bluuebunny/crossref_metadata_2025_split huggingface dataset:
Characterization of distinct stages during the differentiation of human CD69+CD3+ thymocytes and identification of thymic emigrants.
Authors: Vanhecke D , Leclercq G , Plum J , Vandekerckhove B 
Published: December 2022

Abstract
During thymocyte development, CD69 expression is induced at an early stage of positive selection. To examine the differentiation of human CD69+CD3+ thymocytes, discrete phenotypes were defined by the relative expression of CD69, CD27, CD1, and CD45RA/RO: CD3+CD69- thymocytes were CD27-CD1+CD45RA-/RO+ (phenotype I), whereas the CD3+ CD69+ population could be subdivided into CD27-CD1+CD45RA-/RA+ (phenotype II), CD27+CD1+CD45RA-/RO+ (phenotype III), CD27+CD1-CD45RA-/dull/RO+ (phenotype IV), and CD27+CD1-CD45RA+/ROdull (phenotype V) thymocytes. Phenotype I thymocytes were CD4+CD8 alpha beta + double positive (DP). Phenotype II thymocytes contained DP and CD4+CD8 alpha dullCD8 beta- cells, whereas phenotype III thymocytes were DP and mostly CD4dullCD8 alpha beta+, indicating that CD27 on DP cells may be a marker for CD8-committed cells. Results obtained with SCID-hu mice, transplanted with human fetal thymus and liver, showed that immature human CD69-CD3+ thymocytes were corticosteroid-sensitive, whereas essentially all CD69+CD3+ cells were resistant. During differentiation of one cohort of corticosteroid-resistant CD69+CD3+ thymocytes, phenotype II and III thymocytes, disappeared within a week, whereas the percentage of phenotype IV and especially V thymocytes increased, suggesting that the latter represent the end stages in differentiation. Recent thymic emigrants in SCID-hu mice were identified as CD69-CD27+CD1-CD45RA-/dull/RO+ or CD45RA+/ROdull cells. Because phenotype IV and phenotype V thymocytes rapidly lose CD69 expression in cell culture, these thymocytes are probably the cells that are exported from the thymus. In conclusion, after the acquisition of CD69, thymocyte differentiation appears to continue in an ordered pattern, and cells that eventually leave the thymus are CD69-CD1-CD45RA+ or CD45RA-/dull.
Variable influence of MHC polymorphism on the recognition of bacterial superantigens by T cells.
Authors: Wen R , Blackman M A , Woodland D L 
Published: December 2022

Abstract
Superantigen recognition by some T cells is strongly influenced by polymorphic residues of the MHC class II molecule, suggesting that the TCR contacts the class II molecule during superantigen engagement. However, the degree of MHC preference varies with V beta expression. For example, the recognition of staphylococcal enterotoxin B (SEB) by murine V beta 14+ T cell hybridomas is strongly influenced by MHC polymorphism, whereas the recognition of SEB by V beta 8.2+ hybridomas appears to be independent of MHC polymorphism. One possible explanation for this difference is that V beta 14+ TCR may have a lower avidity for SEB such that the stability of the TCR/SEB/MHC complex is more strongly influenced by potential TCR/MHC interactions. To investigate this possibility, we examined the MHC preference of SEB recognition by murine V beta 8.2+/CD4+ T cell hybridomas in which we altered the strength of SEB recognition. First, we compared the recognition of wild-type SEB and mutant SEB, which only weakly activates T cells. Second, we compared recognition of SEB presented by I-E and I-A molecules, which differ in their affinity for SEB. In both cases, the degree of MHC preference was significantly increased when the strength of SEB recognition was reduced. Furthermore, we used mutant MHC class II molecules to show that the degree of MHC preference was controlled by residues of the class II molecule predicted to interact with the TCR during SEB recognition. Taken together, these data support the idea that there is a TCR/MHC interaction during SEB recognition, and the influence of this interaction varies with the overall avidity of the TCR/SEB/MHC complex.
Structural requirements of peptide and MHC for DR(alpha, beta 1*0401)-restricted T cell antigen recognition.
Authors: McNicholl J M , Whitworth W C , Oftung F , Fu X , Shinnick T , Jensen P E , Simon M , Wohlhueter R M , Karr R W 
Published: December 2022

