bluuebunny/crossref_metadata_2025 huggingface dataset:
Anti-tumor necrosis factor antibody therapy fails to prevent lethality after cecal ligation and puncture or endotoxemia.
Authors: Eskandari M K , Bolgos G , Miller C , Nguyen D T , DeForge L E , Remick D G
Published: December 2022

Cytokines have been studied intensively to delineate their role in the altered pathophysiology observed in septic shock. We studied the role of TNF in the lethality of two well characterized models of septic shock by inhibiting TNF's activity with a specific antibody. In the first model, sepsis was induced by cecal ligation and puncture (CLP), and in the second model sepsis was induced by either an i.p. or i.v. injection of LPS. After CLP, plasma endotoxin was detectable within 4 h and reached a peak at 8 h (136 +/- 109 ng/ml). TNF bioactivity peaked at 12 h (528 +/- 267 pg/ml) at a significantly higher level than sham-operated control mice (64 +/- 31 pg/ml). After i.p. LPS, TNF peaked much more quickly (90 min) compared with CLP and at a significantly higher level (107,900 +/- 25,000 pg/ml). Another cytokine studied in septic shock, IL-6, peaked at 12 h after CLP at 1011 +/- 431 pg/ml, and at 90 min after lethal LPS at 16,300 +/- 3,700 pg/ml. Mice were treated with an anti-TNF antibody that has been shown previously to inhibit in vivo TNF activity. Antibody treatment of mice subjected to CLP significantly reduced TNF bioactivity but did not reduce mortality or pulmonary neutrophilic infiltration. In the i.v. LPS model, anti-TNF antibody treatment concomitant with LPS injection reduced plasma TNF activity from 80,000 +/- 20,000 pg/ml to undetectable levels. However, anti-TNF treatment immediately before either i.v. or i.p. LPS did not reduce mortality. Additionally, when the antibody was administered 4 h before the lethal i.v. LPS, there was no reduction in lethality. These data show that in two separate models of septic shock blockade of TNF biologic activity will not prevent lethality.
Prostaglandin E2 and other cyclic AMP-elevating agents modulate IL-2 and IL-2R alpha gene expression at multiple levels.
Authors: Anastassiou E D , Paliogianni F , Balow J P , Yamada H , Boumpas D T
Published: December 2022

cAMP is an intracellular second messenger that conveys inhibitory signals for T cell activation and clonal proliferation. cAMP also inhibits the production of IL-2 and IL-2R alpha-chain expression. To determine the mechanisms of this inhibition, human peripheral blood T lymphocytes were stimulated with anti-CD3 mAb, PHA, PMA, or ionomycin, alone or in combination. cAMP elevation by PGE2, cholera toxin, or the cell-permeable analogue 8-bromo-cAMP inhibited the tyrosine phosphorylation of a protein of 100 kDa. This inhibition was associated with decreased IL-2 production and IL-2R alpha expression at both the protein product and the mRNA levels. Nuclear run-off assays showed that the inhibitory effect of cAMP on IL-2 and IL-2R alpha gene expression is mediated at the transcriptional level. H-8, an inhibitor of protein kinase A, reversed the inhibitory effect of cAMP on nuclear transcription of the IL-2 gene, suggesting that this is mediated through activation of protein kinase A. Post-transcriptionally, cAMP elevation decreased the t1/2 of IL-2 mRNA by more than 50%. These data indicate that cAMP inhibits cell membrane, cytoplasmic, and nuclear events associated with T cell activation and highlight the complexities of its action of lymphocyte function.
Heparin enhances the interaction of infective Leishmania donovani promastigotes with mouse peritoneal macrophages. A fluorescence flow cytometric analysis.
Authors: Butcher B A , Sklar L A , Seamer L C , Glew R H
Published: December 2022

Human visceral leishmaniasis results from the infection of macrophages by the protozoan parasite Leishmania donovani. Both forms of the parasite, the extracellular promastigote and the obligate intracellular amastigote, require cell surface molecules to ensure their recognition and uptake by the host cell, the macrophage. We have proposed previously that the heparin-binding protein on the surface of promastigotes is an adhesion molecule. The present report provides experimental evidence to support this hypothesis. Fluorescence flow cytometry using FITC-heparin was employed to study the heparin-binding protein of L. donovani promastigotes and amastigotes. We demonstrate the presence of the heparin-binding protein on the surface of amastigotes and document the heparin specificity of the binding protein for both forms of the parasite. Two-color fluorescence analysis was performed to compare R-PNA reactivity and FITC-heparin binding during the parasite's 7-day growth curve. Using this strategy we show that the expression of heparin binding activity coincides with the differentiation of the noninfective promastigote into the infective metacyclic from of the parasite. Macrophages that were challenged for 30 min with heparin-treated, FITC-labeled parasites became 2.82-fold more fluorescent than their counterparts which were exposed to non-heparin-treated FITC-labeled promastigotes. Finally, using Kolmogorov-Smirnov analysis we show that the adhesion of promastigotes to mouse peritoneal macrophages is significantly enhanced in the presence of 3.3 microM heparin. The experiments described in the present report provide evidence for the hypothesis that L. donovani's heparin-binding protein is a virulence factor that functions as an adhesion molecule in the parasite-macrophage interaction.
A novel IgA receptor expressed on a murine B cell lymphoma.
Authors: Rao T D , Maghazachi A A , González A V , Phillips-Quagliata J M
Published: December 2022

