bluuebunny/crossref_metadata_2025 huggingface dataset:
Protective role of IgE in immunocompromised rat toxoplasmosis.
Authors: Ridel P R , Auriault C , Darcy F , Pierce R J , Leite P , Santoro F , Neyrinck J L , Kusnierz J P , Capron A
Published: December 2022

In contrast to euthymic adult Fischer rats, immunocompromised Nu/Nu animals develop a lethal infection when inoculated with the RH strain of the protozoan Toxoplasma gondii. However, a significant period of survival is obtained when Nu/Nu rats are passively transferred with sera from 28-day infected Fischer +/+ (euthymic) animals. Specific IgE are involved since IgE-depleted sera are unable to afford such a protection. Only excreted/secreted Ag or living tachyzoites are able to induce a significant protective IgE response in intact animals. In addition, platelets or, to a lesser extent, eosinophil-rich populations from Toxoplasma infected or excreted-secreted Ag-immunized euthymic animals bear surface IgE and are cytotoxic for the parasite in vitro. Also, adoptive transfer of immune platelets confers a significant degree of protection to Toxoplasma-infected Nu/Nu animals. Our results clearly show the key role of Ag present in both living parasites and excreted-secreted Ag to induce, in this model, a protective IgE response. In addition, as in other parasitic infections, platelets and probably eosinophils are the effector cells involved in controlling parasitic dissemination during Toxoplasma infection in immunocompromised rats.
Suppressive substance produced by T cells from mice chronically infected with Trypanosoma cruzi. III. Genetic restriction and further characterization.
Authors: Gao X M , Schmidt J A , Liew F Y
Published: December 2022

Earlier papers in this series reported that the culture supernatant of splenic L3T4+, Lyt-2- T cells from susceptible CBA mice chronically infected with Trypanosoma cruzi contain a SS3 that can inhibit the induction of delayed-type hypersensitivity to a wide range of Ag. The SS is a glycoprotein with an apparent molecular mass of 30 to 60 kDa and is distinct from T. cruzi Ag, IL-1, IL-2, IL-3 or IFN-gamma. It also has no effect on Th cells for antibody, cytotoxic T cells or immediate-type hypersensitivity. In this paper, we report that SS can suppress the induction of proliferating T cells but not the presentation of Ag to a cloned T cell line (D10). It also has no effect on the induction of delayed-type hypersensitivity in vitro. SS is produced by a number of inbred mouse strains irrespective of their susceptibility to infection with T. cruzi (BALB/c, highly susceptible; CBA, susceptible; C57BL/10, resistant) but only CBA mice are sensitive to the suppressive action of SS. This is so whether the SS is derived from CBA, BALB/c, or C57BL/10. The sensitivity to SS is not a feature of the H-2k haplotype inasmuch as B10.BR and BALB/k mice (also H-2k) do not respond to SS. Attempts to purify SS with a range of biochemical techniques substantially enriched the specific activity but failed to produce a substance visualizable by analytical gel electrophoresis. IEF chromatography revealed SS activity spanning a pH range from 6 to less than 4. This suggests that SS is likely to be a minor heterogeneous component of the suppressive supernatant. The genetically highly restricted nature of its action is intriguing and may explain some of the contradictory reports in the literature on this subject.
Adoptively transferred experimental autoimmune encephalomyelitis in SJL/J, PL/J, and (SJL/J x PL/J)F1 mice. Influence of I-A haplotype on encephalitogenic epitope of myelin basic protein.
Authors: McCarron R , McFarlin D E
Published: December 2022

Guinea pig basic protein (GPBP)-immune lymph node cells (LNC) from SJL, PL, and SJL x PL (F1) mice proliferated to whole GPBP and GPBP fragments 1-37, 43-88, and 89-169. All three strains of mice developed experimental allergic encephalomyelitis (EAE) by active immunization with whole GPBP or by passive transfer of LNC cultured with whole GPBP. SJL (H-2s) and PL (H-2u) mice developed EAE by active immunization with fragments 89-169 or 1-37, respectively, or by passive transfer of LNC cultured with the same Ag. F1 mice developed EAE by active immunization only with fragment 1-37 or by passive transfer of LNC cultured with either of the above fragments. Removal of macrophages (MO) from immune-F1 LNC resulted in the loss of a proliferative response and the ability to transfer EAE. Reconstitution of MO-depleted immune F1 T cells with either F1-, SJL-, or PL-MO restored the proliferative responses to whole GPBP and the three fragments. Cultures of immune F1 T cells reconstituted with any of the three MO populations and incubated with whole GPBP passively transferred EAE into naive F1 mice. Immune F1 T cells cultured with F1 MO in the presence of either fragment 1-37 or 89-169 transferred EAE. F1 T cells cultured with SJL MO were able to transfer EAE only if the Ag was fragment 89-169, whereas F1 T cells cultured with PL MO were able to transfer disease only if incubated in the presence of fragment 1-37. F1 mice are passively susceptible to EAE induced by adoptive transfer of cells reactive to either the N-terminal or C-terminal fragment and that the encephalitogenic determinant of GPBP is related to the genome of MO present in vitro.
Mitochondrial iron loss from leukemia cells injured by macrophages. A possible mechanism for electron transport chain defects.
Authors: Wharton M , Granger D L , Durack D T
Published: December 2022

