus, furnishes new insight into their pathogenesis.

Amyloid↗

Characterization of a novel interleukin-6 autocrine-dependent human plasma cell line.

A new human monoclonal plasma cell line, designated UTMC-2, was established from the pleural effusion of a patient with immunoglobulin (Ig)A kappa-related multiple myeloma. The cultured cells were Epstein-Barr virus-negative and exhibited the morphological and ultrastructural features characteristic of plasma cells. Immunohistochemical analyses revealed the presence of cytoplasmic IgA kappa as well as the plasma cell-associated surface antigens CD38 and CD56. Other B-cell markers, including CD10, CD19, CD20, and HLA-DR, were absent. The UTMC-2 cells were interleukin (IL)-6 responsive: Co-culture with IL-6 increased IgA kappa synthesis and cell proliferation in a dose-dependent manner. In contrast, an IL-6 antisense oligonucleotide had an opposite effect. Although the UTMC-2 cells expressed IL-6 mRNA (as demonstrated by reverse transcriptase-polymerase chain reaction (RT-PCR)) and contained IL-6, the concentration of this cytokine in cell culture supernatants was less than that detectable by the enzyme-linked immunosorbent assay (ELISA) employed (i.e. <3 pg/ml). Further, cell growth was not inhibited by polyclonal or monoclonal anti-IL-6 antibodies. Flow cytometric analysis revealed that IL-6 receptors present on the surface of the UTMC-2 cells were not saturated with endogenous IL-6. Taken together, these results indicate that, in this human plasma cell line, IL-6 functions uniquely in an intracellular autocrine fashion to enhance Ig synthesis and cell growth. In this respect, the UTMC-2 cells represent a novel resource for further study of the role of IL-6 in the pathogenesis of multiple myeloma.

ADP-ribosyl Cyclase↗

Novel immunization protocol and ELISA screening methods used to obtain and characterize monoclonal antibodies specific for human light chain variable-region subgroups.

We have developed a novel immunization protocol for the production of a panel of high-affinity murine monoclonal antibodies (MoAbs) that are specific for each of the major human kappa and lambda light chain variable-region (VL) subgroups. Mice were injected with heat-precipitated human Bence Jones proteins or VL-related fragments emulsified in monophosphoryl lipid A (MPL) and trehalose dimycolate (TDM) at two- to four-week intervals over a seven-month period. A unique direct capturing enzyme-linked immunosorbent assay (ELISA) employing biotinylated monoclonal light chains was designed to select optimally immunized animals for hybridoma preparation and to screen culture supernatants for high-affinity anti-VL MoAbs. These methods have led to the generation of MoAbs that by ELISA react specifically with each of the four V kappa subgroups--V kappa I, V kappa II, V kappa III, and V kappa IV or five V lambda subgroups--V lambda I, V lambda II/V, V lambda III, V lambda IV, and V lambda VI. These reagents have been used successfully to establish, on the basis of VL subgroup, the monoclonal nature of serum or urinary immunoglobulins as well as those found in the cytoplasm or on the cell surface of monoclonal plasma cell or B-lymphocyte populations, respectively. The availability of anti-VL subgroup-specific MoAbs will facilitate the immunodiagnosis and study of patients with multiple myeloma, AL amyloidosis, and related B-cell proliferative disorders.

Amyloidosis↗

Production and immunodiagnostic applications of antihuman light chain monoclonal antibodies.

Hybridomas producing antihuman light chain monoclonal antibodies (MoAbs) were derived from fusion of SP2/O mouse myeloma cells with splenic lymphocytes from mice repeatedly immunized with purified kappa- and lambda-type Bence Jones proteins representative of the major V kappa (V kappa I, V kappa II, V kappa III, V kappa IV) and V lambda (V lambda I, V lambda II/V, V lambda III, V lambda IV, V lambda VI) subgroups or gene families. Monoclonal antibodies were obtained that had specificity for constant-region (CL) determinants common to all kappa or lambda light chains (C kappa and C lambda, respectively) as well as for variable-region (VL) epitopes unique to each of the V kappa or V lambda subgroups. The capability of these reagents to recognize CL and VL determinants on monoclonal immunoglobulin (Ig) molecules was demonstrated in fluid-phase antigen-capturing enzyme-linked immunosorbent assay (ELISA), solid-phase ELISA, and immunoblotting. In addition, these antilight chain MoAbs were used to establish immunocytochemically the kappa or lambda type and VL-subgroup nature of light chains expressed by the cytoplasmic Ig of monoclonal plasma cell and surface Ig of B-lymphocyte populations, respectively. These antibodies facilitated the immunohistochemical detection and characterization of light-chain-associated amyloid (AL amyloid) and other types of light-chain-related tissue deposits. Furthermore, the anti-CL-specific MoAbs were used to measure serum and urinary Ig kappa and Ig lambda concentrations. Quantification of Bence Jones protein excretion, even in the presence of other urinary proteins, was possible using the highly sensitive anti-C kappa and anti-C lambda MoAbs reactive only with free light chains. The ability to identify and characterize, through the use of these antihuman light chain MoAbs, light-chain-related epitopes at the protein, cellular, and tissue level has clinical importance in the diagnosis and treatment of patients with monoclonal plasma cell and related B-cell immunoproliferative diseases.