The specificity and properties of a novel IgA receptor expressed on the surface of a tissue culture-adapted B cell lymphoma, T560, that originated in murine gut-associated lymphoid tissue, have been explored. Like the IgA receptors of murine T and splenic B cells studied by others, the T560 IgA receptor is trypsin sensitive and neuraminidase resistant and is up-regulated on T560 cells by exposing them overnight to high concentrations of polymeric IgA. Unlike them, the T560 IgA receptor is inhibited by low concentrations of IgM and high concentrations of IgG2a and IgG2b, binds at pH 4.0 but not at pH 8.0, is down-regulated by activation of protein kinase C and is sensitive to phosphatidylinositol-specific phospholipase C, indicating that it is glycosyl phosphatidylinositol-linked to the cell membrane. It is not a cell-bound form of galactosyl transferase, does not appear to bind to Ig through carbohydrate residues and does not react specifically with antibody to secretory component. It may be a completely new, cross-reactive receptor, perhaps related in some way to the polymeric Ig receptor or to the receptor for IgA expressed on the apical surface of Peyer's patch M cells, which is known to cross-react with IgG. Alternatively, it may be homologous to the highly IgA-specific Fc alpha R of T cells but, perhaps because of its glycosyl phosphatidylinositol linker, may have an ability to move and interact with other Ig receptors on the cell surface such that Ig bound to them are cross-inhibitory.
R1-20, a novel monoclonal antibody reacting with a molecule distinct from integrin family, induces homotypic cell aggregation.
Authors: Nakamura S , Imanishi J , Minowada J
Published: December 2022

R1-20, a novel mAb reacting with a cell surface Ag on normal human lymphocytes and leukemic cell lines, was shown to induce homotypic cell aggregation in leukemic cell lines. This phenomenon was specific to mAb R1-20 because antibodies recognizing CD2, CD7, CD28, and HLA-ABC failed to exhibit homotypic cell aggregation. Induction of aggregation by mAb R1-20 occurred at 37 degrees C, but not at 4 degrees C and required cytoskeletal integrity. Sodium azide, a metabolic inhibitor, had no effect on the aggregation. Distinct from lymphocyte function-associated Ag-1/intercellular adhesion molecule-1 interaction in which divalent cations are essential elements, R1-20-mediated aggregation was not abolished with EDTA treatment. The R1-20 Ag was determined as a molecule of M(r) 100 to 110 kDa in immunoprecipitation and immunoblotting methods, under both reducing and nonreducing conditions. The molecular composition is quite different from that of any known integrin molecule. The R1-20 Ag was expressed on resting and activated T Lymphocytes as well as on normal B lymphocytes. Monocytes and granulocytes had no detectable R1-20 Ag. Among the leukemia-derived cell lines we used, mAb R1-20 reacted with 18 of 32 T cell lines, 2 of 20 B cell lines, 2 of 3 non-T-non-B cell lines, 2 of 7 myelomonocytic cell lines, and 2 of 3 nonlymphoid-nonmyeloid cell lines. All EBV-transformed B cell lines examined (10 cell lines) were R1-20+. The spectrum of reactivity among the cell lines tested was different from that of known antiadhesion antibodies tested. All these findings indicate that the Ag recognized by mAb R1-20 may represent a new type of cell adhesion molecule.
Induction and suppression of delayed-type hypersensitivity to non-MHC antigens during lethal graft-versus-host reaction.
Authors: Pritchard L L , Huchet R , Bruley-Rosset M , Riché N , Mishal Z , Halle-Pannenko O
Published: December 2022

A delayed-type hypersensitivity reaction (DTH) to non-MHC Ag was detected during a lethal graft-vs-host reaction (GVH) induced by incompatibility for non-MHC Ag alone. In this model, when appropriate doses of B10.D2 bone marrow and lymphoid cells are grafted to irradiated (DBA/2 x B10.D2)F1 recipients, the ensuing GVH, directed against those DBA/2 non-MHC Ag absent from the B10.D2 background, results in virtually 100% mortality in less than 3 mo; donor alloimmunization against the host histocompatibility Ag considerably reduces mortality, and survival rates of 80 to 100% are common. The experiments reported here show that: 1) the cell responsible for DTH induction expresses the CD4+ CD8- phenotype; 2) CD4+ cells likewise seem to play a predominant role in the pathology of lethal GVH in this genetic combination; 3) the alloimmunization protocol that abrogates mortality also abolishes GVH-associated DTH; and 4) this suppressive effect, as shown elsewhere for the protection against mortality, is mediated by CD4- CD8- "double negative" Thy-1+ CD3+ T suppressor cells. Thus, there is a good parallel between lethal GVH and its associated DTH as concerns both induction and suppression of the two phenomena, suggesting that mortality and DTH may represent different manifestations of a common underlying mechanism. Initiation of the effector phase of DTH in the adoptive transfer model seems to be dependent on the presence of a Thy-1+ double-negative cell in the transfer inoculum; the possible relationship of this double-negative cell to the Th-1-type CD4+ DTH-mediating cell recently shown to induce lethal GVH is discussed.
Analysis of CD4+ T cells that provide contact-dependent bystander help to B cells.
Authors: Croft M , Swain S L
Published: December 2022

