Search

Your search keyword '"Wortis, Henry H."' showing total 123 results
Start Over Author "Wortis, Henry H."
123 results on '"Wortis, Henry H."'

6. Uphold the nuclear weapons test moratorium

Author

King, Jonathan, primary, Chalfie, Martin, additional, Chomsky, Noam, additional, Cirincione, Joseph, additional, Decatur, Sean, additional, Franklin, Melissa, additional, Gerson, Joseph, additional, Goldenberg, David P., additional, Goldstein, Gary, additional, Hartung, William, additional, Helfand, Ira, additional, Holz, Daniel, additional, Kahn, Peter C., additional, Krimsky, Sheldon, additional, Loechler, Edward, additional, Moghadam, Val, additional, Newman, Stuart A., additional, Ozonoff, David, additional, Parthasarathi, Prasannan, additional, Phillips, William, additional, Politzer, H. David, additional, Redwine, Robert P., additional, Roberts, Richard J., additional, Robock, Alan, additional, Royer, Catherine Ann, additional, Scarlata, Suzanne, additional, Scarry, Elaine, additional, Smoot, George F., additional, Socolow, Robert, additional, Solomon, Susan, additional, Strominger, Andrew, additional, Sundberg, Eric J., additional, Sur, Mriganka, additional, Tegmark, Max, additional, Tierney, John F., additional, van der Ziel, Cornelia, additional, VanElzakker, Michael, additional, von Hippel, Frank N., additional, Wittner, Lawrence, additional, and Wortis, Henry H., additional

Published
2020
Full Text
View/download PDF

15. THE MAIL.

Author

Soliday, Elizabeth, Mueller, Lorin, Staub, Adrian, and Wortis, Henry H.

Subjects
SOCIAL science research, ACADEMIC fraud
Published
2023

18. Two New Isotype-Specific Switching Activities Detected for Ig Class Switching1

Author

Ma, Limei, Wortis, Henry H., and Kenter, Amy L.

Subjects
Recombination, Genetic, B-Lymphocytes, Mice, Inbred BALB C, Base Sequence, Immunoglobulin mu-Chains, Immunoglobulin gamma-Chains, Molecular Sequence Data, chemical and pharmacologic phenomena, Cell Transformation, Viral, Immunoglobulin alpha-Chains, Lymphocyte Activation, Immunoglobulin Class Switching, Article, Coculture Techniques, Clone Cells, Immunoglobulin Isotypes, Mice, Retroviridae, Cytidine Deaminase, Tumor Cells, Cultured, Animals, Immunoglobulin epsilon-Chains, Cell Line, Transformed, Plasmids
Abstract

Ig class switch recombination (CSR) occurs by an intrachromosomal deletional process between switch (S) regions in B cells. To facilitate the study of CSR, we derived a new B cell line, 1.B4.B6, which is uniquely capable of mu --gamma3, mu --epsilon, and mu --alpha, but not mu --gamma1 CSR at its endogenous loci. The 1.B4.B6 cell line was used in combination with plasmid-based isotype-specific S substrates in transient transfection assays to test for the presence of trans-acting switching activities. The 1.B4.B6 cell line supports mu --gamma3, but not mu --gamma1 recombination, on S substrates. In contrast, normal splenic B cells activated with LPS and IL-4 are capable of plasmid-based mu --gamma1 CSR and demonstrate that this S plasmid is active. Activation-induced deaminase (AID) was used as a marker to identify existing B cell lines as possible candidates for supporting CSR. The M12 and A20 cell lines were identified as AID positive and, following activation with CD40L and other activators, were found to differentially support mu --epsilon and mu --alpha plasmid-based CSR. These studies provide evidence for two new switching activities for mu --gamma1 and mu --epsilon CSR, which are distinct from mu --gamma3 and mu --alpha switching activities previously described. AID is expressed in all the B cell lines capable of CSR, but cannot account for the isotype specificity defined by the S plasmid assay. These results are consistent with a model in which isotype-specific switching factors are either isotype-specific recombinases or DNA binding proteins with sequence specificity for S DNA.

Published
2002

20. Fraud Allegations

Author

Wortis, Henry H., Huber, Brigitte T., and Woodland, Robert T.

