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T H The

Publications and source records attributed to T H The.

At least 181 records · Page 10Linked to original sources
PubMed1985

Isolation of highly purified lymphocyte subsets for functional studies by means of an indirect rosette technique.

An indirect rosette assay, utilizing ox erythrocytes (RBC) coupled with rabbit anti-mouse IgG and lymphocytes sensitized with monoclonal mouse antibodies against membrane markers, was used for purification of lymphocyte subsets that were functionally intact. Either peripheral blood mononuclear cells (PBMC) or T lymphocytes isolated by sheep RBC rosetting could be used as starting material for obtaining pure T-cell subsets (T4 or T8). The following steps of the method were evaluated: the procedure of coupling rabbit anti-mouse IgG to ox RBC via the CrCl3 method, the experimental conditions for specific rosetting, and the use of Percoll for the separation of rosettes from the non-rosetting cells. Under optimal experimental conditions the recovery of positively selected cells was 45-55% of the cells originally present in the PBMC. The purity of these cells reached a value of more than 95%, whereas the contamination of the depleted fraction was less than 3%. The functional integrity, manifesting itself as proliferation after mitogen stimulation and as regulatory influences on in vitro Ig synthesis, appeared to be unimpaired. The described technique may be applied to the purification of various cell subpopulations for functional studies, provided monoclonal antibodies against membrane antigens are available.

Animals↗
PubMed1985

Cytomegalovirus early and late membrane antigens detected by antibodies in human convalescent sera.

Using indirect immunofluorescence and a panel of human convalescent-phase sera, we identified cytomegalovirus (CMV) early and late membrane antigens (CMV-EMA and CMV-LMA, respectively) as separate entities on the surfaces of viable CMV-infected fibroblasts starting at 6 to 12 and 36 to 48 h postinoculation, respectively. For expression of CMV-EMA and CMV-LMA, infectious virus and active protein synthesis were required, whereas the expression of CMV-LMA, in addition, required viral DNA synthesis. Our data suggest that CMV-EMA and CMV-LMA form an individual set of CMV antigens that are different from intracellular CMV antigens and possibly (partly) different from the viral envelope.

Antibodies, Viral↗
PubMed1985

Decreased nailfold capillary density in Raynaud's phenomenon: a reflection of immunologically mediated local and systemic vascular disease?

Nailfold capillary patterns were studied in 107 patients with Raynaud's phenomenon (RP), including patients wih (n = 39) and without (n = 68) connective tissue disease (CTD). Capillary density was decreased in patients with sclerodactyly, digital ulcers, tuft resorption, and telangiectasia, compared with patients without these symptoms. In addition, an inverse relationship was found between the severity of RP at first presentation (as graded by photoelectric plethysmography during cooling) and the capillary density in patients with CTD (r = -0.45; p less than 0.05). In the total group of patients nailfold capillary density was inversely related to organ system involvement (r = -0.52; p less than 0.01). Decreased nailfold capillary density was observed, in particular, in patients with oesophageal hypomotility and in patients with chest x-rays compatible with interstitial fibrosis. As to factors supposedly involved in the pathogenesis of vascular changes in CTD, the presence of autoantibodies, increased levels of circulating immune complexes, and increased levels of acute phase reactants were all associated with a decreased number of nailfold capillaries. We conclude that loss of nailfold capillaries as observed by microscopy is a reflection of local and systemic vascular disease.

Adult↗
PubMed1985

Neuroendocrine differentiation antigen on human lung carcinoma and Kulchitski cells.

In the normal lung, a subset of cells with a histological appearance consistent with that of Kulchitski cells are the only lung cells reacting with a monoclonal antibody (MOC-1) raised against a human small cell lung carcinoma-derived cell line. Outside the lung, a subset of normal endocrine cells (in the adrenal, thyroid, ovary, and pancreas) as well as neural cells (brain and peripheral Schwann cells) also express the antigen detected by MOC-1 (named MOC-1-related antigen). Some of these positively reacting cells are ectodermally derived, whereas others are of proven endodermal origin, indicating that the MOC-1-related antigen is not a cell lineage-specific antigen. Instead, the common expression of the antigen by cells with a neural, endocrine, or neuroendocrine function suggests that the antigen related to a neuroendocrine differentiation state of these cells. The presence of the MOC-1-related antigen on several non-lung tumors mostly paralleled its normal tissue distribution, indicating that the antigen is generally retained upon malignant transformation. In lung carcinoma, the antigen proves to be present on almost all small cell carcinomas tested. In addition, adenocarcinoma and mixed adenosquamous carcinoma could also express the antigen, whereas pure squamous cell carcinoma generally did not. This finding will be discussed in relation to a proposed "common stem cell" histogenesis of lung carcinoma.