Although cognate, MHC-restricted interaction of Th cells with Ag-presenting B cells provides effective help to a resting B cell, substantial B cell responses have also been seen with preactivated T cell clones that cannot recognize Ag on the B cell but apparently interact in a noncognate fashion (the bystander response). Here, we have investigated the ability of distinct Th cell subsets and T cells activated by different stimuli to support such bystander B cell responses. We have also determined which cytokines are involved. We generated distinct CD4+ T cell subsets specific for both alloantigen (using normal mice) and cytochrome c (using TCR transgenic mice). To compare cognate and bystander help, we analyzed the response of allogeneic (cognate) vs syngeneic (bystander) resting B cells in the former case, and the response of syngeneic B cells in the presence vs absence of Ag, in the latter case. Both approaches gave similar results. T cells stimulated with Ag for 24 h (naive and memory cells) or generated from naive cells over 4 days in the presence of exogenous IL-2 ("Th1-like" effectors) induced B cells to secrete minimal amounts of bystander Ig (20 to 700 ng/ml), less than 6% of the Ig induced under cognate conditions. In contrast, effectors generated in IL-4 or IL-6 ("Th2-like" and "Th0-like") induced significantly more bystander Ig (4 to 9 micrograms/ml), which was 18 to 30% of the amount produced during a cognate response. Restimulation of Th cell populations with anti-CD3, instead of Ag/APC, enhanced their ability to induce bystander Ig to levels 40 to 100% of those produced through cognate interaction. The addition of anti-cytokine Ab to bystander responses indicated that the cytokines utilized were similar to those mediating response after cognate interaction. Addition of exogenous cytokines did not specifically enhance the extent of the bystander response as a function of the cognate response. These results suggest that most Th cells can efficiently activate only those B cells that present relevant Ag on class II MHC, but that highly activated/differentiated Th effectors also have the ability to induce significant bystander B cell responses through noncognate interactions. We also conclude that the mode of Th cell activation and the cytokines encountered during Th differentiation play a major role in the capacity of helper cells to initiate a bystander response.
EBV/C3d receptor (CR2) interacts by its intracytoplasmic carboxy-terminal domain and two distinct binding sites with the p53 anti-oncoprotein and the p68 calcium-binding protein.
Authors: Frade R , Gauffre A , Hermann J , Barel M
Published: December 2022

EBV/C3d receptor (CR2) interacts with the p53 anti-oncoprotein expressed in the human B lymphoma cells, Raji but not in normal B cells, and with the p68 calcium-binding protein, expressed in normal B lymphocytes but not in transformed B lymphocytes. To characterize the CR2 domain interacting with these two intracellular proteins, we synthesized a 34-amino acid peptide, pep34, corresponding to its intracytoplasmic carboxy-terminal domain and analyzed its binding and antigenic properties. Binding of 125I-labeled p53 or 125I-labeled p68 on immobilized pep34 was specific, additive, and totally inhibited by unlabeled p53 or p68, respectively, but not by unlabeled p68 or p53, respectively. Antigenic properties of pep34 were analyzed by immunizing rabbits with particle-bound pep34. Polyclonal anti-pep34 Ab carried anti-CR2 specificities that recognized only the intracellular domain of CR2. In addition, anti-pep34 Ab also carried anti-p53 or anti-p68 specificities. Anti-p53 or anti-p68 specificities were not due to putative common structural or conformational antigenic determinants between the pep34 synthetic peptide and the p68 or p53 proteins. These anti-p53 and anti-p68 specificities were identified as anti-idiotypic anti-CR2 Ab mimicking either p53 or p68 binding sites of CR2. These data clearly establish that despite its short length, the intracytoplasmic C-terminal tail of CR2 is involved in direct protein-protein interactions with the two intracellular regulatory proteins, p53 and p68. An additional feature of these data is the demonstration that particle-bound pep34 triggered "in vivo" anti-Id Ab restricted to either p53 or p68 specificities.
Characteristics of murine monoclonal anti-CD4. Epitope recognition, idiotype expression, and variable region gene sequence.
Authors: Lohman K L , Attanasio R , Buck D , Carrillo M A , Allan J S , Kennedy R C
Published: December 2022

We have characterized a series of mouse monoclonal anti-CD4 and describe both their CD4 epitope recognition and Id expression. We also determined the V region gene sequences of these antibodies in an attempt to correlate epitope recognition and Id expression with V region sequence. All of these preparations recognize epitopes that cluster around the HIV gp120 binding site on the human CD4 molecule. However, we observed differences in epitope recognition among the anti-CD4 preparations, based on either competitive inhibition assays or functional assays, such as syncytium inhibition. Analysis of Id specificities using a polyclonal anti-Id generated against anti-Leu 3a indicated that five of the seven monoclonal anti-CD4 expressed a shared Id. Based on V region gene sequences, the V region kappa-chain (V[kappa]) from each of the seven antibodies was encoded by the V[kappa]21 gene family and expressed the J[kappa]4 gene segment. Those preparations that expressed the shared Id with anti-Leu 3a have virtually identical V[kappa] sequences, with a high degree of homology in the CDR. The VH region gene sequences of six of the seven antibodies also shared overall homology and appeared to be encoded by the J558 VH gene family. The seventh anti-CD4 VH region is encoded for by the VHGAM gene family. The majority of these antibodies used JH3 gene segment, although the JH2 and JH4 gene segments were also represented. In addition, several of these antibodies share a common sequence organization within their V-D-J joining regions that appears to involve N and P sequences to generate unique D segments. Together, these data suggest that differences in epitope recognition among the monoclonal anti-CD4 may reflect sequence variability primarily within the CDR3 region of both V[kappa] and VH. The basis for the detection of a shared Id most likely reflects the high degree of homology within the V[kappa] region sequences. In addition, these data, which are based on a limited analysis, suggest the possible restricted use of V region germ-line gene families in the secondary antibody response of BALB/c mice to specific epitopes on the human CD4 molecule.
A stimulatory Mls-1 superantigen is destroyed by ultraviolet light while other Mtv-7 antigens remain intact. Significance for Mls-1 unresponsiveness.
Authors: Dannecker G , Mecheri S , Clarke K , Dudhane A , Wang Z Q , Hoffmann M K
Published: December 2022

