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N L Warner

Publications and source records attributed to N L Warner.

At least 37 records · Page 2Linked to original sources
PubMed1983

Lym 7.3: new murine specificity defining third allele of the Ly 7 locus.

A new antigenic specificity, designated Lym 7.3, defines a third allele of the Ly 7 locus. The monoclonal antibody recognizing this determinant was produced by a hybridoma derived from immunization of B10.D2 Ign mice against a (BALB/c X NZB) F1 murine B lymphoma cell line (WEHI-5). Previously, we reported that another antibody (BD5-334.5) from this fusion reacted with an alloantigen similar or identical to the Ly 7.2 antigen originally described by McKenzie and coworkers. The Lym 7.3 specificity is qualitatively and quantitatively identical to the Lym 7.2 determinant in tissue distribution. Both antibodies react with a majority of splenocytes, peripheral blood lymphocytes, lymph node cells, and mitogen activated blasts from positive strains, but do not react with kidney, liver, or brain tissues by absorption analysis. B lymphocytes expressed significantly higher cell surface density of Lym 7.2 and Lym 7.3 than T lymphocytes. However, these antibodies clearly could be distinguished on the basis of inbred and congenic strain distribution. Three distinct phenotypes were presented: (1) Lym 7.2+ Lym 7.3+; (2) Lym 7.2+ Lym 7.3-; and (3) Lym 7.2- Lym 7.3-. Genetic studies suggested both specificities were encoded by a single locus.

Alleles↗
PubMed1983

Establishment of a continuous T cell line capable of suppressing anti-tumor immune responses in vivo.

This report describes the induction, phenotypic characteristics, and functional properties of a continuous suppressor T cell line. This cell line, UV1, is capable of suppressing anti-tumor immune responses both in vivo and in vitro. The UV1 cell line was derived from a T cell-enriched (nylon wool nonadherent, Ia-negative panned fraction) spleen cell population from a ultraviolet radiation-(UV) exposed BALB/c Wehi mouse. By using an in vivo functional assay designed to demonstrate tumor-specific UV-induced suppressor T lymphocyte (Ts cell) activity, it was found that UV1 cells were capable of rendering normal syngeneic mice susceptible to the growth of UV-induced regressor tumors. In addition to their suppressive activity in vivo, UV1 cells displayed in vitro suppressive activity by blocking the differentiation of cytotoxic T cells from the draining lymph nodes of UV-tumor immunized animals. By flow cytometric analysis it was determined that UV1 cells expressed a number of T lymphocyte differentiation antigens and did not express any detectable amounts of surface immunoglobulin, I-A or E/C antigens, Fc receptors, or macrophage antigens. These data suggest that the UV1 cell line may be representative of the UV-induced Ts cell population and provide a potential means for studying UV-induced immunoregulatory mechanisms in greater detail.

Animals↗
PubMed1983

Subpopulations of human natural killer cells defined by expression of the Leu-7 (HNK-1) and Leu-11 (NK-15) antigens.

The functional and phenotypic characteristics of cells in human peripheral blood that mediate "natural killer" (NK) cytolysis have been examined with the use of multiparameter flow cytometry analysis and cell sorting. Essentially, all lymphocytes expressing NK and ADCC activity reacted with the anti-Leu-11a monoclonal antibody. The Leu-11a antigen was expressed on cytotoxic large granular lymphocytes (LGL), neutrophils, and basophils, but was not present on B cells, mitogen-activated T lymphoblasts, or Leu-1+ and Leu 4+ resting T cells. Anti-Leu-11a antibody selectively inhibited the binding of FITC heat-aggregated IgG complexes to granulocytes and LGL, and it may recognize a type of Fc receptor on these cells. Two-color FACS cell sorting indicated the existence of four lymphocyte subsets defined by the expression of Leu-11a and Leu-7 antigens. The Leu-11a+, -7- cells were highly active in 4-hr NK assays with the use of 51Cr-labeled K562 as the target. In contrast, the Leu-11a-, -7+ cells demonstrated weak activity and the Leu-11a-, -7- cells demonstrated no activity. The function of the Leu 11a+, -7+ cells varied considerably among several individuals examined. Multiparameter analysis with the use of two-color flow cytometry was used to determine the relationship between the expression of these NK-associated antigens and T and B cell-associated markers. These data indicate that considerable heterogeneity exists within human peripheral lymphocytes with regard to cell phenotype and function, but that several defined cellular subsets can be clearly revealed by using multiparameter FACS analysis and sorting.