APUD Cells↗
PubMed1985

Maintenance of cytomegalovirus (CMV) latency and host immune responses of long term renal allograft survivors. I. Prolonged suppression of in vitro lymphocyte responses against CMV infected fibroblasts related to previous secondary CMV infection.

Cytomegalovirus (CMV) specific humoral and cellular immunity was investigated in 16 renal allograft recipients with long term graft survival (26-122 months) who were shown to be CMV seropositive before transplantation. Results were compared with healthy individuals with latent CMV infections. Recipients (n = 9) who experienced a symptomatic secondary CMV infection shortly after transplantation (less than 6 months), showed a prolonged but finally temporary suppression of their in vitro lymphocyte memory responses against CMV infected fibroblasts (CMV-FF; median SI: 1.9), a persistence of high antibody titres against intracellular CMV antigens and most of them also had antibodies against CMV membrane antigens (CMV MA). In contrast the recipients (n = 7) who could maintain their CMV in latency after transplantation, had lower antibody titres and their in vitro memory lymphocyte responses against CMV-FF (median SI: 9.3) were comparable to those of the healthy controls (median SI: 11.6). The memory lymphocyte responses against purified CMV virions were depressed in both recipient groups. These results suggest that cellular immunity against CMV infected target cells constitute an important mechanism in maintaining CMV in latency after allografting.

Adult↗
PubMed1985

Pneumatosis intestinalis in patients after cadaveric kidney transplantation: possible relationship with an active cytomegalovirus infection.

Four patients are presented with pneumatosis intestinalis following kidney transplantation, all with severe cytomegalovirus (CMV) infection. Two patients had a primary infection and two patients had CMV reactivation. One patient died because of disseminated CMV infection. Two patients had concomitantly an active, non-obstructive duodenal ulcer. In a control population of 17 patients who suffered from a duodenal ulcer post-transplant without any evidence of CMV infection, we could not demonstrate pneumatosis intestinalis. We suggest a possible relationship between pneumatosis intestinalis and active CMV infection. The possible mechanisms responsible for this relationship are discussed.

Adult↗
PubMed1985

Recovery of T cell subsets after autologous bone marrow transplantation is mainly due to proliferation of mature T cells in the graft.

In 22 patients with malignancies, treated with high-dose chemoradiotherapy and autologous bone marrow transplantation (BMT), peripheral blood T cell subsets and functions were studied. In ten cytomegalovirus (CMV)-negative patients, CD4+ and CD8+ T cells (representing T cells of the helper/inducer phenotype and T cells of the suppressor/cytotoxic phenotype, respectively), recovered slowly and simultaneously. In 12 CMV-positive patients, however, CD8+ T cells recovered more rapidly than CD4+ T cells and rose to increased counts. No T cells with an immature phenotype (CD1+, OKT6+) were observed. Lymphocyte stimulation by herpes simplex virus infected fibroblasts (and by CMV-infected fibroblasts in CMV-positive patients) in contrast remained high and even increased after BMT in both groups. These data indicate that T cell recovery after autologous BMT is mainly due to proliferation of mature T cells present in the BM graft and not to generation of new T cells from T cell precursors.

Antibodies, Viral↗
PubMed1985

Maintenance of cytomegalovirus (CMV) latency and host immune responses of long term renal allograft survivors. II. Secondary CMV infections associated with impaired in vitro proliferative responses to mitogens, allogeneic lymphocytes and CMV infected cells.