Accessory cells present Ag together with costimulatory signals as immunogens and without costimulatory signals as tolerogens. Responsiveness and unresponsiveness are thus alternatives of T cell immune reactions to Ag. Superantigens appear to make an exception; being presented by accessory cells capable of providing costimulatory signals, these Ag induce a strong T cell response but leave T cells unresponsive to a secondary challenge (anergy). We show here that T cell anergy is not a mandatory consequence of superantigen-induced activation. Mls-1- BALB/c recipients of DBA/2 spleen cells mount vigorous Mls-1 responses in vivo but their T cells retain the ability to respond to a subsequent Mls-1 challenge in vitro. We tested the possibility that the inability of DBA/2 spleen cells to inactivate Mls-1-reactive BALB/c T cells was the result of excessive costimulatory activity provided by Mls-1+ DBA/2 B cells. Costimulatory accessory cell activity has been reported to be destroyed by UV light. We exposed superantigen-presenting cells to UV radiation and found that they had lost the ability to stimulate an Mls-1 response without, however, gaining the capacity to render Mls-1-specific T cells anergic. Despite their inability to noticeably stimulate Mls-1-reactive T cells, UV-treated Mls-1+ lymphocytes induced an absolute unresponsiveness in Mls-1- recipients to a second challenge with the superantigen. Our data are in agreement with previous evidence, confirmed here, that BALB/c mice establish immunity against Mls-1+ cells, which causes the accelerated rejection of superantigen-bearing lymphocytes. Thus, our data imply that, whereas it takes stimulatory superantigenic Mtv-7 gene products to induce the activation of superantigen-reactive T cells, nonsuperantigenic Mtv-7 gene products may induce an immune response leading to the elimination of Mtv-7+ lymphoid cells.
Bromelain treatment of human T cells removes CD44, CD45RA, E2/MIC2, CD6, CD7, CD8, and Leu 8/LAM1 surface molecules and markedly enhances CD2-mediated T cell activation.
Authors: Hale L P , Haynes B F
Published: December 2022

Treatment of T cells with the cysteine protease bromelain has been widely used to enhance the binding of human T cells to human E (autologous E rosettes) and has been shown to remove surface T cell CD44 molecules. Ligand binding to CD44 has been shown to markedly augment T cell activation. To study the activation potential of bromelain-treated CD44 T cells, we have compared the proliferation of sham- and bromelain-treated normal human PBMC to mitogenic CD2 mAb. We found that bromelain not only removed T cell CD44, but also removed the CD45RA isoform of CD45 as well as E2/MIC2, CD6, CD7, CD8, and Leu 8/LAM1 molecules. T cell proliferation in response to CD2 mAb was increased 325% in bromelain-treated PBMC compared to sham-treated PBMC (p < 0.005). Reciprocal treatment experiments using purified T cells and monocytes demonstrated that the enhancement of T cell CD2 activation by bromelain occurred only when T cells were treated with bromelain and was accompanied by increased adhesion of T cells to monocytes. These data demonstrate that expression of portions of the extracellular domains of the CD44, CD45RA, E2/MIC2, CD6, CD7, CD8, and Leu 8/LAM1 surface molecules are not required for CD2 activation of human T cells. Rather, the removal of these surface molecules by bromelain is associated with enhanced T cell-monocyte aggregation and enhanced CD2-mediated T cell activation. Taken together with data that CD44, E2/MIC2, CD6, and CD7 mAb inhibit CD2/lymphocyte function-associated Ag-3-mediated cellular interactions and also augment CD2-mediated triggering of T cells, these data suggest that members of the bromelain-sensitive group of surface molecules may comprise a set of CD2-associated adhesion ligands that acts in concert to modulate human T cell activation.
Role of antigen-specific T cell help in the generation of in vivo antibody responses. II. Sustained antigen-specific T cell help is required to induce a specific antibody response.
Authors: Finkelman F D , Villacreses N , Holmes J M
Published: December 2022

The injection of mice with a goat or rabbit antibody to mouse IgD stimulates a large polyclonal IgG response, approximately 10% of which is specific for antigenic determinants on the anti-IgD antibody molecule. The large goat IgG (GIgG)-specific antibody response in mice injected with goat antibody to mouse IgD requires that GIgG-specific B cells undergo much greater clonal expansion than B cells specific for other Ag. One possible explanation for the greater clonal expansion of GIgG-specific B cells is that B cells that lack GIgG specificity can only be stimulated with GIgG-specific T help during the relatively short time that anti-IgD binds to, and is processed and presented by, these B cells before they cease to express membrane mIgD. In contrast, GIgG-specific B cells can continue to bind, process, and present GIgG through mIgM after they lose mIgD. To test the hypothesis that extended stimulation with Ag-specific T help is required to generate a specific antibody response, we determined time requirements for Ag-specific T cell help for the development of such a response. Mice were injected with rabbit antibody to mouse IgD plus one or more daily injections of FITC conjugated to a F(ab')2 fragment of rabbit IgG (FITC-(Fab')2), which has a short in vivo half-life, and IgG1 anti-FITC antibody production was analyzed. In this system, each additional injection of FITC-F(ab')2 extends the period during which FITC-specific B cells can process this Ag and present it to rabbit IgG-specific T cells. Each additional injection of FITC-F(ab')2 stimulated a several-fold increase in IgG1 anti-FITC antibody levels, and injections on 5 consecutive days were required to induce a maximal anti-FITC response. These observations provide evidence that sustained Ag-specific T cell help is required to stimulate the degree of B cell clonal expansion that characterizes a specific antibody response.
Genomic structure and chromosomal mapping of the murine CD40 gene.
Authors: Grimaldi J C , Torres R , Kozak C A , Chang R , Clark E A , Howard M , Cockayne D A
Published: December 2022