Abstract
We identified functionally important regions of the DR(alpha, beta 1*0401) peptide binding site and present a model of bound peptide. DR(alpha, beta 1*0401)-restricted T cell recognition and peptide binding of Mycobacterium leprae (ML) peptide 38-50 and overlapping peptides from the 18-kDa heat-shock protein were analyzed. ML38-50 is unusual in its restricted binding pattern, binding to only one of five DR4 subtypes and no other DR molecules tested. Amino acid substitutions were introduced into ML38-50 and the DR(alpha, beta 1*0401) peptide binding site at positions likely to influence peptide-MHC or peptide- or MHC-TCR interactions. Peptide binding, T cell proliferation, and computer modeling studies suggest that residues 39F, 42E, and 44D of ML38-50 interact with pockets 1, 4, and 6, respectively, of the peptide binding site. Only DR(alpha, beta 1*0401) substitutions at residues in pockets 4 or 7 prevented binding of ML38-50, while multiple substitutions at other positions negatively affected its T cell recognition. In contrast, T cell recognition of some high affinity ML peptides that overlapped ML38-50, and contained N-terminal extensions, was only abolished with pocket 4 substitutions. An inverse correlation of peptide affinity for DR(alpha, beta 1*0401) with negative effects of MHC substitutions on T cell recognition of the overlapping ML peptides was observed. Thus, some regions, such as pocket 4, dominantly influence T cell recognition of multiple DR(alpha, beta 1*0401)-binding peptides. However, each DR(alpha, beta 1*0401)-binding peptide appears to have unique properties that determine the outcome of its MHC-peptide interactions and the relative importance of other polymorphic pockets.
Complexity of the cytokine and antibody response elicited by immunizing mice with Plasmodium yoelii circumsporozoite protein plasmid DNA.
Authors: Mor G , Klinman D M , Shapiro S , Hagiwara E , Sedegah M , Norman J A , Hoffman S L , Steinberg A D 
Published: December 2022

Abstract
The number, type, and location of cytokine- and Ab-secreting cells activated in mice immunized and boosted with plasmid DNA encoding the circumsporozoite protein of the malarial parasite Plasmodium yoelii (PyCSP) were monitored. The initial humoral response was localized to the draining lymph nodes and was characterized by production of IgG1 anti-PyCSP Abs and the Th2 cytokine IL-4. In contrast, the secondary response was dominated by IFN-gamma production (a Th1 cytokine) and the secretion of IgG2a anti-PyCSP Abs in the spleen. PyCSP DNA and mRNA were detected only in the quadriceps muscles (sites of plasmid injection), yet these sites lacked either cytokine- or Ab-secreting cells. These findings indicate that circulating lymphocytes encounter plasmid-encoded Ag in the muscle bed, initiate a humoral response in the draining lymph nodes, and then seed distal lymphoid organs. Profound differences were observed between the primary and secondary immune responses induced by plasmid immunization, which may influence vaccine efficacy.
Dissection of strain difference in acquired protective immunity against Mycobacterium bovis Calmette-Guérin bacillus (BCG). Macrophages regulate the susceptibility through cytokine network and the induction of nitric oxide synthase.
Authors: Yoshida A , Koide Y , Uchijima M , Yoshida T O 
Published: December 2022