Published
1988

21. Babesia microti Primarily Invades Mature Erythrocytes in Mice

Author

Borggraefe, Ingo, primary, Yuan, Jie, additional, Telford, Sam R., additional, Menon, Sanjay, additional, Hunter, Rouette, additional, Shah, Sohela, additional, Spielman, Andrew, additional, Gelfand, Jeffrey A., additional, Wortis, Henry H., additional, and Vannier, Edouard, additional

Published
2006
Full Text
View/download PDF

39. CD22 attenuates calcium signaling by potentiating plasma membrane calcium-ATPase activity.

Author

Jie Chen, McLean, Paul A., Neel, Benjamin G., Okunade, Gbolahan, Shull, Gary E., and Wortis, Henry H.

Subjects
CELL membranes, CALCIUM, ANTIGENS, B cells, IMMUNOGLOBULINS, CYTOPLASM, TYROSINE
Abstract

Binding of antigen to the B cell receptor induces a calcium response, which is required for proliferation and antibody production. CD22, a B cell surface protein, inhibits this signal through mechanisms that have been obscure. We report here that CD22 augments calcium efflux after B cell receptor crosslinking. Inhibition of plasma membrane calcium-ATPase (PMCA) attenuated these effects, as did disruption by homologous recombination of the gene encoding PMCA4a and PMCA4b. PMCA coimmunoprecipitated with CD22 in an activation-dependent way. CD22 cytoplasmic tyrosine residues were required for association with PMCA and enhancement of calcium efflux. Moreover, CD22 regulation of efflux and the calcium response required the tyrosine phosphatase SHP-1. Thus, SHP-1 and PMCA provide a mechanism by which CD22, a tissue-specific negative regulator, can affect calcium responses. [ABSTRACT FROM AUTHOR]

Published
2004
Full Text
View/download PDF

44. CD4, CD8 γ/δ cells from normal mice respond to a syngeneic B cell lymphoma and can induce its differentiation.

Author

Sperling, Anne I. and Wortis, Henry H.

Abstract

Lymph nodes and spleens from normal unimmunized mice contain small numbers of CD3, CD4, CD8 (double negative, DN) T cells. Of these, approximately one-third express the marker Ly-5(8220) in a form previously seen only on normal B cells and a population of DN T cells found in mice genetically prone to develop autolmmunity. DN T cells proliferate when co-cultured with a syngeneic surface Ig lymphoma, CH12. After one cycle of stimulation with CH12 almost all of the responding CD3 DN cells express Ly-5(B220), suggesting that it is an activation marker for some DN T cells. The CH12 responding population also contains cells with two other phenotypes, Thy-1, CD4, CD8, Ly-5(B220), sIgM, CD3 and Thy-i, CD4, CD8, Ly-5(B220), sIgM, CD3. The Ly-5(B220), CD3 population is no longer found after repeated stimulation. While the relationship between these three populations is unknown, DN I cells can proliferate in the absence of CD4 or CD8 cells and therefore their proliferation is not dependent on the presence of other T cells or lymphokines produced by CD4 or CD8 T cells. Anti-CD3 Immunoprecipitation of CH12-respondlng cells reveals at least seven different receptor proteins of which five can also be precipitated with an anti-(C1/C2) monoclonal antibody. Thus at least three different TCR–δ heterodimers are expressed by CH12-responding T cells. The Thy-1, CD4, CD8, Ly-5(B220) cells can provide help to CH12 cells for Ig secretion even in the absence of the nominal antigen for the B lymphoma cells, in summary, these results demonstrate that in normal mice there is a small population of CD4, CD8, Ly-5(B220) T cells with γ/δ receptors which can provide help for a syngeneic B cell lymphoma. [ABSTRACT FROM PUBLISHER]

Published
1989

46. Babesia microtiPrimarily Invades Mature Erythrocytes in Mice

Author

Borggraefe, Ingo, Yuan, Jie, Telford, Sam R., Menon, Sanjay, Hunter, Rouette, Shah, Sohela, Spielman, Andrew, Gelfand, Jeffrey A., Wortis, Henry H., and Vannier, Edouard