The B cell-associated surface molecule, CD40, is likely to play a central role in the expansion of Ag-stimulated B cells, and their interaction with activated Th cells. In our study we have isolated genomic clones of murine CD40 from a mouse liver genomic DNA library. Comparison with the murine CD40 cDNA sequence revealed the presence of nine exons that together contain the entire murine CD40 coding region, and span approximately 16.3 kb of genomic DNA. The intron/exon structure of the CD40 gene resembles that of the low affinity nerve growth factor receptor gene, a close homolog of both human and murine CD40. In both cases the functional domains of the receptor molecules are separated onto different exons throughout the genes. Southern blot analysis demonstrated that murine CD40 is a single copy gene that maps in the distal region of mouse chromosome 2.
Role of colony-stimulating factor-1 in macrophage activation in tumor-bearing mice.
Authors: Sakata T , Iwagami S , Tsuruta Y , Teraoka H , Suzuki S , Suzuki R
Published: December 2022

We previously reported a dramatically increased number of macrophages in tumor-bearing mice. In this study, we investigated the involvement of CSF in that phenomenon. CSF-1 responding cells as macrophages precursors increased significantly in number in the spleens of tumor-bearing mice as compared with those in normal mice. Splenic cells and sera from the tumor-bearing mice respectively expressed CSF-1 in mRNA and serum protein levels, but failed to express the other CSF (granulocyte-macrophage-CSF or IL-3). Nonadherent splenic mononuclear cells (< 0.5% macrophages) from normal mice proliferated and differentiated into mature macrophages in culture within 7 days with recombinant mouse CSF-1 (rCSF-1). Both macrophages harvested from tumor-bearing mice and those activated in vitro with rCSF-1 expressed mostly Mac-1, -2 (and -3) Ag, showed yeast phagocytosis, produced IL-1 but not IL-2 or IL-3, and displayed potent cytotoxicity against NK cell resistant Meth-A tumor cells. These macrophages also expressed lipocortin I mRNA and secreted lipocortin I protein, and suppressed mitogenic responses of splenic lymphocytes. rCSF-1-activated macrophages derived from nonadherent splenic cells expressed both CSF-1 and CSF-1 receptor (c-fms) mRNA. Administration of rCSF-1 into normal mice induced hemopoietic and immunologic alternations similar to those observed in tumor-bearing mice. These results suggest that CSF-1 is involved in the dramatic increase of macrophages in tumor-bearing mice, possibly through an autocrine or paracrine loop.
Collagen-induced arthritis in rats. Examination of the epitope specificities of circulating and cartilage-bound antibodies produced by outbred and inbred rats using cyanogen bromide-derived peptides purified from heterologous and homologous type II collagens.
Authors: Cremer M A , Terato K , Watson W C , Griffiths M M , Townes A S , Kang A H
Published: December 2022

To determine the number and location of antibody binding epitopes on type II collagen, outbred and inbred rats were immunized with chick, bovine, human, and rat type II collagen (CII, BII, HII, and RII); all sera were assayed for reaction with a panel of CB peptides purified and renatured from the immunizing collagen and from RII. Antibody reaction patterns (profiles) varied among individual outbred rats but were essentially constant over time and changed little after boosting. The strongest antibody reactions were to CB11, CB9-7, and CB12 followed by CB8, CB10, and CB6. Antibody profiles varied depending on the species of collagen used for immunization and the strain of rat immunized. Except for CB10, where antibodies were largely specific for heterologous collagens, antibodies reactive with all other CB peptides cross-reacted strongly with renatured rat CB peptides. Sera from inbred BB rats immunized with BII, CII, or HII reacted best with CB11, unlike antisera to RII that reacted strongly with CB9-7. Inbred LEW, COP, WKY, F344, and BUF rats immunized with BII reacted strongest with CB9-7 and variably with CB11 and CB12. BBxLEW F1 hybrid rats reacted almost equally with CB11 and CB9-7 producing an antibody profile intermediate to those elicited in the parent strains. Finally, antibodies reactive with rat CB11, CB9-7, and CB12 could be eluted from normal rat cartilage incubated in anti-BII serum; antibody eluate profiles generally paralleled the profile produced by the sera applied to cartilage. Taken together, these findings indicate that multiple antibody-reactive epitopes on type II collagen may be instrumental in the initiation of collagen-induced arthritis in rats, particularly shared or cross-reactive epitopes located within CB11, CB9-7, CB12, and CB8.
Restoration of T cell receptor-mediated signal transduction by transfection of CD45 cDNA into a CD45-deficient variant of the Jurkat T cell line.
Authors: Koretzky G A , Kohmetscher M A , Kadleck T , Weiss A
Published: December 2022