Abstract
Protection against infection with intracellular pathogens operates in two stages, early innate resistance and late acquired protective immunity (API), in inbred mouse strains. Although both C57BL/10 (B10) and BALB/c mice bear the susceptible phenotype of innate resistance, Calmette-Guérin bacillus (BCG) vaccination generated efficient API in B10 but not in BALB/c mice. Employing a specific nitric oxide (NO) synthase inhibitor, we revealed that NO production plays a pivotal role in the API of B10 mice. Consistent with this, expressions of the inducible isoform of NO synthase (iNOS) protein and mRNA were significantly higher in the spleen of B10 mice than in that of BALB/c mice. Furthermore, IFN-gamma, a potent inducer of iNOS, and mRNAs for IL-12 (p40); an inducer of IFN-gamma and IL-2 were also vigorously expressed in the spleen of B10 mice compared with that of BALB/c mice. In an attempt to clarify the mechanism by which the different capacities for API are generated, we analyzed the cytokine network between T cells and macrophages in both B10 and BALB/c mice. We found that multiple functions of macrophages, which include capacities to express IL-12 (p40) mRNA in response to BCG and to express mRNAs for iNOS and IL-12 (p40) in response to IFN-gamma, were impaired in BALB/c mice as compared with B10 mice. However, T cells appeared to express comparable level of IFN-gamma mRNA in both strains when stimulated with IL-12. Taken together, these results indicate that the macrophage functions play a pivotal role in both the induction and effector phases of API to determine the susceptibility of mice to BCG infection.
Divergence in macrophage insulin-like growth factor-I (IGF-I) synthesis induced by TNF-alpha and prostaglandin E2.
Authors: Fournier T , Riches D W , Winston B W , Rose D M , Young S K , Noble P W , Lake F R , Henson P M 
Published: December 2022

Abstract
Increased synthesis of insulin-like growth factor I (IGF-I), a fibroblast growth factor, is induced in murine macrophages by TNF-alpha. TNF-alpha also induces macrophages to express cytocidal activity, but only during costimulation with IFNs. Since prostaglandin E2 (PGE2) is known to inhibit macrophage cytocidal activity, its possible reciprocal enhancement of IGF-I synthesis was examined. PGE2 or dibutyryl cyclic AMP (dbcAMP) stimulated the synthesis of IGF-I similarly to TNF-alpha in magnitude and time course. TNF-alpha did not increase IGF-I synthesis by first inducing PGE2 synthesis, because indomethacin was unable to block the effect of TNF-alpha. PGE2 did not stimulate IGF-I synthesis by first inducing TNF-alpha production, because 1) anti-TNF-alpha Ab did not block PGE2-induced IGF-I synthesis, and 2) PGE2 down-regulated TNF-alpha mRNA levels and did not affect levels of the cytokine in supernatants. Moreover, the difference in the induction of IGF-I was observed at the level of signal transduction, in that PGE2 and dbcAMP increased cAMP-dependent protein kinase (PKA) activity, whereas TNF-alpha stimulated the mitogen-activated protein (MAP) kinase pathway. Divergence between the two pathways was also noted in the regulation of IGF-I at the mRNA level, and an additive effect on IGF-I synthesis was observed when cells were incubated with the combination of TNF-alpha plus PGE2 or dbcAMP. Collectively, these data suggest that TNF-alpha and PGE2 stimulate IGF-I synthesis in macrophages by two separate pathways, and that PGE2 acts as a positive stimulus for IGF-I synthesis through a cyclic AMP/PKA pathway.
An essential role of prostaglandin E on mouse mast cell induction.
Authors: Hu Z Q , Asano K , Seki H , Shimamura T 
Published: December 2022