Antibodies, Monoclonal↗
PubMed1983

Anti-Leu-3/T4 antibodies react with cells of monocyte/macrophage and Langerhans lineage.

Anti-Leu-3a, anti-Leu-3b, OKT4, and anti-T4 murine monoclonal antibodies react with a membrane component expressed by mature peripheral blood helper T cells and certain thymocyte subsets. Using a variety of immunologic staining techniques, we have demonstrated the reactivity of these antibodies with other cell types. Normal and neoplastic cells of monocyte/macrophage lineage bear the Ia+/Leu-6-/Leu-3+ phenotype, whereas histiocytosis X cells bear the Ia+/Leu-6+/Leu-3+ phenotype. The Ia+/Leu-6- cells of malignant histiocytosis and the Ia+/Leu-6+ epidermal Langerhans cells were variably Leu-3+. Normal monocyte/macrophage reactivity with anti-Leu-3/T4 appears to be primarily intracytoplasmic, whereas on U937 monocyte tumor cells, marked membrane reactivity is also observed. These results strongly suggest that certain cells other than helper T cells and thymocytes can express and, at least in some cases, synthesize a component previously regarded as T-lineage specific.

Antibodies, Monoclonal↗
PubMed1982

Concomitant induction of the cell surface expression of Ia determinants and accessory cell function by a murine macrophage tumor cell line.

This study demonstrates that an uncharacterized soluble factor produced in concanavalin A-induced rat spleen cell suspensions has the capacity to induce the increased expression of cell surface H-2K and H-2D molecules and the expression of I-region gene products on murine monocyte-macrophage lineage tumors that are not Ia positive in the absence of the factor. In parallel with induction of serologically defined Ia specificities, Ia-induced WEHI-3 macrophage tumor cells are capable of providing accessory cell function in stimulating IL-2 production by T-T hybridomas that are activated in a major histocompatibility complex-restricted, antigen-dependent fashion. The uninduced Ia-negative WEHI-3 tumor cells do not trigger a comparable response in this assay system.

Animals↗
PubMed1982

Tumor immunity to murine plasma cell tumors. VII. Expression of H-2 and tumor antigens on Ig synthesis variants of MPC-11.

As a part of our continuing investigations directed toward defining the nature of the antigens on murine plasmacytomas (PCT), MPC-11 and two immunoglobulin (Ig) synthesis variants of this cell line were examined for H-2 and tumor-associated antigen (TAA) expression, and for the possible role of H-2 in the cytotoxic T lymphocyte response to TAA. The tumor lines studied were MPC-11 (an IgG2b producer), MPC-11,662 (a variant which produces only light chains), and NP.2 (a variant which produces neither Ig chain). Both H-2 expression, which was analyzed by flow cytometry and by cold target cell blocking of the activity of cytotoxic T lymphocytes (CTL) generated in allogeneic cultures, and TAA expression, which was analyzed by cold target cell blocking of the activity of tumor-specific CTL generated in syngeneic cultures, were found to be quantitatively similar on the three lines. When a possible association between H-2 and TAA expression was examined by testing the ability of anti H-2 sera to block tumor-specific CTL directed against MPC-11, no association between H-2 and TAA was detected. The results of these studies provide new information about H-2 and TAA expression on murine PCT. Furthermore, they suggest that changes in H-2 and TAA expression which have been reported to sometimes accompany loss of Ig synthesis may represent independent genetic, phenotypic, or metabolic variations, rather than alterations linked to the loss of Ig synthesis. In addition, these results, in agreement with out previous studies on MPC-11, support the concept that there is not an obligatory association of TAA with H-2 on the surface of murine PCT. Because these results differ from those reported in some other systems in which an association between H-2 and TAA on murine PCT was demonstrated, it must be emphasized that the TAA of PCT appear to be quite heterogeneous, and more investigations will be necessary in order to clearly define these antigen and the T-cell response to each of them.

Animals↗
PubMed1982

Cytotoxic T lymphocyte lines reactive against murine plasmacytoma antigens: dissociation of cytotoxicity and Lyt-2 expression.

