bluuebunny/crossref_metadata_2025_split huggingface dataset:
Control of lymphocyte recirculation in man. I. Differential regulation of the peripheral lymph node homing receptor L-selectin on T cells during the virgin to memory cell transition.
Authors: Picker L J , Treer J R , Ferguson-Darnell B , Collins P A , Buck D , Terstappen L W 
Published: December 2022

Abstract
Conventional virgin lymphocytes of a given class show relatively homogeneous recirculation through secondary lymphoid tissues, whereas memory/effector populations are composed of distinct subsets with differential, often tissue-selective migratory capability. In keeping with these observations, CD45RAhigh/ROlow "virgin" T cells in human peripheral blood uniformly express the peripheral lymph node homing receptor (HR) L-selectin, whereas among the CD45RAlow/ROhigh "memory/effector" subset, the expression of this HR is bimodal. To investigate the mechanisms responsible for the generation of memory/effector T cell subsets with differential homing potential, we developed a multiparameter flow cytometric technique that defines a common pathway of post-thymic T cell differentiation in secondary lymphoid tissues. Our analyses indicate that the virgin to memory T cell transition is characterized by a stepwise, unidirectional progression through distinct CD45RA+/RO+ intermediates that allow the in vivo discrimination of early, middle, and late transitional T cells. In normal peripheral blood, few T cells with a transitional phenotype are identified, but in secondary lymphoid tissues, 2 to 10% of T cells have this phenotype, including those CD45RA+ T cells that 1) are morphologically blasts, 2) are in S or G2/M phase of the cell cycle, or 3) express activation Ag. General adhesion molecules (LFA-1, LFA-3, ICAM-1) are uniformly up-regulated concordant with changes in T cell expression of CD45RA/RO in all tissues examined. Early in the transition, L-selectin is also uniformly up-regulated, but in subsequent stages, T cell expression of this HR is preferentially down-regulated in mucosal lymphoid tissues, and retained in peripheral lymph node. Differential regulation of L-selectin can also be demonstrated in vitro by the activation of virgin T cells in the presence of specific cytokines--IL-2 induces L-selectin down-regulation, whereas IL-6 and particularly TGF-beta 1 promote L-selectin up-regulation. Taken together, these findings support the hypothesis that local microenvironments within particular secondary lymphoid tissues influence HR expression at the time of CD45RA/RO conversion, and thereby contribute to the formation of CD45RAlow/ROhigh memory/effector T cell populations with tissue-selective homing behavior.
A monoclonal antibody to recombinant human IFN-alpha receptor inhibits biologic activity of several species of human IFN-alpha, IFN-beta, and IFN-omega. Detection of heterogeneity of the cellular type I IFN receptor.
Authors: Benoit P , Maguire D , Plavec I , Kocher H , Tovey M , Meyer F 
Published: December 2022

Abstract
A cDNA encoding a 63-kDa human IFN-alpha R (hIFN-alpha R) has recently been cloned. Mouse cells transfected with this cDNA failed to show any signal transmission for IFN-beta, suggesting the involvement of additional chains in the receptor complex. We have expressed in Escherichia coli and COS 7 cells a soluble recombinant protein (sIFN-alpha R) comprising the extracellular domain of the hIFN-alpha R fused at the carboxyl terminus to a sequence of five histidine residues. The sIFN-alpha R was affinity purified and used to generate mAb. One mAb, 64G12, which recognized the cellular receptor as well as the recombinant proteins was found to neutralize the biologic activity of IFN-alpha, -beta, and -omega and natural type I IFN, but not IFN-gamma. To our knowledge, this is the first report of a neutralizing mAb against the human IFN-alpha R. Interestingly, we found that the affinity of this antibody for the cellular receptor depended on the cell line used. These results provide strong evidence that the cloned hIFN-alpha R chain is required for binding and signal transmission of all subspecies of type I IFN and suggest a structural heterogeneity of the receptor at the cell surface.
Role of peripheral hemopoietic chimerism in achieving donor-specific tolerance in adult mice.
Authors: Maeda T , Eto M , Nishimura Y , Nomoto K , Kong Y Y , Nomoto K 
Published: December 2022