Abstract
We previously established a system for induction of mucosal-type mast cells from mouse spleen cells by long term culture without exogenous IL-3. FCS was important and was able to be divided into mast cell-inducible and non-mast cell-inducible sera. LPS contaminated in FCS was responsible for the mast cell induction. However, we unexpectedly found that both supernatants recovered from the cultures with mast cell-inducible and non-mast cell-inducible sera contained endogenous IL-3. Furthermore, addition of rIL-3 to the cultures with non-mast cell-inducible sera had no effect or induced only a small number of mast cells. This indicates that IL-3 alone is not enough for mast cell induction and that some inflammatory factor(s) induced by LPS is also essential. Prostaglandin E1 (PGE1) and PGE2 induced mast cells in a dose-dependent manner when added into the cultures. The activity of LPS for mast cell induction was inhibited by indomethacin. However, indomethacin failed to inhibit the mast cell induction by exogenous PGE. Exogenous PGE antagonized the indomethacin-induced inhibition of mast cell induction by LPS. Cholera toxin and dibutyryl cyclic AMP (cAMP) also induced mast cells. The A and B subunits of cholera toxin, PGF2 alpha, PGD2, and dibutyryl cGMP failed to induce mast cells. Furthermore, mast cell induction by PGE was dose-dependently suppressed by inhibitors for cAMP-dependent A kinase. The above results show that for mast cell induction, IL-3 needs the cooperation of PGE or other stimulants that can elevate the production of the second messenger cAMP in mast cell precursors.
IL-3, IL-5, and granulocyte-macrophage colony-stimulating factor potentiate basophil mediator release stimulated by eosinophil granule major basic protein.
Authors: Sarmiento E U , Espiritu B R , Gleich G J , Thomas L L 
Published: December 2022

Abstract
We have examined the potential of IL-3, IL-5, and granulocyte-macrophage (GM)-CSF to enhance basophil activation by eosinophil granule major basic protein (MBP). Preincubating basophil-containing mononuclear cells with 0.01 to 10 ng/ml IL-3 or IL-5 for 15 min at 37 degrees C caused a concentration-dependent enhancement of histamine release stimulated by 1.5 microM MBP. Statistically significant enhancement was evident at 1 ng/ml and was maximal at 10 ng/ml. Preincubation with GM-CSF similarly enhanced MBP-induced histamine release. A 10- to 15-min preincubation with IL-5 maximally increased the level of MBP-stimulated histamine release. Preincubation of cells with 10 ng/ml IL-3 or IL-5 reduced the MBP concentrations required for histamine release by three- to fourfold and enhanced the rate of MBP-induced histamine release. MBP-stimulated histamine release before or after cytokine priming was independent of cytotoxicity as measured by 51Cr release. Consistent with a direct action of the cytokines on basophils, flow cytometric analysis demonstrated the presence of IL-3 and GM-CSF receptors on basophils. MBP also stimulated low levels of leukotriene C4 (LTC4) release from basophils of 84 to 99% purity, and experiments using enriched (18-63%) basophil preparations demonstrated that preincubation with IL-3, IL-5, and GM-CSF also potentiated MBP-stimulated leukotriene C4 release up to threefold in parallel with histamine release. These results indicate that IL-3, IL-5, and GM-CSF may contribute to the pathogenesis of allergic and other disorders characterized by eosinophilia in part through potentiation of basophil mediator release stimulated by MBP.
IL-10 production in cutaneous basal and squamous cell carcinomas. A mechanism for evading the local T cell immune response.
Authors: Kim J , Modlin R L , Moy R L , Dubinett S M , McHugh T , Nickoloff B J , Uyemura K 
Published: December 2022

Abstract
Cytokines play a vital role in the host immune response by regulating the development and function of immunocompetent cells. To explore the possibility that tumors may alter the host response via release of immunomodulatory cytokines, we studied two different skin cancers, basal cell carcinoma (BCC) and squamous cell carcinoma (SCC) as models. By RT-PCR, we found that the type 2 cytokines, IL-4 and IL-10, were strongly expressed in BCC compared with matched PBMC. Furthermore, IL-10 was more strongly expressed in SCC compared with benign growths. To identify the cell types responsible for production of these cytokines, tumor and tumor-infiltrating lymphocyte (TIL) cell lines were derived from BCC and SCC biopsy specimens. IL-2 and IFN-gamma mRNAs were expressed in TIL, while IL-10 mRNA were strongly expressed in BCC lines. In addition, IL-10 was detected in culture supernatants from BCC and SCC cell lines by ELISA and in tissue sections by immunohistology. TIL lines derived from these tumors demonstrated proliferative activity to autologous tumor cells in the presence of APCs, dependent on the addition of low concentrations of rIL-2 or neutralizing anti-IL-10 mAb in the culture medium. Furthermore, treatment of BCC with intralesional IFN-alpha induced tumor regression with concomitant up-regulation of IL-2 and down-regulation of IL-10 mRNA expression in lesions. These data suggest that tumor production of the cytokine, IL-10, may provide a mechanism for evading the local T cell-mediated immune response.
Molecular cloning of NKB1. A natural killer cell receptor for HLA-B allotypes.
Authors: D'Andrea A , Chang C , Franz-Bacon K , McClanahan T , Phillips J H , Lanier L L 
Published: December 2022

