Nodular glomerulosclerosis with deposition of monoclonal immunoglobulin heavy chains lacking C(H)1.
(1/68)
The objective of this study was to further characterize the clinical and immunopathologic features of heavy chain deposition disease (HCDD), a recently described entity. Four patients were diagnosed as having HCDD on a kidney biopsy. All presented with nodular glomerulosclerosis with deposition of gamma1 heavy chains lacking CH1 epitopes, but without light chains. Two different patterns were observed in the serum. First, patients 1 and 2 had a circulating monoclonal IgGlambda containing a short gamma1 heavy chain lacking CH1 epitopes, with an apparent molecular weight of 40 kD consistent with a complete CH1 deletion. Biosynthetic experiments also showed that the deleted heavy chain was produced in excess compared with light chains, and was secreted in vitro together with half Ig molecules, although these abnormal components were not detected by Western blot analysis of whole serum. Second, patients 3 and 4 had a circulating monoclonal IgG1lambda with an apparently normal, nondeleted heavy chain subunit, but serum fractionation followed by immunoblotting revealed an isolated monoclonal gamma1 chain lacking CH1 epitopes. These data strongly suggest that renal deposition of a CH1-deleted heavy chain circulating in low amounts in the serum as a free unassembled subunit is a major feature of HCDD. The CH1 deletion is most likely responsible for the premature secretion in blood of the heavy chain by a clone of plasma cells. (+info)
Gamma heavy chain disease in man: translation and partial purification of mRNA coding for the deleted protein.
(2/68)
Lymphoid cells obtained from the peripheral blood of a patient with heavy chain disease have been established in long-term culture. They continue to produce a protein antigenically identical to the deleted gamma3 heavy chain disease protein found in the patient's serum. The availability of the cell line has made it possible to analyze the mRNA coding for this protein. The primary in vitro translation product is 1500-2000 daltons larger than the polypeptide portion of the cytoplasmic or secreted protein and has methionine at the amino terminus. The mRNA sediments at 15.5 S on sucrose gradients and therefore appears to be smaller than the 17S message coding for normal-sized mouse gamma chains. It contains a base sequence that codes for a hydrophobic amino-terminal peptide not found in the cytoplasmic protein. There was no evidence for the synthesis of translatable light chain message by these cells. The present data suggest that this protein results from a primary somatic genetic event that gave rise to a cell product bearing a normal aminoterminus sensitive to limited proteolytic digestion. The serum protein thus appears to begin in the hinge region but, in fact, contains a normal heavy chain initiation site. (+info)
Gamma heavy chain disease simulating alpha chain disease.
(3/68)
A young Turkish girl presented with all the clinicopathological features of a digestive form of alpha chain disease. A gamma heavy chain disease protein, however, was found in her serum and also in the cells invading the intestinal mucosa and mesenteric lymph nodes. (+info)
Human heavy chain disease protein WIS: implications for the organization of immunoglobulin genes.
(4/68)
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. (+info)
A case of gamma 3 heavy chain disease with vacuolated plasma cells: a clinical, immunological, and ultrastructural study.
(5/68)
A patient with lambda Bence-Jones proteinuria, Waldenstrom's macroglobulinaemia, and Franklin's disease (gamma HCD), but without clinical evidence of a lymphoproliferative disorder, is presented. The serum contained two distinct immunoglobulin abnormalities: a monoclonal immunoglobulin M (IgM) of lambda type, and a protein fragment which was immunologically related to immunoglobulin G (IgG) and devoid of light chain activity. This gamma HCD protein belongs to the gamma 3 subclass with a molecular weight of approximately 60,000 daltons. The urine contained a Bence-Jones lambda protein as well as the gamma HCD fragment. The two paraproteins were probably secreted by two different malignant clones. Ultrastructural study revealed pathological vacuolated plasma cells of a sort that has hitherto been principally described in association with micron HCD. The mechanism of the intracellular storage of pathological immunoglobulins is discussed in the light of the ultrastructural study. (+info)
Gamma heavy chain disease: rapid, sustained response to cyclophosphamide and prednisone.
(6/68)
A patient, CAL, with gamma heavy chain disease is presented who has had a complete remission lasting over 2 yr with combination chemotherapy consisting of pulsatile cyclophosphamide and prednisone. The patient exhibited many features of an atuoimmune process including a vasculitis, low serum complement levels, a positive antiglobulin (Coombs) test, Raynaud's phenomenon, and keratoconjunctivitis sicca. The CAL paraprotein was found to have several previously undescribed characteristics. It reacted with antisera to Fd, Fab, and Fab', suggesting that most of the Fd portion of the molecule was intace. CAL protein consists of two polypeptide chains of molecular weight 49,000 covalently linked to form a dimer of 95,000 molecular weight. The covalent linkage suggests that the hinge region of this gamma heavy chain is intact. (+info)
Immunodiagnosis of alpha chain disease.
(7/68)
Since the early diagnosis of alpha chain disease (alphaCD)) is essential to successful treatment and to epidemiological studies, the available immunodiagnostic techniques were compared for their sensitivity, specificity and ease of performance on a panel of sixteen sera, comprising ten alphaCD sera and six control sera containing either IgA myeloma protein or high levels of polyclonal IgA. Immunoselection by immunoelectrophoresis into gel containing a specially developed anti-Fabalpha antiserum provided the most sensitive and specific detection system for alphaCD protein. The same technique using anti-light chain antiserum for immunoselection was also highly sensitive, but proved less specific, being prone to false positives with difficult IgA myeloma proteins. Somewhat less sensitive, but specific and simple to perform, was immunoelectrophoresis using an antiserum recognizing the conformational specificities of Fabalpha as well as those of the constant region of alpha chains. Immunoselection using the Ouchterlony or rocket techniques proved to be less sensitive and prone to false positives when some IgA myeloma sera were tested. (+info)
Celluar immunoglobulins in human gamma- and alpha-heavy chain diseases.
(8/68)
Proliferating cells from twenty-four patients with alpha- or gamma-heavy chain disease (HCD) were studied by direct immunofluorescence and in several cases by biosynthesis experiments with 14C-amino acid incorporation. In twenty-two patients, the cells contained the HCD proteins only and no light chain synthesis could be detected. Conversely, apparently non-secreted monotypic light chains were found in one case of gamma-HCD and one case of alpha-HCD. The proportion of proliferating cells containing cytoplasmic heavy chains, their appearance and the presence or not of surface heavy chains showed great variation from patient to patient. In some cases, the proliferation predominantly affected either plasma cells or lymphocytes whereas in others the disease seemed to correspond to a proliferation of HCD protein-bearing lymphocytes with persistent maturation into plasma cells. Large cell lymphomas supervening on alpha-HCD belonged to the same proliferating clone as the clone secreting the HCD protein, as shown by surface markers and biosynthesis experiments which demonstrated synthesis but no secretion of HCD proteins. In one patient with gamma-HCD, the cells carried surface gamma and delta chains. (+info)