Abstract
The role of peripheral hemopoietic chimerism in the induction and maintenance of donor-specific tolerance was investigated by our tolerance-inducing method using cyclophosphamide (CP). As has been previously reported, CP injection at a dose of 200 mg/kg to C3H (Thy-1.2, Mls-1b) mice 2 days after priming with 10(8) viable AKR (Thy-1.1, Mls-1a) spleen cells (SC) resulted in both establishment of mixed chimerism and selective elimination of V beta 6+CD4+ T cells in the periphery. When, instead of viable SC, 1300 rad irradiated 10(8) AKR SC were used for priming to C3H mice, CP treatment 2 days after the priming also caused significant but, as compared with priming with nonirradiated viable cells, incomplete elimination of V beta 6+ T cells in the periphery. In these mice, no hemopoietic chimerism was found. In parallel with this incomplete elimination of peripheral V beta 6+ T cells, LN cells of these mice showed reduced but considerable response to AKR SC. However, once hemopoietic chimerism was introduced to these incompletely tolerant mice by an injection with donor-type viable [AKR x C3H]F1 SC 2 days after CP-treatment, LN cells from these newly established chimeras, irrespective of presence or absence of the thymus, became completely nonresponsive to AKR while preserving normal response to BALB/c (third party). This state of nonresponsiveness was accompanied by clonal elimination of the remaining V beta 6+ T cells in the periphery. These results indicate that peripheral chimerism promoted profound tolerance to donor-Mls Ag specifically. Furthermore, from experiments of skin grafting, we demonstrated that tolerance to minor histocompatibility Ag was also achieved in the presence of peripheral hemopoietic chimerism.
Characterization of responses of normal human T cells to Trypanosoma cruzi antigens.
Authors: Piuvezam M R , Russo D M , Burns J M , Skeiky Y A , Grabstein K H , Reed S G 
Published: December 2022

Abstract
The stimulation of normal human PBMC by Trypanosoma cruzi Ag was analyzed. PBMC showed significant in vitro proliferation in response to parasite lysate (Tct), with stimulation indices ranging from 10 to 400, peaking at 6 to 7 days. The cells stimulated with Tct produced significant levels of IL-2. To determine which cells proliferated in response to Tct, PBMC were separated into T- and B-enriched cell populations. Purified T cells, but not B cells, proliferated strongly to Tct. The T cell response required APC and was processing dependent. T cell lines generated against Tct proliferated in response to parasite lysate only in the presence of autologous APC and produced IL-2, IL-6, and IFN-gamma but not IL-4 in response to PMA plus ionomycin. Although there were a significant number of CD45Ra+ cells, the majority of the cells in these T cell lines were CD45Ro+. The V beta usage of Tct-responding T cells was heterogeneous, with most V beta genes represented among the responding cells. An immunodominant repeat Ag (TcD) and a ribosomal phosphoprotein (P0) of T. cruzi elicited strong proliferative responses in all subjects tested. These data indicate the presence of T cell-stimulatory Ag in Tct, characterized by nonpreferential usage of the V beta gene families. The strong stimulation of normal human PBMC by Tct may contribute to immunologic alterations seen in T. cruzi infection.
Mapping human T cell epitopes in leishmania gp63. Identification of cross-reactive and species-specific epitopes.
Authors: Russo D M , Jardim A , Carvalho E M , Sleath P R , Armitage R J , Olafson R W , Reed S G 
Published: December 2022

Abstract
Both a conserved surface metalloprotease of leishmania, gp63 as well as certain gp63-derived peptides, have been shown to have immunoprophylactic potential in mouse models of leishmaniasis. In addition, PBMC from individuals with cutaneous, mucosal, or cured visceral leishmaniasis respond in vitro to both native and rgp63. In this report, we mapped human T cell epitopes within gp63. T cells from leishmaniasis patients responded in vitro to certain peptides of gp63 by proliferation and IFN-gamma production. One peptide, (PT7), stimulated cells from all individuals tested (n = 7). Anti-PT7 T cell lines derived from PBMC of a mucosal leishmaniasis patient contained a heterogeneous population of cells which responded by proliferation and IFN-gamma production to in vitro stimulation with Leishmania promastigote lysate. Another peptide (PT1) derived from Leishmania chagasi gp63 stimulated PBMC from an L. chagasi patient although the corresponding Leishmania major-derived peptide did not. Both L. major PT7 and L. chagasi PT1 were able to induce anti-Leishmania-specific T cell lines from normal human PBMC. These T cell lines responded to in vitro stimulation with promastigote lysate indicating that both peptides were immunogenic for naive T cells in vitro. In conclusion, both antigenic and immunogenic gp63 peptide sequences have been defined, some appearing to be conserved among Leishmania species and at least one that appears to be species specific.
Cross-linking of CD14 molecules on monocytes results in a CD11/CD18- and ICAM-1-dependent adherence to cytokine-stimulated human endothelial cells.
Authors: Beekhuizen H , Blokland I , van Furth R 
Published: December 2022