Amyloidosis↗

Induction in mice of human light-chain-associated amyloidosis.

Primary (idiopathic) or multiple myeloma-associated amyloidosis is characterized by the deposition in tissue of monoclonal light chains or light-chain fragments (AL amyloidosis). In contrast to other types of amyloidosis, information regarding the pathogenesis of light-chain-related amyloid has heretofore been limited due to the lack of a suitable in vivo model. The authors report the successful experimental induction of human AL amyloid deposits. The repeated injection into mice of Bence Jones proteins obtained from two patients with AL amyloidosis produced the histopathologic lesions characteristic of this disease. Partial dehydration of animals before protein injection resulted in the acceleration of amyloid formation. The human proteins were deposited as amyloid within the mouse renal blood vessel walls and parenchymal tissue, as well as in other organs. The deposits were Congo red-positive, exhibited green birefringence, and had a fibrillar ultrastructure. As evidenced immunohistochemically, the experimentally induced amyloid deposits consisted of the injected human light chains, and in addition, contained mouse amyloid P component (AP); mouse immunoglobulin (Ig) or inflammatory-associated amyloid A protein was not detected. Extraction and characterization of the amyloid deposits found within the mouse kidney revealed the presence of a predominantly intact human light polypeptide chain. Mice injected in identical manner with a non-amyloid-associated Bence Jones protein had no or only rare amyloid deposits. The experimental mouse model provides a means to ascertain the amyloidogenic potential of human monoclonal light chains and to study further the pathogenesis of AL amyloidosis.

Amyloid↗

Nephrotoxic potential of Bence Jones proteins.

BACKGROUND: The renal manifestations of diseases associated with the production of monoclonal light chains--myeloma (cast) nephropathy, light-chain deposition disease, and amyloidosis AL--result from the deposition of certain Bence Jones proteins as tubular casts, basement-membrane precipitates, or fibrils, respectively. For unknown reasons, the severity of the renal manifestations of these diseases varies greatly from patient to patient. We employed an experimental in vivo model to determine the pathologic importance of various Bence Jones proteins. METHODS: Mice were injected intraperitoneally with 300 mg of Bence Jones protein from 40 patients with multiple myeloma or amyloidosis AL and killed 48 hours later. The mouse kidneys were examined by light and electron microscopy, and light-chain deposits were identified immunohistochemically with highly specific antihuman light-chain antiserum. RESULTS: Of the 40 different human Bence Jones proteins studied, 26 were deposited in the mouse kidneys predominantly as tubular casts, basement-membrane precipitates, or crystals; no light-chain deposits were detected in the kidneys of the mice that received the other 14 Bence Jones proteins. Of the 18 patients for whom renal tissue was available for study, the findings in 14 were comparable to those in the mice. Furthermore, the proteins obtained from 22 of the 27 patients whose serum creatinine concentrations equaled or exceeded 168 mumol per liter (1.9 mg per deciliter) were deposited in the mouse kidneys, whereas protein deposition occurred after the injection of proteins from only 4 of the 13 patients with serum creatinine concentrations below 168 mumol per liter. The repeated injection of Bence Jones proteins from two patients who had amyloidosis AL resulted in deposition of the protein in the mouse kidneys as amyloid. CONCLUSIONS: Particular Bence Jones proteins are primarily responsible for producing the distinctive types of protein deposition in renal tissue and the clinical manifestations that occur in patients with light-chain-associated diseases. This experimental model has potential value for the identification of nephrotoxic or amyloidogenic light chains.

Adult↗

Serologic and chemical differentiation of human lambda III light chain variable regions.