Abstract
The expression of certain MHC class I allotypes by potential target cells can inhibit NK cell-mediated cytotoxicity. We recently identified the NKB1 surface Ag, expressed on T and NK cell subsets, as a putative inhibitory receptor for HLA-B class I molecules possessing the Bw4 serologic epitope. NKB1 is a 70-kDa glycoprotein that after deglycosylation migrates as a 50-kDa protein as determined by SDS-PAGE. A cDNA encoding the NKB1 receptor was cloned from a NKB1+T cell cDNA library by expression in COS-7 cells using the anti-NKB1 mAb DX9. NKB1 is a member of the lg superfamily containing three lg-like domains in the extracellular region and is related to the recently identified family (p58/NKAT) of human NK and T cell surface molecules that appear to function as inhibitory receptors for HLA class I.
IL-4 plus CD40 monoclonal antibody induces human B cells gamma subclass-specific isotype switch: switching to gamma 1, gamma 3, and gamma 4, but not gamma 2.
Authors: Fujieda S , Zhang K , Saxon A 
Published: December 2022

Abstract
Stimulation with IL-4 plus CD40 mAb is known to induce production of IgE and IgG4. In this study, we determined the IgG subclass specificity of IL-4 plus CD40 mAb stimulation for human purified B cells. We determined true in vitro switching by the generation of switch circular DNA (S gamma/S mu) representing primary S mu/S gamma events and production of gamma subclass-specific germ-line transcripts by a combination of reverse transcription-PCR and restriction endonuclease digestion. We simultaneously measured changes in the levels of IgG subclass proteins produced. Forty-two clones of circular switch DNA were identified and sequenced. The IgG subclass of S gamma fragment in the S gamma/S mu chimeric PCR products was determined by analyzing key S gamma nucleotides. The switch-deleted clones were found to consist of S gamma 1/S mu, S gamma 3/S mu, and S gamma 4/S mu chimeric switch sequences, showing that such switching had occurred. No S gamma 2/S mu chimeric switch sequences were found. While a consensus sequence was not identified at the S gamma/S mu breakpoints, four contiguous guanines (GGGG) were noticeably present in the S gamma region near the breakpoint. The induction of gamma 1, gamma 3, and gamma 4 switch circles in human purified B cells was accompanied by enhanced production of IgG1, IgG3, and IgG4 but not IgG2. Similarly, stimulation with IL-4 alone induced gamma 1, gamma 3, and gamma 4 but not gamma 2 germ-line transcripts. These results demonstrate that IL-4 plus CD40 mAb induces Ig isotype switch from mu to gamma 1, gamma 3, and gamma 4 but not to gamma 2.
Marked conservation of complementarity-determining region 3 of the beta-chain of TCRs recognizing a mycobacterial heat shock protein 60-derived peptide with strong sequence similarity to human heat shock protein 60.
Authors: Goodall J C , Henwood J , Bacon P A , Gaston J S 
Published: December 2022