The TCR is a multimeric structure comprised of distinct Ag recognition and signal transduction components. Although none of the molecules that make up the TCR possess intrinsic protein tyrosine kinase (PTK) activity, stimulation of T cells via the TCR results in the rapid appearance of newly tyrosine phosphorylated proteins in cell lysates. Evidence suggests ligation of the TCR induces activation of a PTK that may be a member of the src family. One early consequence of this TCR-mediated PTK activation is the phosphorylation of the gamma 1 isoform of phospholipase C. This phosphorylation event is associated with increased enzymatic activity resulting in the hydrolysis of phosphatidylinositol 4,5 bisphosphate into two second messengers, inositol 1,4,5 trisphosphate and diacylglycerol. Recently, our laboratory and others have isolated mutant T cells that lack surface expression of CD45, the major surface tyrosine phosphatase expressed on lymphoid cells. Stimulation of the TCR on these cells fails to result in the expected activation events. We demonstrate that reconstitution of surface expression of the 180-kDa isoform of CD45 by gene transfer into a CD45-deficient mutant of the Jurkat T cell leukemic line restores the ability of the TCR to couple fully to its signal transduction machinery. These results support the role of CD45 tyrosine phosphatase activity in regulating the TCR-activated PTK.
Participation of the CD27 antigen in the regulation of IL-2-activated human natural killer cells.
Authors: Sugita K , Robertson M J , Torimoto Y , Ritz J , Schlossman S F , Morimoto C
Published: December 2022

The CD27 Ag is expressed by the majority of resting T lymphocytes and appears to play a crucial role in T cell activation. We found that some resting peripheral blood NK cells also express CD27. Furthermore, CD27 expression was up-regulated on NK cells stimulated by IL-2. The cytolytic activity of IL-2-activated, but not resting, NK cells was inhibited by an anti-CD27 mAb (anti-1A4). However, anti-1A4 did not affect conjugate formation between IL-2-activated NK cells and tumor cell targets. In contrast, anti-1A4 inhibited CD2-mediated calcium mobilization and the serine esterase activity of NK cell granules. These inhibitory effects could be mediated in part by increase in intracellular cAMP levels induced by anti-1A4. Our results suggest that the CD27 Ag plays an important role in the regulation of activated NK cells.
Superantigen-mediated human monocyte-T lymphocyte interactions are associated with an MHC class II-, TCR/CD3-, and CD4-dependent mobilization of calcium in monocytes.
Authors: Damaj B , Mourad W , Naccache P H
Published: December 2022

The present study was designed to examine the potential involvement of calcium ions as second messengers in the mediation of the staphylococcal enterotoxin A (SEA)/MHC class II-induced activation of human monocytes. Treatment of monocytes with a monomeric form of SEA failed to induce detectable changes in the level of intracellular calcium in either monocytes or THP-1 cells. However, cross-linking of SEA with biotin-avidin induced a rapid and transient increase in calcium levels in monocytes and in INF-gamma-treated THP-1 cells. This artificial cross-linking system was reproduced by natural physiologic ligands expressed on the surface of T lymphocytes. Delayed, transient, and concentration (cell as well as toxin)-dependent increases in the cytoplasmic level of free calcium in SEA-treated monocytes were observed upon the addition of autologous resting T cells or purified CD4+ cells, but not of CD8+ cells, B cells, or neutrophils. Antibodies against MHC class II Ag, TCR/CD3, and CD4 molecules inhibited the SEA-dependent interaction between monocytes and T cells as indicated by significant decreases in the rise of calcium levels observed in monocytes. Anti-CD8 and anti-class I antibodies did not affect the interaction between the monocytes and the T cells and failed to alter the calcium response. Taken together, these results suggest that the SEA-induced, T cell-dependent calcium mobilization in monocytes requires physical interactions between SEA-MHC class II, TCR/CD3, and CD4 molecules. The ability to mediate a T cell-dependent calcium increase in monocytes was shared by several enterotoxins including staphylococcal enterotoxin B and toxic shock syndrome toxin-1. The characteristics of the SEA-mediated calcium mobilization in monocytes strongly support the hypothesis that this response is an integral part of the signal transducing machinery linked to MHC class II molecules.
Human recombinant soluble decay accelerating factor inhibits complement activation in vitro and in vivo.
Authors: Moran P , Beasley H , Gorrell A , Martin E , Gribling P , Fuchs H , Gillett N , Burton L E , Caras I W
Published: December 2022

Complement plays a role in activating the inflammatory response and has been implicated in the pathogenesis of some inflammatory diseases. With a view toward controlling unwanted C activation, we evaluated the C regulator, human decay accelerating factor (DAF). Three forms of recombinant DAF were purified from transfected Chinese hamster ovary cells: glycophosphatidylinositol (GPI)-linked membrane DAF (mDAF) extracted from cell membranes; spontaneously shed soluble DAF (sDAF) derived from mDAF; and a novel secreted protein (seDAF), generated by deletion of the signal for GPI attachment. We show that all three molecules inhibit both the classical and alternative pathways of C activation. The following observations indicate that mDAF extracted from Chinese hamster ovary cells reincorporates into RBC membranes via its GPI anchor: 1) cells that are preincubated with mDAF and then washed remain fully protected from C-mediated hemolysis; 2) incubation with phosphatidylinositol-specific phospholipase C abolishes this protection; and 3) sDAF and seDAF, which lack a GPI anchor, do not associate with cell membranes. mDAF is a more potent inhibitor of C-mediated hemolysis than either sDAF or seDAF, suggesting that incorporation into cell membranes greatly enhances the efficiency with which DAF inhibits C activation on the cell surface. In contrast, C activation in the fluid phase is inhibited by sDAF and seDAF, but not by mDAF, possibly due to interference by serum lipoproteins. A reversed passive Arthus reaction in guinea pigs was used to evaluate the ability of recombinant seDAF to inhibit C activation in vivo. When administered at dermal sites, seDAF reduced the severity of immune complex-mediated inflammatory reactions induced by a reversed passive Arthus reaction, as judged by both gross and histologic examination. These data indicate that seDAF may be useful as an anti-inflammatory therapeutic.
Platelet-activating factor as an intercellular signal in neutrophil-dependent platelet activation.
Authors: Zhou W , Javors M A , Olson M S
Published: December 2022

