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F S Ligler

Publications and source records attributed to F S Ligler.

69 records · Page 4Linked to original sources
PubMed1983

Extremely high levels of natural killer cells in angioimmunoblastic lymphadenopathy.

Analysis of peripheral blood leukocytes from a patient with angioimmunoblastic lymphadenopathy using monoclonal antibodies and the fluorescence-activated cell sorter showed an unusually high proportion of cells that were OKT10+OKM1+63D3-. Since a large proportion of the large granular lymphocytes associated with natural killing in humans bears this surface phenotype, both blood and lymph node cells were subsequently tested for cell-mediated cytotoxicity in natural killer (NK)-cell assays. Following chemotherapy, both cells bearing the NK surface phenotype and the NK cytotoxicity disappeared and a population of cells, bearing none of the typical lymphocyte or monocyte markers, became dominant. At this point the patient was diagnosed as having immunoblastic sarcoma and shortly thereafter succumbed to his disease. In the few cases where extremely high levels of NK activity have been reported, the tumor cells themselves have been responsible for cell-mediated cytotoxicity. In this case, the final tumor population had no NK activity. Thus either a subpopulation of cytotoxic tumor cells was destroyed by chemotherapy or the patient had expanded numbers of NK cells reacting against his tumor prior to therapy.

Antibodies, Monoclonal↗
PubMed1983

Quantitative monitoring of lymphoid malignancies. Application and findings in chronic lymphocytic leukemia.

The present study investigated the surface immunoglobulin (Ig) phenotypic pattern in 64 cases of chronic lymphocytic leukemia (CLL). The fluorescence activated cell sorter techniques were modified to provide sensitive and highly reproducible detection and quantification of the otherwise faint surface immunoglobulins on the cells in CLL. In over 98% of the cases of CLL, light chain of the surface Ig could be identified and measured. Serial measurements were shown to be highly reproducible. The phenotypic pattern and density identified on the surface of the circulating lymphocytes precisely reflected the findings in any given patient when other lymphoid tissue (bone marrow, lymph node or spleen) was sampled. Intraclonal heterogeneity detected by surface Ig was seen in some cases of CLL in spite of a relatively uniform morphology by other classical techniques. Three patterns of cell-to-cell variation were seen: 1) that of a non-Gaussian distribution of surface light Ig staining intensity 2) that of the presence of increased surface light Ig chain on a portion of the cells with a subpopulation of CLL cells showing an additional class of heavy chain, and 3) that of anisotropy where the surface Ig quantitatively did not correlate with cell size. Immunoglobulin phenotypic characterization of the cases of CLL was correlated with their clinical stage of disease activity. The distribution of surface light chain phenotype did not relate to any pattern of clinical stage of activity of the disease. By contrast, cases where the cells had a predominance of surface IgM were associated with a more advanced stage of CLL and a poorer clinical prognosis. When surface IgG was predominant, a lesser degree of clinical activity of disease was identified. The phenotypic pattern of the surface Ig on the lymphocytes in CLL mirrors the pattern of differentiation in the murine model of B-cell differentiation, and clinical aggressiveness appears to correlate with the character and degree of B-cell differentiation.

Animals↗
PubMed1983

Immunoglobulin phenotype on B cells correlates with clinical stage of chronic lymphocytic leukemia.

The present study examines the relative amounts of surface immunoglobulin (Ig) on lymphocytes obtained from 64 patients with chronic lymphocytic leukemia (CLL) and correlates these findings with the clinical stage of disease. Since the maturing B cell first expresses surface IgM, followed by IgD, and subsequently by IgG, IgA, or IgE, the surface Ig phenotype can be used as a marker of differentiation. Surface Ig was analyzed using the fluorescence-activated cell sorter under carefully controlled conditions. The cells from all patients with CLL were monoclonal with respect to light chain type. Those patients with IgM as the brightest heavy chain class (suggesting relatively immature B cells) had clinically advanced stages of CLL, whereas those with a predominance of IgG (suggesting more mature cells) have a lesser stage of CLL. Thus, the predominant Ig heavy chain class appears to correlate with clinical stage of CLL and provides a clue to the potential aggressiveness of the tumor.

B-Lymphocytes↗
PubMed1982

Activation of T and B lymphocytes in NZB mice.

Since NZB mice manifest evidence of intense B cell activation, the state of activation of their T cells was explored. Electron microscopic examination and automated laser light scatter analysis demonstrated the presence of many blast lymphocytes in the spleens of aging NZB mice but not in controls. Only 45% of these large cells were B cells by the criterion of stainable surface IgM. NZB T and B cells were separated using the fluorescence-activated cell sorter; cytographic analysis revealed that both T and B cell populations contained substantial numbers of blast cells. The data thus indicated that T cells, as well as B cells, undergo activation as autoimmunity develops in NZB mice.

Aging↗
PubMed1981

Acute lymphocytic leukemic transformation of chronic lymphocytic leukemia: substantiation by flow cytometry.