Abstract
The myeloid differentiation protein CD14 that is expressed on the surface of mature monocytes contributes to the adherence of monocytes to cytokine-stimulated monolayers of human macrovascular endothelial cells (EC). It has also been observed that the initial adherence of monocytes to cultured cytokine-stimulated EC eventually results in an ICAM-1- and LFA-1 (CD11a/CD18)-dependent adherence, which coincides with stretching and lateral migration of the monocytes over the surface of EC. Recently, it was reported that CD14 mediates monocyte activation and can induce a change in the avidity of CD11a/CD18 for its ligand ICAM-1. The aim of the present study was to investigate whether activation of monocytes by CD14 elicits a CD11/CD18-dependent adhesion of monocytes to ICAM-1 on rIL-1 alpha-stimulated EC. Incubation of monocytes with murine anti-CD14 mAb alone did not mobilize intracellular calcium but the subsequent addition of F(ab')2 anti-mouse Ig, which caused cross-linking of CD14 on the surface of monocytes, induced a transient rise in cytosolic free calcium concentration and enhanced the percentage monocytes that adhered to monolayers of macrovascular venous EC stimulated with rIL-1 alpha for 24 h, but not to nonstimulated EC. The elevated adhesion was decreased with monocytes were preincubated with staurosporine, an inhibitor of intracellular protein kinase activity and was markedly inhibited by mAb against the common beta 2-subunit (CD18) of the CD11/CD18 molecules on monocytes and by mAb against ICAM-1 on 24-h rIL-1 alpha-stimulated venous EC. These studies provide evidence for the hypothesis that the binding of monocytes via CD14 to rIL-1 alpha-stimulated EC generates an intracellular response in monocytes and triggers an adhesion mechanism that allows CD11/CD18 molecules on monocytes to bind to ICAM-1 on EC.
Modulation of IL-1-induced neutrophil migration by dexamethasone and lipocortin 1.
Authors: Perretti M , Flower R J 
Published: December 2022

Abstract
IL-1 is a pro-inflammatory cytokine which controls many features of the immune and inflammatory response. When injected into a mouse 6-day-old air-pouch, human rIL-1 (1 to 100 ng) induced in a dose-dependent fashion a migration of PMN that could be reliably assessed 4 h after injection. Both IL-1 alpha and IL-1 beta were active in this model. The effect of the cytokine was inhibited by local administration of actinomycin D (1 to 10 micrograms), alpha-melanocyte-stimulating hormone (200 micrograms), and a mAb recognizing IL-1R type I (10 micrograms). Indomethacin (1 mg/kg), an inhibitor of cyclo-oxygenase, and BW4AC (2 mg/kg), a selective lipoxygenase inhibitor, were without effect but moderate inhibition was seen with the platelet-activating factor antagonist WEB2086 (1 to 10 mg/kg). The glucocorticoid dexamethasone (0.015 to 1.5 mg/kg) potently inhibited the elicitation of neutrophils induced by IL-1 when given systemically 2 h before the cytokine. The steroid-induced anti-inflammatory protein lipocortin 1 (LC1) also produced a dose-dependent inhibition of PMN migration into the pouch with an ED50 of approximately 0.15 to 0.21 mg/kg. The denatured protein was without effect. Passive immunization of mice with a polyclonal sheep antiserum or a mAb raised against LC1 abolished the inhibitory action of dexamethasone whereas preimmune serum or control IgG were without significant effect. These findings provide further evidence that LC1 is involved in the anti-inflammatory action of glucocorticosteroids and suggest that this protein may act as an endogenous regulator of IL-1 action.
Inhibition of phorbol ester-induced T cell proliferation by bryostatin is associated with rapid degradation of protein kinase C.
Authors: Isakov N , Galron D , Mustelin T , Pettit G R , Altman A 
Published: December 2022