Human lambda L chains of a major V lambda subgroup, V lambda III, have been differentiated serologically and chemically into three V lambda III sub-subgroups designated V lambda IIIa, V lambda IIIb, and V lambda IIIc. Antisera prepared against lambda III Bence Jones proteins were obtained that recognized distinctive V lambda III-related epitopes expressed by monoclonal lambda III L chains. After appropriate absorption, these reagents were rendered specific for three distinct populations of lambda III proteins--lambda IIIa, lambda IIIb, and lambda IIIc. The antisera were used in comparative immunodiffusion analyses of 28 monoclonal lambda III L chains, 10 of which were classified as lambda IIIa, 4 as lambda IIIb, and 14 as lambda IIIc. The isotypic nature of the three lambda III sub-subgroups was demonstrated serologically through analyses of lambda-chains derived from the serum IgG molecules of normal individuals. The amino acid sequences of five serologically classified lambda III chains, which included members of the three V lambda III sub-subgroups, had been previously determined. This information, in addition to our establishment of the complete (or virtually complete) V region sequence of 15 and the partial sequence of eight other lambda IIIa, lambda IIIb, and lambda IIIc proteins, made it possible to correlate chemical data with serologic classification. Proteins within each of the three serologically-classified lambda III sub-subgroups typically possessed a high degree (approximately 83%) of intra-sub-subgroup sequence homology that included both framework and complementarity determining region residues. Furthermore, within the framework and complementarity determining regions, sub-subgroup-specific residues were identified. Taken together, these data reveal that the human V lambda III genome consists of (at least) three distinct V lambda IIIa, V lambda IIIb, and V lambda IIIc germline genes that encode for lambda IIIa, lambda IIIb, and lambda IIIc L chains, respectively.

Amino Acid Sequence↗

Immunoglobulin heavy-chain-associated amyloidosis.

Immunoglobulin- or multiple myeloma-associated amyloidosis has been distinguished by the tissue deposition of Congophilic, fibrillar protein consisting of light chains or light-chain fragments (AL amyloidosis). We now report the isolation and characterization of another form of immunoglobulin-associated amyloid obtained from a patient who had extensive systemic amyloidosis and in whom the amyloid deposits consisted not of light chains but rather of an unusual form of heavy chain. This component, isolated from splenic amyloid extracts, represented an internally deleted IgG1 heavy chain as evidenced by immunochemical, electrophoretic, and amino acid sequence analyses. A comparable immunoglobulin-related monoclonal protein, consisting only of IgG heavy chains, was present in the patient's urine. Based on serologic reactivity with a battery of anti-immunoglobulin antisera, these two immunoglobulin-related components were antigenically identical; however, when compared to normal IgG, both were deficient in Fc-associated gamma-chain determinants. The structural abnormality of the amyloid gamma-chain protein was further evidenced by SDS/PAGE and immuno-blotting analyses: An unusually low molecular mass of approximately 22 kDa was found for this material vs. the expected value of approximately 55 kDa for a normal gamma heavy chain. Despite the lack of certain Fc determinants, the amyloid and urinary heavy-chain proteins expressed the IgG1 subclass allotype marker G1m(a) located on the third constant region (CH3) domain of the internally deleted IgG1 heavy chains. That the amyloid protein contained an intact CH3 domain was established through amino acid sequence analyses of cyanogen bromide fragments and peptides generated by a lysine-specific protease. These studies also revealed that the gamma-chain amyloid protein contained the complete heavy-chain variable (VH) domain [including the diversity (DH) and joining (JH) segments] that was contiguous with the CH3 domain. The low molecular mass of the protein resulted from the total absence of the first (CH1), hinge, and second (CH2) heavy-chain constant regions. Such extensive CH deletions and the presence of a complete VH distinguish this amyloid-associated heavy chain from all other heretofore characterized gamma-heavy-chain disease proteins. This heavy-chain-related form of immunoglobulin-associated amyloidosis is tentatively designated AH amyloidosis.

Aged↗

Immunocytochemical detection of kappa and lambda light chain V region subgroups in human B-cell malignancies.