Acute leukemia, during the course of chronic lymphocytic leukemia, is a rare event and only a small fraction of such cases have been shown to be true transformations to acute lymphocytic leukemia. In one previous case, evidence suggested this was transformation of a single neoplastic clone. The present report describes the clinical and laboratory findings in a case of chronic lymphocytic leukemia in which an acute leukemic pattern evolved. The fluorescence-activated cell sorter provided the resolution needed to distinguish low numbers of surface immunoglobulins on the acute leukemic cells, verifying their identity as B lymphoblasts. Furthermore, a small population of large cells bearing the same light chain type as the acute leukemia cells were detected in the spleen 3 1/2 months before clinical or laboratory evidence of the onset of the acute leukemia.

B-Lymphocytes↗
PubMed1981

A monoclonal antibody that identifies human peripheral blood monocytes recognizes the accessory- cells required for mitogen-induced T lymphocyte proliferation.

These studies were carried out to evaluate the functional characteristics of the cells identified by a monoclonal anti-human mononuclear phagocyte (M phi) antibody, 63D3. This antibody reacts specifically with all human peripheral blood M phi and not with normal human peripheral blood T or B cells. By using the fluorescence-activated cell sorter, human peripheral blood mononuclear cells (PBM) were sorted into 63D3-positive and 63D3-negative populations. Cell volume analysis indicated that 63D3-negative cells were identical to the non-adherent cells (NAC) in PBM, whereas 63D3-positive cells had a bimodal size distribution comparable to glass-adherent cells (AC). Neither 63D3-negative cells nor NAC were able to proliferate in response to mitogenic stimulation, whereas co-culture with either mitomycin C-treated AC or 63D3-positive cells restored mitogen responsiveness. Thus, the 63D3-positive population contains the relevant accessory cell required for mitogen-induced human lymphocyte proliferation.

Animals↗
PubMed1980

The effects of protein extraction on the structure and filtration properties of renal basement membranes.

Basement membranes were isolated from rabbit kidney using the detergent N-dodecyl sarcosine. Treatment of the membranes with 6 M urea or 5% sodium dodecyl sulphate in the presence of reducing agent at 37 degrees C extracted approximately 50% of the protein. Amino acid analysis and polyacrylamide gel electrophoresis demonstrated that the residual proteins were collagenous and of molecular weight. Extracted membranes retained their continuity of structure and exhibited a matrix composed of fibrous and globular elements when examined by electron microscopy. When the filtration properties of the membranes were studied in vitro they showed an enhanced capacity to retain proteins. The results suggest that basement membranes contain a matrix of fibrous proteins, which is responsible for the sieving characteristics of the native membranes.

Amino Acids↗
PubMed1980

Analysis and detection of B cell neoplasms.

Cells from human B cell lymphomas were analyzed by means of the fluorescence-activated cell sorter (FACS) according to the amount of kappa or lambda immunoglobulins (Ig) on their surface. The crucial requirements for sensitive recognition of small numbers of tumor cells admixed in a normal population are described. Tumor cells were identified as an excess of cells bearing one light chain type ('clonal excess') at discrete levels of fluorescence intensity. Normal patterns of fluorescence staining are compared to those for tissues infiltrated with tumor. For B cell neoplasms with surface Ig of weak intensity, such as chronic lymphocytic leukemia, as few as 1% of the tumor cells admixed with normal cells could be detected; the bright surface fluorescence of cells from lymphoma permitted their recognition when only 0.1% of the tumor cells were present. FACS analysis was carried out on the peripheral blood of a series of patients with B cell lymphoma whose blood was normal by classic cytologic and cytochemical analysis. Nevertheless, circulating tumor cells were recognized in the majority of cases, suggesting that 'subclinical leukemia' is a common finding in B cell lymphomas.

B-Lymphocytes↗
PubMed1979

An immunologic approach for the detection of tumor cells in the peripheral blood of patients with malignant lymphoma; implications for the diagnosis of minimal disease.

Lymphocytes were isolated from infiltrated lymph nodes and blood of eight patients with malignant lymphocytic lymphoma. All patients had normal numbers of circulating lymphocytes with normal morphology. None of the patients had serum paraproteins. The isolated lymphocytes from patients and controls were stained with affinity purified antibody specific for kappa- or lambda-light chains and analyzed by using a fluorescence activated cell sorter. Cells from infiltrated nodes stained for only one light chain type at high levels of fluorescence intensity. An increase in the number of brightly stained cells bearing the light chain type found in the involved node was readily detected in the peripheral blood of all but one of the patients with lymphoma. Similar changes in the ratio of kappa+- to lambda+-cells were not observed in 41 samples from nomral individuals and patients with other diseases.

Cell Transformation, Neoplastic↗
PubMed1978

Blocking of primary in vitro antibody responses to thymus-independent and thymus-dependent antigens with antiserum specific for IgM or IgD.

The effect of anti-mu and anti-delta on the primary in vitro IgM response of murine splenocytes to thymus-dependent (trinitrophenylated erythrocytes) and thymus-independent (trinitrophenylated brucella) forms of trinitrophenyl was studied. The results indicate that either anti-mu or anti-delta can block the response of adult splenocytes to the thymus-dependent antigen. The thymus-dependent responses of neonatal splenocytes that bear a low concentration of IgD were also abrogated by treatment with anti-delta. In contrast, anti-mu, but not anti-delta, blocked the response of adult splenocytes to the thymus-independent antigen used. These results indicate that both IgM and IgD are receptors required for triggering cells by a thymus-dependent antigen but that only IgM receptors are required for triggering by the thymus-independent antigen used.