The role of platelet-activating factor (PAF) in heterotypic cell to cell interactions in a rabbit neutrophil-platelet mixture model was investigated. Platelets were exposed to each of three chemotactic agonists: PAF, leukotriene B4 (LTB4), or FMLP. Only PAF stimulated aggregation, [3H]serotonin secretion, and cytosolic Ca2+ mobilization in platelets alone. However, platelets were stimulated by LTB4 and FMLP in the presence of neutrophils. This neutrophil-dependent platelet activation was blocked by pretreatment of platelets with PAF receptor antagonists, and was prevented by desensitization of platelets to PAF. Furthermore, the time-course of platelet activation showed a positive correlation with PAF production by neutrophils stimulated with either LTB4 or FMLP. The PAF-mediated neutrophil-platelet interaction was dependent on direct cell to cell contact, as demonstrated by experiments in which the majority of newly formed PAF was neutrophil associated (rather than released). Platelet activation did not occur when the neutrophil-platelet mixture was not stirred, minimizing cell to cell contact, or when platelets were challenged with a cell-free supernatant prepared from neutrophils activated with LTB4 or FMLP. Finally, the neutrophil-platelet interaction was abolished by SC-49992, a peptidomimetic of the fibrinogen binding sequence Arg-Gly-Asp-Phe, indicating a Arg-Gly-Asp-specific recognition mechanism. Our results demonstrate that neutrophil-generated PAF plays a crucial role in neutrophil-dependent platelet activation in this model system. This type of intercellular signaling event may be important in certain inflammatory or thrombotic processes.
Accelerated programmed cell death of MRL-lpr/lpr T lymphocytes.
Authors: Van Houten N , Budd R C
Published: December 2022

MRL-lpr/lpr (lpr) mice develop a polyclonal accumulation of abnormal peripheral T lymphocytes, which bear surface alpha beta TCR, CD3, and the B220 isoform of CD45, but lack CD4, CD8, and CD2. These T cells have a constitutively phosphorylated CD3 zeta chain and manifest a defect in signal transduction that results in a lack of IL-2 production and proliferation. We investigated whether this signaling abnormality might contribute to their accumulation via a defect in T cell elimination in the periphery. T cell deletion occurs through a process of programmed cell death with DNA degradation, or apoptosis. Viable lymphocytes from lpr mice were found to undergo rapid programmed cell death in culture within 4 h without additional activation, which was not observed in lymphocytes from normal MRL-+/+ or C57BL/6-+/+ mice. Both nonmature B220+ and mature B220- T lymphocytes from lpr mice display this accelerated programmed cell death, indicating that this is a defect affecting all peripheral T lymphocytes in lpr mice. In vitro apoptosis of lpr T cells could be inhibited with PMA, a stimulator of protein kinase C. Thus, the massive accumulation of T lymphocytes in the lymphoid tissue of lpr mice is not due to a defect in their ability to undergo programmed cell death in vitro. The activation state of lpr T cells may contribute to their rapid degradation of DNA in vitro.
IL-4 and IFN (alpha and gamma) exert opposite regulatory effects on the development of cytolytic potential by Th1 or Th2 human T cell clones.
Authors: Parronchi P , De Carli M , Manetti R , Simonelli C , Sampognaro S , Piccinni M P , Macchia D , Maggi E , Del Prete G , Romagnani S
Published: December 2022

The cytolytic potential of a total number of 118 CD4+ human T cell clones specific for purified protein derivative (PPD) from Mycobacterium tuberculosis, tetanus toxoid, Lolium perenne group I allergen (Lol p I), Poa pratensis group IX allergen (Poa p IX), or Toxocara canis excretory/secretory antigen(s) (TES) was assessed by both a lectin (PHA)-dependent and a MHC-restricted lytic assay and compared with their profile of cytokine secretion. The majority of clones with Th1 or Th0 cytokine profile exhibited cytolytic activity in both assays, whereas Th2 clones usually did not. There was an association between the cytolytic potential of T cell clones and their ability to produce IFN-gamma, even though IFN-gamma produced by T cell clones was not responsible for their cytolytic activity. IL-4 added in bulk culture before cloning inhibited not only the differentiation of PPD-specific T cells into Th1-like cell lines and clones, but also the development of their cytolytic potential. The depressive effect of IL-4 on the development of PPD-specific T cell lines with both Th1 cytokine profile and cytolytic potential was dependent on early addition of IL-4 in bulk cultures. In contrast, the addition in bulk culture of IFN-gamma enhanced both the cytolytic activity of PPD-specific T cell lines, as well as the proportion of PPD-specific T cell clones with cytolytic activity. The addition in bulk cultures before cloning of IFN-gamma or IFN-alpha favored the development of TES-specific and Poa p IX-specific T cells into T cell clones showing a Th0 or even a Th1, rather than a Th2, cytokine profile. Accordingly, most of TES- and Poa p IX-specific T cell clones derived from cultures containing IFN-gamma or IFN-alpha displayed strong cytolytic activity. These data indicate that the majority of human T cell clones that produce IFN-gamma, but not IL-4 (Th1-like), as well as of T cell clones that produce IFN-gamma in combination with IL-4 (Th0-like) are cytolytic. More importantly, they demonstrate that the addition of IFN (alpha and gamma) or IL-4 in bulk cultures before cloning may influence not only the cytokine profile of human CD4+ T cell clones but also their cytolytic potential.
The Effect of Ricinoleated Vaccine of the Hemolytic Streptococcus (Scarlet Fever) on Animals
Authors: Kozlowski Anthony
Published: December 2022

