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Renal disease with distinctive pathologic features developed in two young women who had placental site trophoblastic tumors. The renal abnormalities were manifested by proteinuria in both cases and by hematuria in one case; blood pressure was elevated in one of the patients. Pathologic examination of the kidneys showed distinctive glomerular abnormalities, characterized mainly by the presence of occlusive eosinophilic deposits in many of the glomerular capillary lumina, most of which stained for fibrinogen-related antigens and IgM by immunohistochemical techniques. Ultrastructural examination showed the deposits to consist mainly of granular material that contained packets of fibrillar material with the appearance of fibrin. The uterine tumors were composed of mononucleated and multinucleated cells with abundant cytoplasm that infiltrated between the muscle bundles of the myometrium; in both tumors there was prominent deposition of eosinophilic material that had the tinctorial properties of fibrin and that stained for fibrinogen and IgM in immunoperoxidase studies. The renal abnormalities disappeared after hysterectomy in one case; the other patient, who was receiving chemotherapy and had disseminated intravascular coagulation, died with leukopenia and sepsis. The clinical and pathologic features in these cases suggest that the renal abnormalities were related to the uterine tumors and that the production of immune complexes and/or the activation of intravascular coagulation by the tumors were pathogenetic mechanisms.  相似文献   
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Previous studies using conventional hetero- or isoantisera have indicated the involvement of class II (Ia) molecules in presentation of soluble by monocytes to inducer T lymphocytes, stimulation of inducer T cells in MLR, and recognition of Ia-bearing targets cells by cytotoxic T lymphocytes (CTL). The experience in using monoclonal anti-Ia reagents capable of blocking these phenomena in the human system is limited. Recently, however, we have characterized a lytic IgG2a monoclonal antibody, 9–49, that binds to functionally significant class II molecules. This antibody blocks (in the absence of complement): (1) specific binding of peripheral blood lymphocytes (PBL) to antigen-pulsed monocyte monolayers, (2) proliferation of PBL in response to soluble antigen (tetanus toxoid or mumps) or cell surface class II antigen stimulation in allogeneic or autologus MLR, (3) proliferation of cloned T4+ (inducer) lymphocyte cell lines to class II antigens, (4) generation of cytotoxic lymphocytes during allogenic MLR, and (5) recognition (and killing) of class II-bearing target cells by T4+ CTL clones. Proliferation and CTL activity of a T8+ clone is unaffected by the 9–49 antibody. These results indicate the usefulness of this monoclonal reagent in studies evaluating the functional role of Ia molecules in immune recognition phenomena.  相似文献   
5.
A monoclonal antibody specific for human alpha-fetoprotein (HAFP) was derived by the hybridoma technique. Spleen cells from mice immunized with pure HAFP were fused with a mouse myeloma cell line (P3×63-Ag-8) and an anti-HAFP secreting hybridoma cell line was cloned in soft agarose. The HAFP specific antibody was shown to be a monoclonal IgG1 subclass with extremely high avidity for HAFP.  相似文献   
6.
(LEW X BN)F1 cardiac allografts are rejected within 8 days in untreated LEW recipients. At the critical time point of 5 days after transplantation, the obviously rejecting grafts are enlarged and maximally infiltrated by host cells as shown by 111In-labeled lymphocyte tracer studies. However, when such hearts were retransplanted back to naive (LEW X BN)F1 secondary hosts, they survive indefinitely, showing that even late rejection is reversible in the absence of sustained host immunological drive. Attempts were then made to abrogate this advanced immune responsiveness using Cyclosporine (CsA). CsA therapy (15 mg/kg/day for 7 days) starting from day 5 produced indefinite graft survival, similar as if initiated at the time of operation. Addition of exogenous IL-2, which drives the proliferation of Tc, could not reverse this effect. Serial changes in phenotype of lymphocyte subpopulations infiltrating both acutely rejecting and indefinitely functioning cardiac allografts in unmodified and CsA treated hosts, respectively, were then studied. Ratio of Th:Tc/s cells in acutely rejecting grafts was 1.6 by day 3; it inverted abruptly to 0.7 by day 5-6, suggesting predominance of Tc/s during the later stages of allograft rejection. Similarly, treatment with CsA produced a transient depression of Th, with recovery of original Th:Tc/s ratio during the next 2-3 weeks. Adoptive transfer experiments were then performed to investigate the functional significance of these findings.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
7.