Abstract

ABSTRACTBabesia microtiis a tick-borne red blood cell parasite that causes babesiosis in people. Its most common vertebrate reservoir is the white-footed mouse. To determine whether B. microtiinvades reticulocytes, as does the canine pathogen B. gibsoni, we infected the susceptible inbred mouse strains C.B-17.scid and DBA/2 with a clinical isolate of B. microti. Staining of fixed permeabilized red blood cells with 4′,6′-diamidino-2-phenylindole or YOYO-1, a sensitive nucleic acid stain, revealed parasite nuclei as large bright dots. Flow cytometric analysis indicated that parasite DNA is primarily found in mature erythrocytes that expressed Babesiaantigens but not the transferrin receptor CD71. In contrast, CD71-positive reticulocytes rarely contained Babesianuclei and failed to express Babesiaantigens. Accordingly, the frequency of YOYO-1-positive, CD71-negative cells strongly correlated with parasitemia, defined as the frequency of infected red blood cells assessed on Giemsa-stained blood smears. Importantly, the absolute numbers generated by the two techniques were similar. Parasitemia was modest and transient in DBA/2 mice but intense and sustained in C.B-17.scid mice. In both strains, parasitemia preceded reticulocytosis, but reticulocytes remained refractory to B. microti. In immunocompetent C.B-17 mice, reticulocytosis developed early, despite a marginal and short-lived parasitemia. Likewise, an early reticulocytosis developed in resistant BALB/cBy and B10.D2 mice. These studies establish that B. microtihas a tropism for mature erythrocytes. Although reticulocytes are rarely infected, the delayed reticulocytosis in susceptible strains may result from parasite or host activities to limit renewal of the mature erythrocyte pool, thereby preventing an overwhelming parasitemia.

Published
2006
Full Text
View/download PDF

47. Electrophoretic separation of cells in a density gradient

Author

Griffith, Ann L., Catsimpoolas, Nicholas, and Wortis, Henry H.

Abstract

A bulk electrophoretic method is described for the separation of mammalian cells in Ficoll-sucrose density gradients. The fractionation of cells is performed in a simple commercially available apparatus (Buchler Poly-Prep) which should facilitate the application of the technique in various laboratories. Details of the experimental procedure are presented along with typical model separations of erythrocytes from various species and mouse lymphocytes.

Published
1975
Full Text
View/download PDF

48. The Ability of CD40L, but Not Lipopolysaccharide, To Initiate Immunoglobulin Switching to Immunoglobulin G1 Is Explained by Differential Induction of NF-?B/Rel Proteins

Author

Lin, Shih-Chang, Wortis, Henry H., and Stavnezer, Janet

Abstract

ABSTRACTAntibodies of the immunoglobulin G1 class are induced in mice by T-cell-dependent antigens but not by lipopolysaccharide (LPS). CD40 engagement contributes to this preferential isotype production by activating NF-?B/Rel to induce germ line ?1 transcripts, which are essential for class switch recombination. Although LPS also activates NF-?B, it poorly induces germ line ?1 transcripts. Western blot analyses show that CD40 ligand (CD40L) induces all NF-?B/Rel proteins, whereas LPS activates predominantly p50 and c-Rel. Electrophoretic mobility shift assays show that in CD40L-treated cells, p50-RelA and p50-RelB dimers are the major NF-?B complexes binding to the germ line ?1 promoter, whereas in LPS-treated cells, p50–c-Rel and p50-p50 dimers are the major binding complexes. Transfection of expression plasmids for NF-?B/Rel fusion proteins (forced dimers) indicates that p50-RelA and p50-RelB dimers activate the germ line ?1 promoter and that p50–c-Rel and p50-p50 dimers inhibit this activation by competitively binding to the promoter without activating the promoter. Therefore, germ line ?1 transcription depends on the composition of NF-?B/Rel proteins.

Published
1998
Full Text
View/download PDF

50. ABNORMAL DEVELOPMENT OF THE THYMUS IN "NUDE" MICE

Author

Wortis, Henry H., Nehlsen, Sandra, and Owen, John J.

Abstract

Nude mice bearing grafts of normal thymus reject skin grafts and have low, but higher than usual, lymphocyte counts. Nude bone marrow can successfully repopulate the thymus and thymus-derived areas of lethelly irradiated recipient mice. Attempts to reconstitute nude mice with normal fetal liver failed. The so-called thymic rudiment of nude mice when grafted to normal mice did not develop thymocytes. These experiments show that nude mice suffer from a defect of the epithelial portion of the thymus rather than of the precursors of thymocytes.

Published
1971
Full Text
View/download PDF

Catalog

Books, media, physical & digital resources
See catalog results