Abstract
The bryostatins (Bryo) represent a group of immunomodulators that counteract the tumor-promoting effects of PMA. In contrast to the mitogenic effect of PMA on human peripheral blood T lymphocytes, Bryo was nonmitogenic and, furthermore, it inhibited PMA-induced T cell proliferation in a dose-dependent manner when added up to 2 days after PMA. Because both Bryo and PMA bind to, and activate, protein kinase C (PKC), we compared their effects on PKC expression and activity in human PBL or leukemic T cells (Jurkat). After treatment for 5 to 60 min, both Bryo and PMA were found to: a) activate PKC in vitro with similar dose-response curves; b) induce a nearly complete cytosol-to-membrane translocation of enzymatically active, Ca(2+)-dependent PKC and of distinct immunoreactive PKC isoforms in intact PBL; and c) stimulate similar patterns of protein phosphorylation. After a longer, 20-h treatment with PMA (20 nM), a considerable portion of PKC was still membrane-associated, and the total amount of immunoreactive PKC was not reduced considerably. In contrast, Bryo induced a marked loss of cellular immunoreactive PKC, including PKC-alpha and -beta. These results were paralleled by measurements of total cytosol- or membrane-associated PKC enzymatic activity. Thus, substantial PKC activity was associated with the particulate fraction of PMA-, but not Bryo-stimulated PBL. Furthermore, inhibition of PMA-induced T cell proliferation by Bryo also correlated with a reduction in the amount of cytosolic and membrane-bound immunoreactive PKC and enzymatic activity, demonstrating the dominance of Bryo over PMA. We propose that Bryo inhibits PMA-induced T cell proliferation by causing rapid degradation of PKC, reflecting a requirement of persistent PKC stimulation (lasting approximately 48 h) for the activation of human T cells and progression through the cell cycle.
Expression and function of B7 on human epidermal Langerhans cells.
Authors: Symington F W , Brady W , Linsley P S 
Published: December 2022

Abstract
The B7 molecule is expressed by APC that can costimulate T cells by binding the T cell surface receptors CD28 and CTLA-4. The human epidermal Langerhans cell (LC) is one of the most potent APC, yet B7 expression by this cell type has not previously been assessed. We used a CTLA4-Ig fusion protein that binds B7 with high avidity to probe cell surface expression of B7 by cultured and noncultured LC. LC cultured for 1 or more days were specifically stained with biotinylated CTLA4-Ig and fluorescent streptavidin. In contrast, binding of CTLA4-Ig to freshly isolated LC was not detected. The cell surface distributions of B7 and of HLA-DR on cultured LC differed, as CTLA4-Ig binding was localized to discrete foci, whereas anti-DR mAb uniformly stained the LC plasma membrane. Analyses of epidermal cell (EC) mRNA indicated that the B7 gene is expressed by these cells. Thus, B7 gene probes specifically hybridized to polymerase chain reaction-amplified B7 mRNA isolated from cultured and noncultured EC. As LC are the only normal epidermal cell type that induces proliferation of allogeneic T cells, the role of B7 in this LC function was studied by coculturing highly purified resting CD4+ T cells and allogeneic EC in the presence of CTLA4-Ig, anti-CD54 (RR/1, anti-intercellular adhesion molecule-1) mAb, or both. CTLA4-Ig and RR/1 each inhibited CD4+ T cell responses to freshly isolated allogeneic EC, and cooperative inhibition of more than 90% was observed in cultures treated with both CTLA4-Ig and RR/1 at 5 micrograms/ml. CTLA4-Ig inhibited stimulation by either fresh EC or cultured EC, suggesting that the increased potency of cultured LC vs noncultured LC may reflect the time needed for noncultured LC to express cell surface B7 in vitro. These studies indicate that B7 is expressed on the cell surface of cultured LC, and that LC B7 costimulates the proliferation of resting allogeneic CD4+ T cells.
Increased function of P-glycoprotein in T lymphocyte subsets of aging mice.
Authors: Witkowski J M , Miller R A 
Published: December 2022

Abstract
The age-associated decline in T lymphocyte function can be attributed in part to shifts between subsets (in particular the accumulation of memory T cells at the expense of naive T cells), and in part to alterations of function within the different T lymphocyte subsets. We show that the fluorochrome rhodamine-123 (R123) can distinguish further subdivisions within the naive and memory populations of both CD4 and CD8 T cells in the mouse. Aging leads to a progressive increase in the proportion of T cells in each subset that stain dimly with R123, and a corresponding decrease in the proportion of R123hi T cells, which are typical in young mice. We show that differential R123 staining between T cell subsets is due to variation in the activity of P-glycoprotein (P-Gp), the 170 kDa, ATP-dependent plasma membrane pump that mediates multiple-drug resistance. All T cells initially take up equivalent amounts of R123, but some T cells then can extrude the dye in a temperature-dependent process that is blocked by each of four pharmacologically disparate inhibitors of P-Gp function. Immunofluorescence experiments suggest that T cells from old and young mice have equal amounts of the P-Gp molecule itself, suggesting that differences in R123 extrusion may depend on posttranslational regulation of P-Gp activity.
Nonrandom T cell receptor usage in the allorecognition of HLA-DR1 microvariation.
Authors: Hurley C K , Steiner N , Wagner A , Geiger M J , Eckels D D , Rosen-Bronson S 
Published: December 2022