R Shaikh  M Linial  S Brown  A Sen  R Eisenman 《Virology》1979,92(2):463-481
The internal structural (gag) proteins of recombinant avian oncoviruses selected for the env gene of RAV-O (an endogenous chicken virus) and the src gene for PR-RSV-C were examined. Eight of ten clones of such recombinants were found to synthesize altered gag proteins. The gag proteins of one recombinant clone, PR-E-95c, were examined in more detail by gel electrophoresis and tryptic peptide mapping. These methods have allowed us to distinguish between the gag proteins of the two parental viruses and to determine from which virus the proteins of the recombinant virus were derived. PR-E-95c virions were found to contain p270, an electrophoretically distinguishable variant of p27 which is found in isolates of RAV-0. This recombinant virus also contains p12/15, which is electrophoretically indistinguishable from the p12/15 of both of the parental viruses. However, tryptic peptide analysis of p15 indicates that PR-E-95c has inherited PR-RSV-C-specific p15 sequences. These observations suggest that at least one cross-over has occurred between p15 and p27 in PR-E-95c. A striking difference between the proteins of PR-E-95c virus and those of the parental viruses is that the recombinant lacks polypeptides migrating in the position of p19 and contains two novel polypeptides termed p19α (MW 20,000) and p19β (MW 15,000). Both of these polypeptides are phosphorylated and share antigenic determinants and some tryptic peptides with parental p19. As determined by peptide analysis and radioimmunoassay, these p19-related proteins contain information from both parental viruses, suggesting that PR-E-95c has another cross-over within p19. The altered p19 proteins bind to viral RNA specifically and are associated with genomic RNA in the virion. Neither the stability nor the specific infectivity of the recombinant viruses appears to be significantly affected by the altered proteins.  相似文献   
8.
Temperature-sensitive mutants of reovirus type 3 are capable of interfering with the replication of wild-type reovirus type 3. The interfering activity correlated with the ability of pairs of mutants to complement at 39°: Pairs of noninterfering mutants (tsD × tsE) yielded efficient complementation (indexes of 10–50); pairs of interfering mutants (including members of groups ts A, B, G) did not produce significant complementation (indexes ~ 1). The ability of pairs of mutants to reassort at 39° generally followed a similar pattern. Thus interference is an important property of ts mutants of reovirus and needs to be considered when genetic interactions are being studied at 39°.  相似文献   
9.
The pathophysiologic basis for the exuberant intracellular growth of Mycobacterium avium complex (MAC) in AIDS patients is unclear but may relate to altered expression of modulatory cytokines. Interleukin (IL)-1, IL-6, and TNF- expression by monocytes from AIDS patients and healthy subjects (HS) stimulated with isogeneic MAC strains (SmT, smooth-transparent, virulent; SmD, smooth-domed, avirulent) was examined. Spontaneous cytokine production was not observed in patients with AIDS. MAC strains induced less IL-1 and IL-1 release in AIDS patients than HS (P < 0.05). The ratio of cell-associated to supernatant IL-1 also was increased in AIDS patients (P = 0.03). IL-1 mRNA expression paralleled protein release in either group of subjects. In both HS and AIDS patients, stimulation with SmD induced more IL-1 and TNF- release by monocytes compared to SmT. In AIDS patients, SmD also induced greater IL-6 release than SmT (P < 0.01). Alterations in monocyte expression and compartmentalization of the regulatory cytokines IL-1 and IL-6 may enhance bacterial replication and contribute to the patho-genesis of MAC infection in AIDS.  相似文献   
10.
Renal carcinoma developed in two or more members of nine families. Multiple generations were affected in five kindreds, and siblings in four. The median age at cancer diagnosis was a decade earlier than usual, and individual patients had bilateral or multifocal lesions; these are features of hereditary forms of diverse cancers. No patient had von Hippel-Lindau disease or other predisposing genetic syndromes. Karyotypes of the peripheral blood of nine persons showed no instance of a 3;8 chromosome translocation as recently reported in association with renal carcinoma in ten members of one family. The findings show that familial renal cancer is more common than previously reported in the literature.  相似文献   
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