Of the many different substances which have been tried in detoxifying bacterial toxins for the purpose of immunization, sodium ricinoleate has recently been suggested as very suitable (1–6). Thus, it has also been reported that broth toxin from a culture of the hemolytic streptococcus (scarlet fever) when mixed with sodium ricinoleate and injected intramuscularly into man did not induce any severe reaction such as usually follows an administration of the same amount of untreated broth toxin; moreover, after the elapse of a certain time, the intracutaneous test became negative in a large percentage of cases.

To gain some insight into the efficacy of soap-vaccine and into the mechanism of soap action, the following experiments have been carried out on mice.

Method. Sodium ricinoleate was prepared from castor oil saponified by alcoholic potassium hydroxide and purified by cooling, by fractionation of its potassium, sodium, and barium salts by the method described in another paper which will be published later.
The Zonal Action of Antiserum in Pneumococcus Infections
Authors: Sobotka Harry , Friedlander Mae
Published: December 2022

The prozone phenomenon in serum treatment of experimental pneumococcus septicemia is described. The fact that excessive amounts of protective antibody in many instances fail to prevent death, is discussed. It is suggested that the presence of an interfering factor is responsible for the prozone. The mechanism of the action of this factor is treated mathematically for characteristic cases and the resulting formulae are applied to actual observations. This factor may interfere with the reaction between antibody and bacteria either by reacting with the antibody or by reacting with the antigen. The action of the antibody may be impaired to a certain extent by precipitation with the injurious factor which, under this assumption, is identical with the soluble specific substance as suggested by Felton and Bailey and by other authors. For instance if there are 100 units of antibody and 10 equivalent units of the interfering substance, then the potency of the antiserum will be reduced to that extent; the relative amount of this reduction will be constant however, in this example a reduction of 10 per cent; but this does not explain the complete inactivation of large doses of antibody as occurs in the prozone phenomenon. The interfering substance may react with the bacteria. In that case it does not decrease the neutralizing power of the antibody proper. Although it might be present only in minute quantities it reacts with the bacteria making some of them less susceptible or entirely resistant to the action of the antibodies. Thus both the limitation of protection to a certain maximal number of bacteria and the prozone can be explained on the same basis. The properties ascribed to the interfering factor sub 3 (b) and its irregular occurrence in antisera and concentrated antibody solutions suggest that it is a modified antibody.
Studies on the Antigenic Properties of the Ultraviruses
Authors: Schultz Edwin W.
Published: December 2022

In a recent critical review of the literature on the antigenic properties of the ultraviruses, the writer (1928) called attention to the fact that these agents of disease, as far as they have been studied, seem to exhibit antigenic properties which suggest placing them in the general group of toxins and ferments rather than with such antigens as bacteria and other more highly organized proteinaceous bodies. Since the various facts which have suggested such a probability have been fully treated in the paper referred to, it will be unnecessary to discuss them at length here. The writer will, therefore, confine himself in this paper to a more general outline of the theoretical and other considerations which have prompted the studies that are to appear under the general title indicated.

According to Zinsser (1915) anl~igens may be classified into two general classes.
Pasteurella Avicida Vaccination by the Oral, Subcutaneous, and Intravenous Methods
Authors: Barnes LaVerne
Published: December 2022

Subcutaneous vaccination is more effective than oral vaccination in stimulating the production of typhoid agglutinins in rabbits (1). It is questionable which method is more effective in stimulating the production of immunity. Besredka believes that agglutinins and other specific antibodies in the blood stream are practically negligible as factors in immunity (2). He believes that immunity is cellular and in order to produce a “solid” immunity, the vaccine must be applied directly to the body ceils. This immunity appears, in certain cases, within twenty-four hours. If Besredka is correct, current conceptions of immunity and methods of immunization will have to be modified.

Calmette (3), and Enlows (4) have reviewed the evidence concerning oral vaccination. Sufficient data regarding the comparative efficiency of oral, subcutaneous, and intravenous methods of vaccination in stimulating the production of immunity are not available.

The experiments described in this paper were designed to compare: (a) The production of agglutinins for Past. avicida in the blood of chickens and rabbits following oral, subcutaneous,and intravenous administrations of vaccine; and, (b) the resistante of the vaccinated animals to intravenous inoculations of Past. avicida.
Quantitative Studies on the Action of Compound Hemolysins
Authors: Gahl Rudolf
Published: December 2022

The experimental results on compound hemolysins obtained by Arrhenius and Manwaring were plotted by means of the system developed in the preceding paper. The resulting curves were studied and compared.

New experimental material designed to clear up the discrepancies will be presented in the next paper.