Abstract
The variable gene usage and sequence of human TCRs specific for a particular MHC/peptide combination have been investigated. The peptide comprises amino acids 456-466 of the 65-kDa Mycobacterium tuberculosis heat shock protein (hsp60), and is recognized in the context of HLA-DP. TCRs from both synovial fluid and peripheral blood (PB)-derived T cell clones used only five different V beta genes, three of which are closely related (V beta 6.7a, V beta 6.7b, and V beta 21.3). Among TCRs using these three genes there was marked conservation of the beta-chain sequence, whereby complementarity-determining region 3 (CDR3) contained an amino acid motif (*R*G*, amino acids 96-100) in association with either J beta 1.4 or J beta 2.5. These conclusions were strengthened by analysis of peptide-stimulated T cell lines that revealed not only TCR beta-chain sequences identical with those seen in T cell clones, but also additional beta-chains with similar CDR3 region sequences and J gene usage. In contrast, T cell lines derived by using IL-2 or a control peptide revealed variable usage of V beta and J beta genes; V beta 6.7a/b sequences from these lines and from freshly isolated PB did not contain the CDR3 motif noted in TCRs from Ag-specific T cells. We suggest that the remarkably limited diversity of TCRs noted in this study is a consequence of the similarity between the mycobacterial hsp60 peptide and the equivalent peptide from human hsp60, and reflects the trimming of the TCR repertoire required to maintain self-tolerance.
Initiation of the phosphocholine-specific response to Proteus morganii. B cell transfectants expressing unmutated VH/VL can respond to stimulation by P. morganii antigen.
Authors: Penner S J , George J , Claflin L 
Published: December 2022

Abstract
We wished to resolve a paradox of how the response to the phosphocholine (PC) determinant of Proteus morganii could be initiated from a precursor B cell whose receptor, in unmutated form as Ab, appears to be unable to bind Ag. Unmutated VH and unmutated VL constructs were co-transfected into the B cell lymphoma M12.4 to study stimulation via membrane lg (mlg). The same VH construct was expressed in an L+, H- hybridoma line to characterize Ab binding. The unmutated Ab showed no detectable binding in ELISA to the PC-containing Ag from P. morganii PC(PM). By contrast, the unmutated mlg mediated mobilization of calcium in response to the PC(PM) Ag. Single-positive B cell lines of mlgM, mlgD double-positive lines were all capable of responding. The degree of signaling depended greatly on high receptor number, and only a fraction of cells in the population responded. Inhibition of the PC(PM)-induced calcium response by free PC indicated that the response was Ag-specific. A transfectant B cell line expressing moderate levels of a high affinity, mutated mlgM readily responded to PC(PM). These observations indicate that the unmutated lg as a receptor is capable of interacting with PC(PM) and suggest that the immune response to PC(PM) could originate from the precursor B cell expressing the unmutated mlg. The role of mlgD vs mlgM is discussed in terms of the requirement for high receptor number in the signaling process.
Alloreactive 2C T cells recognize a self peptide in the context of the mutant Kbm3 molecule.
Authors: Tallquist M D , Pease L R 
Published: December 2022

Abstract
Previous studies hav shown that 2C T cells have dual specificity for Ld and Kbm3 alloantigens and are positively selected in the context of Kb. Analysis of Kbm3-eluted peptides reveals a single HPLC fraction that is a central component of the Kbm3 allodeterminant. Peptides with biologic and biochemical properties indistinguishable from those of the Kbm3 allopeptide were also isolated from Kb and Kbm8, despite the fact that cells bearing these class I molecules are not efficient targets for 2C T cells. The allopeptide was isolated and compared with p2Ca, the Ld allopeptide recognized by 2C T cells in the context of Ld. The Kbm3 allopeptide was found to be biochemically and functionally different from p2Ca. Therefore, the 2C TCR has dual specificity for two different peptides presented in the context of two structurally distinct class I molecules. The possibility of a common peptide being bound by Kb, Kbm3, and Kbm8 suggests that the peptide defined as an allodeterminant in the context of Kbm3 may also function in the positive selection of 2C T cells when presented in the context of Kb and Kbm8 during thymic development. In support of this view, the allopeptide was also found in Kb and Kbm8 thymic peptide eluates.