The relationship between secondary cytomegalovirus (CMV) infections and host general cellular immunocompetence was investigated in 16 renal allograft recipients with minimal immunosuppressive treatment and excellent renal function. Results were compared with 19 CMV seropositive healthy controls. Significantly impaired immune responses were detected in the subgroup of nine recipients who experience at least 2 years before a secondary CMV infection. Their in vitro lymphocyte reactivity (LR) tests to phytohaemagglutinin (PHA, P = 0.01), pokeweed mitogen (PWM, P less than 0.05), microbial antigens (P less than 0.001) and to pooled allogeneic stimulator lymphocytes in the MLC test (P = 0.02) were lower than the controls. The MLC responses, however, increased with graft survival time (r = 0.8810, P = 0.01). This was positively correlated with the virus specific cellular immunity measurable by the LR responses to CMV infected target cells (r = 0.8333, P = 0.02). In contrast, long term renal allograft survivors who maintained their CMV infection in latency after transplantation (n = 7) showed normal responses to PWM, pooled lymphocytes and CMV infected target cells, whereas the responses to PHA and to bacterial antigens were less severely impaired (P less than 0.05 and P less than 0.001, respectively). This study of long term renal allograft survivors shows that a secondary CMV infection has a long lasting negative effect on immunity especially against alloantigens and CMV infected targets. However, in the data presented here it would be as acceptable to suggest that the patients are consistently relapsing with CMV because they initially had poor immune response and not vice versa.

Antigens↗
PubMed1985

Characterization of three new variant type cell lines derived from small cell carcinoma of the lung.

Three new, well growing cell lines (GLC-1, GLC-2, and GLC-3) have been established from small cell lung carcinoma (SCLC) and characterized. A subclone (GLC-1-M13) markedly different from its parent line GLC-1 was also isolated and characterized. Cytogenetic analysis of the cell lines revealed deletions in the short arm of chromosome 3 as a most consistent chromosomal aberration. The deleted region was not identical in all metaphases, 3p(21-23) being the shortest region of overlap. Despite their SCLC origin GLC-1, GLC-2, and GLC-3 do not show pronounced SCLC differentiation features. Neurosecretory granula were very rare (GLC-1) or completely absent (GLC-2 and GLC-3), whereas the SCLC-related enzyme and hormone markers L-3,4-dihydroxyphenylalanine decarboxylase, neuron-specific enolase, creatine kinase BB, and bombesin-like immunoreactivity were variably expressed. Although the subclone GLC-1-M13 was derived from the poorly differentiated GLC-1, it behaved according to the above criteria as a differentiated "classic" SCLC cell line. When assessed with specific monoclonal antibodies the different cell lines appeared to express different subsets of intermediate filament proteins, indicative for different stages and directions of differentiation: "undifferentiated" (GLC-1 and GLC-2); "neural tissue related" (GLC-2); "simple epithelium" related (GLC-1-M13); and a combination of simple and squamous epithelium related (GLC-3). We conclude that GLC-1, GLC-2, and GLC-3 represent dedifferentiated forms of SCLC, related to the recently described "variant" type of SCLC, whereas the clonal derivate GLC-1-M13 behaves like a differentiated "classic" SCLC cell line.

Carcinoma, Small Cell↗
PubMed1985

The effect of cytomegalovirus infection on T lymphocytes after allogeneic bone marrow transplantation.

The influence of cytomegalovirus (CMV) infection on peripheral T lymphocyte repopulation was studied in 59 bone marrow transplant (BMT) recipients who received either cyclosporin A (CyA) or methotrexate (MTX) as prophylaxis for acute graft-versus-host disease. We used monoclonal antibodies and single- or double-marker immunofluorescence for the quantitation of T4+, T8+ and HNK1+ T cell subpopulations. CMV infection was serologically diagnosed by an enzyme-linked immunosorbent assay (ELISA), and by viral cultures and histological studies. Among the 52 patients who were evaluable for CMV infection, one had a primary infection and 24 had CMV reactivation/reinfection after BMT. In the latter patients, increases to supranormal levels were observed in T8+ T cells and HNK1+ T cells, both in patients on CyA and in patients on MTX. Double-marker immunofluorescence revealed that the two markers were largely expressed by the same cells, which therefore had the T8+ HNK1+ phenotype. In addition, the very small subset of T4+ HNK+ T cells was slightly, but consistently, increased in the patients with CMV reactivation/reinfection. CMV infection did not influence the numbers of T4+ HNK1- and T8+ HNK1- T cells. The long-lasting presence of large numbers of T8+ HNK1+ T cells in patients who had CMV reactivation/reinfection suggests a continuing interaction between the virus and the immune system of its host.

Adolescent↗
PubMed1985

In vitro T-cell dependent B-cell activity in myasthenia gravis.