The relationship between cell surface antigen expression and function in cytotoxic T cells directed against a non-H-2-restricted plasmacytoma antigen was examined using Lyt-2- variants of a continuous T cell line. This cytotoxic cell line originally had expressed Lyt-2 on all the cells as detected by flow microfluorometry, but after several months of culture, Lyt-2- variants spontaneously developed. Using cell sorting and limiting dilution cloning, Lyt-2- and Lyt-2+ cell lines were obtained, cultured and analyzed. These analyses indicated that such cytotoxic cells had similar activity regardless of Lyt-2 phenotype. This observation supports the concept that the Lyt-2 molecule is not obligatory for recognition and killing by cytotoxic T cells and emphasizes the need to clarify the precise relationship between cell surface phenotype and T cell function.

Animals↗
PubMed1982

Identification of distinct target-specific subsets of NK cells in peripheral blood of normal donors.

One major issue in studies on natural killer activities centers around the concept of heterogeneity of effector cells in the NK population. In this study Ficoll-Hypaque fractionated PBL from normal adult donors were used as effectors against a variety of tumor targets in in vitro chromium release assays with the goal of substantiation of the existence of NK subsets. Effectors with common or distinct specificities were demonstrated by the cold target inhibition assays as well as by immunoadsorption studies using tumor cell monolayers. In particular, a distinct subset of NK effectors, with the unique ability of killing a myeloma cell line (FRV), hitherto an NK-resistant tumor target, was demonstrated with the PBL of one normal donor (LP). Separation of this unique subpopulation based on differential light scatter property was achieved using flow cytometry (FACS III). The unique FRV killers were larger than the effectors which lyse K562 and they resemble the activated NK cells in the mouse system.

Adult↗
PubMed1982

Monoclonal antibodies against rat immunoglobulin kappa chains.

Monoclonal antibodies directed against rat kappa light chains have been generated by immunizing SJL/J mice with soluble rat immunoglobulin, followed by fusion of immune spleen cells with the P3-X63-Ag8 myeloma cell line. Monoclonal antibodies from three of these hybridoma cell lines, MAR 18.5, 80.2, and 103.6, have been extensively characterized. MAR 18.5, 80.2, and 103.6 antibodies are of the gamma 2a kappa isotype, and bind strongly to protein A, allowing easy purification. Monoclonal antibody from clone 18.5 binds equally well to Ig of both RI-1a and RI-1b allotypes, whereas 80.2 and 103.6 antibodies selectively bind to RI-1b. These monoclonal antibodies can be FITC conjugated for use as a second antibody in indirect immunofluorescence assays, or radiolabeled for use in radio immunoassays requiring a specific antirat kappa antibody. The antiallotype specific monoclonal antibodies also may be of use in the study of rat immunoglobulin genetics.

Alleles↗
PubMed1982

Lym 7.2: monoclonal antibody defining an alloantigen similar or identical to Ly 7.2.

Immunization of B10.D2 Ign mice against a (BALB/c X NZB)F1 murine B lymphoma cell line (WEHI-5) and subsequent fusion of immune spleen cells with a drug sensitive myeloma (P3 X 63-Ag8) has resulted in the generation of a series of hybridoma cell lines. One of these clones, BD5-334.5, secretes an antibody which reacts with a determinant, designated Lym 7.2, which demonstrates an identical tissue and strain distribution as the conventionally defined Ly 7.2 antigen. Furthermore, anti-Ly 7.2 alloantiserum significantly blocks reaction of the anti-Lym 7.2 monoclonal antibody with BALB/c splenocytes. Lym 7.2 is present on a majority of splenocytes, peripheral blood leukocytes, and lymph node cells. However, B cells express considerably higher cell surface density of this antigen than peripheral T lymphocytes. This antigen was not detected on erythrocytes, kidney, liver, or brain. Moreover, Lym 7.2 is present on approximately 15% of normal thymocytes, and 15% of bone marrow cells, and is expressed on cortisone resistant thymocytes. Quantitative flow cytometry analysis demonstrated that the antigen is present at approximately half the cell surface density on spleen cells from F1 mice between Lym 7.2 positive and Lym 7.2 negative mice, but on the same percentage of cells as Lym 7.2 positive inbred strains. Data from backcross analysis suggest that a single locus is encoding this antigen. Mitogen blasts, induced with PHA, ConA, and LPS, all express the Lym 7.2 marker.