Abstract
Microvariation within the DR1 Ag family has created two DR molecules which differ only at beta-chain residues 85 (Val/Ala) and 86 (Gly/Val). TCR utilized by human alloproliferative T lymphocyte clones which can distinguish between these microvariants have been characterized by cDNA sequencing. The alpha- and beta-chain cDNA utilize a diverse set of variable (V) gene segments although the same V segment may be used by different individuals suggesting that V segment usage by the alloreactive T lymphocyte clones is nonrandom. There appears to be no difference in the repertoire of V segments utilized by T lymphocytes that preferentially recognize specific DR1 allelic products (DR(alpha,beta 1*0101) or DR(alpha,beta 1*0102)) and T lymphocytes that recognize both DR1 molecules. In contrast, the junctional regions of both alpha- and beta-chains are diverse in length and sequence although some common elements can be observed among TCR which share V gene segments. Two TCR which share V alpha and V beta gene segments differ in fine specificity for specific DR1 allelic products implicating the junctional regions of alpha- and beta-chains in the recognition of differentially bound peptides and/or in recognition of DR beta-chain residues 85 and 86. The stimulation of many diverse TCR by the limited allelic variation between DR(alpha,beta 1*0101) and DR(alpha,beta 1*0102) molecules suggests that the effect of DR microvariation on human immune responsiveness may be substantial.
Clonal analysis of a human antibody response. II. Sequences of the VH genes of human IgM, IgG, and IgA to rabies virus reveal preferential utilization of VHIII segments and somatic hypermutation.
Authors: Ikematsu H , Harindranath N , Ueki Y , Notkins A L , Casali P 
Published: December 2022

Abstract
The construction of mAb-producing cell lines has been instrumental in dissecting the fine specificities and genetic makeup of murine antibodies to exogenous and self Ag. The analysis of the genetic composition of human antibody responses has been hampered by the difficulty in generating human mAb of predetermined class and specificity. Using B lymphocytes from three healthy subjects vaccinated with inactivated rabies virus vaccine, we generated nine human mAb binding to rabies virus and analyzed the genes encoding their VH regions. Six mAb (five IgG1 and one IgA1) were monoreactive and displayed high affinities for rabies virus Ag. The remaining three mAb (IgM) were polyreactive and displayed lower affinities for rabies virus Ag. Seven mAb (3 IgG1, the IgA1, and the three IgM) utilized VH gene segments of the VHIII family. The remaining two IgG1 mAb utilized gene segments of the VHI and VHIV families. Of the seven expressed VHIII family genes, three were similar to the germline VH26c gene, two to the germline 22-2B gene, one to the germline H11 gene, and one to the germline 8-1B gene. The expressed VHI and VHIV genes displayed sequences similar to those of the germline hv1263 and V71-4 genes, respectively. The VH genes of all but one mAb (mAb55) resembled those that are predominantly expressed by C mu + clones in human fetal liver libraries. When compared with known germline sequences, the VH genes of the rabies virus-binding mAb displayed variable numbers of nucleotide differences. That such differences resulted from a process of somatic hypermutation was formally demonstrated (by analyzing DNA from polymorphonuclear neutrophil of the same subject whose B lymphocytes were used for the mAb generation) in the case of the VH gene of the high affinity (anti-rabies virus glycoprotein) IgG1 mAb57 that has been shown to efficiently neutralize the virus in vitro and in vivo. The distribution, mainly within the complementarity determining regions, and the high replacement-to-silent ratio of the mutations, were consistent with the hypothesis that the mAb57-producing cell clone underwent a process of Ag-driven affinity maturation through clonal selection. The D gene segments of the rabies virus-selected mAb were heterogeneous and, in most cases, flanked by significant N segment additions. The JH segment utilization was unbalanced and reminiscent of those of the adult and fetus. Four mAb utilized JH4, two JH6, two JH3, and one JH5; no mAb utilized JH1 or JH2 genes.(ABSTRACT TRUNCATED AT 400 WORDS)