The in vitro T-cell dependent B-cell activity was analysed in 34 patients with myasthenia gravis and in 16 controls by culturing 1 X 10(6) peripheral blood lymphocytes for 8 days with or without pokeweed mitogen (PWM) and measuring the amounts of IgG and IgM released into the culture supernatant. Increased production of IgG in the unstimulated cultures was found in 20 patients, 8 of whom also produced increased amounts of IgM. Upon PWM stimulation the patients produced normal amounts of IgG. The IgM production, however, was decreased in the patient population compared to the controls. Only one of the controls produced more IgG than IgM, either unstimulated or during PWM stimulation. In contrast 10 patients produced more IgG than IgM in the unstimulated cultures and 15 patients did so during PWM stimulation. The 'spontaneous' production of immunoglobulins was not measurable before 4 days of culture and was not the result of in vivo activated B-cells. We suggest that the increased 'spontaneous' immunoglobulin production and the decreased production of IgM during PWM stimulation may be a result of abnormal T-cell activity. The abnormalities found were not related to disease activity, the presence of multiple autoantibodies in the serum, steroid therapy or previous thymectomy. Besides these abnormalities, patients not treated with immunosuppressive drugs also showed decreased PWM induced IgG synthesis.

Adult↗
PubMed1985

Quantitation of antibodies to nucleoribonucleoprotein by ELISA: relation between antibody levels and disease activity in patients with connective tissue disease.

We describe a solid-phase enzyme-linked immunosorbent assay (ELISA) for quantitation of antibodies to nucleoribonucleoprotein (nRNP/Sm). nRNP/Sm was purified from rabbit thymus acetone powder by immunoaffinity chromatography and characterized by counterimmunoelectrophoresis (CIE) and immunoblotting using sera with well-known specificities. The purified antigen was used in ELISA. Positive results in ELISA were obtained only in sera with anti-nRNP or anti-Sm specificity as determined in CIE. Levels of anti-nRNP/Sm as quantitated by ELISA were higher in the sera of patients with active connective tissue disease (n = 7) than in those with inactive disease (n = 6) (P less than 0.01). Differences in anti-nRNP/Sm levels were also found between patients with mildly active disease (n = 19) and those with active disease (P less than 0.01). Fluctuations of anti-nRNP/Sm levels related to disease activity were seen in longitudinal observation. Although anti-nRNP/Sm levels as quantitated by ELISA correlated with titres of antinuclear antibodies as determined by immunofluorescence (r = 0.46, P less than 0.05), quantitation of anti-nRNP/Sm by ELISA is superior since the assay is antigen-specific and its quantitation independent of titration-related inaccuracies.

Adult↗
PubMed1984

Immunoperoxidase staining on frozen tissue sections as a first screening assay in the preparation of monoclonal antibodies directed against small cell carcinoma of the lung.

To prepare monoclonal antibodies against small cell carcinoma of the lung (SCCL), we have used an SCCL-derived cell line as immunogen. A first screening of hybridoma supernatants was performed on frozen tissue sections of a biopsy with histologically proven SCCL involvement. Screening on tissue sections is a valuable technique, especially for the isolation of monoclonal antibodies directed against tumor antigens. A drawback of this procedure is that it is laborious. To circumvent this, we have reduced the number of supernatants to be screened by increasing the number of seeded hybridomas per well. Although this resulted in the growth of 5-20 hybridomas per well, among which there was always at least one that secreted antibodies against 'common antigens', clones that secreted specific antibodies could still be revealed by testing supernatants which were preabsorbed with thrombocytes. This has resulted in the isolation of 7 monoclonal antibodies directed against SCCL associated antigens.

Antibodies, Monoclonal↗
PubMed1984

Pneumatosis intestinalis in patients after cadaveric kidney transplantation. Possible relationship with an active cytomegalovirus infection.

Four patients are described with pneumatosis intestinalis following cadaveric kidney transplantation, all with severe cytomegalovirus (CMV) infection. Two patients had a primary infection and 2 patients had a reactivation of CMV. One patient died because of disseminated CMV infection. Multiple inclusion bodies were found at postmortem examination in lungs and liver, and at the site of the ulcers in the gastrointestinal tract. Two patients had, concomitantly, an active, nonobstructive duodenal ulcer. In a control population of 17 patients who suffered from a duodenal ulcer post-transplant without any evidence of CMV-infection, we could not demonstrate pneumatosis intestinalis. We suggest a possible causal relationship between pneumatosis intestinalis and active CMV infection. The mechanisms that could be responsible for this relationship are discussed.

Adult↗