Animals↗
PubMed1982

Antigen-specific. I region-restricted interactions in vitro between tumor cell lines and T cell hybridomas.

A series of H-2d B cell tumor lines and one monocytic tumor cell line were shown to be capable of I region-restricted antigen presentation to I-A-d- and I-Ed- restricted, antigen-specific cloned T cell hybridomas. For the most part, antigen presentation correlated with the present of Ia antigens on the presenting cells, although in a few interesting cases Ia-expression lines failed to present antigen. These T cell hybridomas, together with the B cell and to monocyte tumor cell lines, offer a unique set of tools to study the phenomenon of I region-restricted antigen presentation.

Animals↗
PubMed1982

Characterization and functional properties of tumor cell lines in accessory cell replacement assays.

This study reports the initial phenotypic and functional characterization of a series of cloned, murine, myelomonocytic tumors and their parent cell line WEHI-3, and a group of murine B lymphoma tumors. The tumor cell lines of the myelomonocytic lineage demonstrated the ability to reconstitute a macrophage-depleted, primary in vitro anti-SRBC PFC response, but only marginally enhanced an accessory cell-depleted, ova-primed, lymphocyte proliferation in vitro response. The B lymphoma tumors displayed exactly the reverse functional profile, being highly efficient in reconstitution of the proliferation response, but not supporting the SRBC PFC response. Detailed analysis of the cell surface phenotype of the various B lymphoma tumors used in this study show they display cell surface markers characteristic of normal B lymphocytes but are heterogeneous in their various stages of differential arrest. Future work will concentrate on the orchestration of Ia-mediated and soluble factor-mediated (IL 1) modalities of antigen-triggering of lymphocytes by these B lymphoma and myelomonocytic tumor cell lines.

Animals↗
PubMed1982

Radiation-induced augmentation of the response of A/J mice to SaI tumor cells.

Whole-body exposure of A/J mice to low doses (5-25 rads) of ionizing radiation immediately prior to the inoculation of 10(4) Sarcoma I (SaI) cells results in smaller tumors than are observed in sham-irradiated control animals. The irradiated group also contains a greater proportion of mice that fail to develop tumors or that demonstrate tumor regression. Low-dose augmentation is 1) less pronounced in recipients that have undergone splenectomy; 2) not evident in adult thymectomized-lethally irradiated-bone-marrow-restored (ATxXBM) animals, where the opposite effect is seen (eg, low-dose enhancement of tumor growth); and 3) abolished by the administration of normal syngeneic spleen cells unless the latter have been depleted of T cells. On this basis, a very radiosensitive T cell with suppressor activity is implicated in this phenomenon. Low-dose exposure at various times prior to tumor inoculation suggests that this cell regenerates in 5-10 days after irradiation.

Animals↗
PubMed1982

Heterogeneity of HLA-A,B, Ia-like, and melanoma-associated antigen expression by human melanoma cell lines analyzed with monoclonal antibodies and flow cytometry.

With the use of monoclonal antibodies, indirect immunofluorescence, and flow cytometry, human melanoma cell lines (Colo 38, M-16, and M-21) were examined for the quantitative level of expression of HLA-A,B antigens, Ia-like antigens, and two human melanoma-associated antigens (MAA) referred to as 280K and 94K MAAs. Each of the melanoma cell lines examined showed tremendous heterogeneity with regard to antigen expression. A detailed study of the heterogeneity of the four antigens listed revealed that variation in cell size could, in part, account for the large differences in antigen expression observed. Cell surface density of HLA-A,B antigens, Ia-like antigens, and the 280K and 94K MAAs remained relatively constant over a wide range of cell sizes that were examined, with the exception that small melanoma cells showed a slightly lower mean surface density of MAA expression than did large cells. A novel method was used to detect the expression of the two MAAs as a function of the Colo 38 cell cycle using dual-laser beam flow cytometry. The results of these experiments show that both the 280K MAA and the 94K MAA are differentially expressed during various stages of the cell cycle, with each antigen being maximally detected during G2 + M.

Antibodies, Monoclonal↗