Animals↗
PubMed1978

Inactivation of antigen-responsive clones with antisera specific for IgM or IgD.

The present study examines the isotype of cell surface immunoglobulins involved in triggering a response to thymus-dependent and thymus-independent antigens. Antibodies to immunoglobulin isotypes were used to block the in vitro interaction of receptor IgD and IgM with antigen. The results indicate that both IgD and IgM are necessary to trigger a response to TNP-SRBC but that only IgM is required for responsiveness to TNP-Brucella. Limiting dilution studies indicate that the inhibition of the immune response by antibody occurs at the level of precursor activation and suggest that there is no effect of antibody on subsequent proliferation of the daughter cells.

Animals↗
PubMed1977

B-cell tolerance. IV. Differential role of surface IgM and IgD in determining tolerance susceptibility of murine B cells.

During ontogeny IgD appears later than IgM on splenocytes of neonatal mice (1) and at a time when mice develop a markedly increased immune responsiveness (2). Based on these observations, it was suggested that IgD serves as a "triggering" isotype for induction of immune responses, whereas surface IgM functions as a tolerizing receptor (3). To test this hypothesis, the susceptibility of adult splenocytes (which are predominantly mu(+)delta(+)[4-6]) and neonatal splenocytes (which bear predominantly IgM [mup(+); 1, 4-6]) to tolerance induction were compared. The results indicate that neonatal splenic B cells responsive to thymus dependent (TD) antigens are exquisitely susceptible to tolerance induction compared with those from adult mice (7-9). However, cells from both adult and neonatal mice were highly susceptible to tolerance induction when thymus independent (TI) antigen was used as immunogen (8). These results suggest that the major precursor for the TD response is a mu(+)delta(+)-cell which appears late in ontogeny and is resistant to tolerance induction and that the mup(+)-cell is the major precursor for the TI response and is highly susceptible to tolerance induction. Other differences between responders for TI and TD antigens have been described previously (10-12). To test this concept, adult splenocytes were treated with papain under conditions in which IgD, but not five other surface molecules, was removed (13). Such treated splenocytes were shown to be markedly susceptible to tolerance induction, resembling TD responders from neonatal animals. This experiment was interpreted as indicating that IgD confers resistance to tolerance induction on mu(+)delta(+)-cells. To prove this interpretation, it is necessary to show that specific removal of IgD with anti-delta also results in increased susceptibility to tolerance induction and that treatment with anti-mu does not have a similar effect. In the present studies, we have removed surface IgM or IgD by antibody-induced capping and assessed the tolerance susceptibility of the treated cells. Our results demonstrate that removal of IgD, but no IgM, from TD responders increases their susceptibility to tolerance induction.

B-Lymphocytes↗
PubMed1977

A new method for the isolation of renal basement membranes.

A method is described for the isolation of basement membranes from rabbit renal cortex in which the detergent N-lauroyl sarcosine is used as the disruptive agent. The isolated membranes have been compared with membranes prepared using ultrasonication and they were comparable both in terms of purity and gross chemical composition. Glomerular and tubular basement membranes were isolated by first separating glomeruli from tubules by density gradient centrifugation followed by detergent treatment of the separated tissues. The detergent method has the advantage that the basement membranes retained their native structure to a large degree, whereas sonicated membranes were severely fragmented. Collagen fibres were a significant contaminant in both preparations and were revealed more clearly by negative staining than by examination of thin sections. Studies with the detergent-treated membrane revealed that a few proteins, which seemed to be membrane components, were extracted with 1 M NaCl and that these proteins were lost from the basement membranes during sonication used in the conventional isolation procedure.

Amino Acids↗
PubMedDate not supplied

Assay development for a portable fiberoptic biosensor.

The fiberoptic biosensor with tapered optical probes has been developed to perform rapid and sensitive fluoroimmunoassays. A number of assays for biologic analytes were developed using a laboratory breadboard device that employed a large, 514 nm argon ion laser. These assays, with limits of detection of 5-50 ng/ml for protein antigens, showed promise for clinical use because of their demonstrated lack of matrix effects from plasma, seru, or blood. However, such a large device was impractical for on-site diagnostics, so a new, portable, multichannel biosensor was developed. To test this new biosensor, which uses 635 nm laser diodes, the assays were converted to use the cyanine dye, Cy5. The detection antibodies were labeled with Cy5 and assays performed to detect the F1 antigen of Yersinia pestis and the protective antigen of Bacillus anthracis. The limit of detection was found to improve by a factor of 10 for each assay. The portable biosensor was then evaluated in a blind test containing F1 antigen spiked into 30 of 173 serum samples. One hundred percent detection was achieved for samples with 100 ng/ml or more F1 antigen, with a specificity of 88%.

Animals↗