We have used a sensitive immunoperoxidase method and highly specific anti-light chain antisera to determine the light chain variable region (VL) subgroup nature of cytoplasmic (c) and cell surface (s) Ig expressed by human monoclonal plasma cells and B lymphocytes. The immunocytochemical characterization of cIg and sIg used antisera specific for the established kappa light chain V kappa subgroups (V kappa I, V kappa II, V kappa III, and V kappa IV) and the lambda light chain V lambda subgroups (V lambda I, V lambda II/V, V lambda IV, and V lambda VI). Studies were performed using cytospin preparations of bone marrow-, peripheral blood-, and lymph node-derived cells from patients with multiple myeloma, amyloidosis AL, and Waldenström's macroglobulinemia and with low-, mid-, and high-grade B-cell malignancies. The V kappa or V lambda subgroup of the cIg or sIg also could be identified after deparaffinization and enzyme treatment of formalin-fixed, paraffin-embedded specimens. For those patients who had monoclonal serum or urinary Igs, there was complete concordance between the VL subgroup of the secreted Ig and that of the cIg or sIg. The percentage distribution of V kappa or V lambda subgroups on the sIg of cells from patients with chronic lymphocytic leukemia (CLL) and other cytomorphologic types of B-cell malignancies differed from that found for kappa- or lambda-type Bence Jones proteins obtained from patients with multiple myeloma, amyloidosis AL, and Waldenström's macroglobulinemia. In contrast to the plasma cell and lymphocytoid plasma cell diseases, a relative predominance of certain VL subgroups, ie, V kappa IV, V lambda III, and V lambda IV, and the absence of the amyloid-associated V lambda VI subgroup were found in CLL and related diseases. The immunocytochemical techniques used make possible a rapid means to demonstrate B-cell monoclonality and provide further evidence for the selective expression of certain VL genes in human B-cell neoplasia.

Amyloidosis↗

Immunogenic and antigenic epitopes of Ig. XXV. Monoclonal antibodies that differentiate the Mcg+/Mcg- and Oz+/Oz- C region isotypes of human lambda L chains.

The C region of human lambda L chains is specified by multiple C lambda genes of which three--C lambda 1, C lambda 2, and C lambda 3--encode for the isotypes designated Mcg+, Kern- Oz-, and Kern- Oz+, respectively. The Mcg, Kern, and Oz factors have been characterized by sequence differences involving specific C lambda amino acid residues. They have also been recognized serologically by polyclonal antisera but, with rare exception, these reagents are no longer available. We have obtained two murine anti-human lambda-chain mAb, 14G1 and 14D1, that recognize antigenic determinants specific for the C lambda isotypes Mcg and Oz, respectively. These antisera have been used to classify as Mcg+/Mcg- or Oz+/Oz- monoclonal lambda-chains (Bence Jones proteins) and intact Ig lambda proteins. There was complete concordance between the chemical and serologic assignment of lambda-chains as Mcg+/Mcg- or as Oz+/Oz-; no single protein expressed both isotypes. There was no evident association between the C region isotype Mcg or Oz and the V region subgroup of the protein tested. However, our finding that four of seven amyloid-associated lambda VI Bence Jones proteins were Oz+ suggests a predominant expression of the C lambda 3 gene product among proteins of this uncommon V lambda subgroup.

Animals↗

Serologically defined V region subgroups of human lambda light chains.

The availability of numerous antisera prepared against lambda-type Bence Jones proteins and lambda chains of known amino acid sequence has led to the differentiation and classification of human lambda light chains into one of five V lambda subgroups. The five serologically defined subgroups, V lambda I, V lambda II, V lambda III, V lambda IV, and V lambda VI, correspond to the chemical classification that is based on sequence homologies in the first framework region (FR1). Proteins designated by sequence as lambda V react with specific anti-lambda II antisera and are thus included in the V lambda II subgroup classification. The isotypic nature of the five V lambda subgroups was evidenced through analyses of lambda-type light chains that were isolated from the IgG of normal individuals. Based on analyses of 116 Bence Jones proteins, the frequency of distribution of the lambda I, lambda II/V, lambda III, lambda IV, and lambda VI proteins in the normal lambda chain population is estimated to be 27%, 37%, 23%, 3%, and 10%, respectively. This distribution of V lambda subgroups was comparable to that found among 82 monoclonal Ig lambda proteins. Considerable V lambda intragroup antigenic heterogeneity was also apparent. At least two sub-subgroups were identified among each of the five major V lambda subgroups, implying the existence of multiple genes in the human V lambda genome. The V lambda classification of 54 Ig lambda proteins obtained from patients with primary or multiple myeloma-associated amyloidosis substantiated the preferential association of lambda VI light chains with amyloidosis AL and the predominance of the normally rare V lambda VI subgroup in this disease.

Amyloidosis↗