Activated macrophages inhibit replication of murine lymphoblastic leukemia L1210 cells without lysis. This inhibition of replication is associated with abnormalities of mitochondrial electron transport at the level of NADH dehydrogenase (NADH-DH) and succinate dehydrogenase (SDH). The mechanism of inhibition is unknown, although it has been demonstrated that as NADH-DH and SDH activity is lost, iron is released from cells. Because both NADH-DH and SDH contain numerous iron-sulfur clusters, damage to these structures may be one result of injury by activated macrophages. L1210 cells were labeled with 55Fe and co-cultivated with activated murine peritoneal macrophages (injured L1210 cells). At 48 h, injured L1210 cells had released 83 +/- 8% (mean +/- SEM of 55Fe activity into the media, compared with 25 +/- 4% release from control and 37 +/- 7% from nondividing mitomycin C-treated control cells. All cells were greater than 90% viable. These differences were also reflected in the iron content of the cells. Mitochondria were then separated by centrifugation after cell disruption and 55Fe activity was found to be similarly decreased in both mitochondrial and nonmitochondrial fractions of injured L1210 cells. To further characterize the changes in mitochondrial iron content, mitochondrial proteins from injured and control L1210 cells were separated by IEF and 55Fe activity of gel slices was determined. There was selective loss of 55Fe activity in the area of the gel corresponding to SDH and NADH-DH, suggesting that iron loss from iron-sulfur clusters may occur in L1210 cells injured by activated macrophages. Iron uptake into L1210 cells after removal from macrophages showed a rapid large influx of radioactive iron. L1210 cells in contact with macrophages appear to develop an iron-depleted state, which is dependent on the continued presence of macrophages.
Idiotype vaccines against human T cell leukemia. II. Generation and characterization of a monoclonal idiotype cascade (Ab1, Ab2, and Ab3).
Authors: Bhattacharya-Chatterjee M , Chatterjee S K , Vasile S , Seon B K , Kohler H
Published: December 2022

Previously, we had generated anti-Id mAb (Ab2) binding to a hybridoma SN2 (Ab1), which recognizes a glycoprotein, gp37, expressed by human leukemic T cells. To characterize these anti-idiotopes further, they were used to immunize mice and rabbits. Several murine anti-anti-Idiotype mAb (Ab3), mostly of IgM-k isotype, were obtained. mAb3 and sera from rabbits immunized with Ab2 contained antibodies that bind to gp37 Ag and leukemic MOLT-4 and JM cells. Also, mAb3 and immune sera from rabbits competed with Ab1 for binding to MOLT-4 cells. They inhibited the binding of iodinated Ab1 to Ab2 indicating that Ab3 in mice and rabbits shares idiotopes with Ab1 (SN2). Furthermore, both the murine mAb3 and rabbit polyclonal Ab3 immunoprecipitated the same gp37 Ag as SN2 (Ab1). The production of Ag-specific Ab3 (Ab1') in mice and rabbits in absence of any exposure to gp37 indicates that these Ab2 may indeed carry the internal image of the gp37 Ag. Such anti-idiotopes (Ab2 beta) may be useful as Ag substitute for the induction of therapeutic immunity in T cell leukemia patients.
IL-1 as a co-factor for lymphokine-secreting CD8+ murine T cells.
Authors: Mizuochi T , McKean D J , Singer A
Published: December 2022

Immunologically important among the known biologic activities of IL-1 is its ability to function as a co-factor for responses mediated by lymphokine secreting CD4+ Th cells. In contrast to its known effects in CD4+ T cell responses, IL-1 is not known to play a role in CD8+ T cell responses. In the present study, we have assessed the ability of murine recombinant IL-1 to function as a co-factor for stimulating CD8+ T cells to secrete lymphokines such as IL-2. We found that, in conjunction with either Ag or mitogen, IL-1 is able to stimulate lymphokine-secreting CD8+ T cells. Furthermore, we found that, as a consequence of its stimulation of lymphokine-secreting CD8+ T cells, IL-1 is able to reconstitute MHC class I allospecific cytolytic T lymphocyte responses by cell populations depleted of both accessory cells and CD4+ T cells. These results demonstrate that the biologic activity of IL-1 is not restricted to CD4+ cell responses, and suggests that IL-1 can function as a co-factor for the stimulation of lymphokine-secreting Th cells regardless of their CD4/CD8 phenotype. If IL1 acts directly on lymphokine-secreting T cells or on the APC with which they interact is not yet certain.
DNA rearrangements affecting both variable and constant regions of Ig H chain genes in MPC11 mouse myeloma variants.
Authors: Gilmore G L , Bard J A , Birshtein B K
Published: December 2022

We have examined the mechanisms that account for short Ig H chain production in two variants of the mouse myeloma cell line MPC11 (IgG2b, kappa) by mRNA sequencing and restriction enzyme mapping. One variant, F5.5, has a thymidine residue inserted into the (CH3) domain, of the Ig H chain, resulting in premature termination and translation of a gamma 2b H chain of 50,000 m.w. A second variant, E5.7A12, contains gamma 2a-derived sequences that extend from near the 3' end of the CH2 domain to the intervening sequence between the CH2 and CH3 domains, consistent with a microrecombination event (defined as either a double cross-over or gene conversion event). In this variant, the 5' end of the CH3 domain has been deleted, but the remainder of the gamma 2b(CH3) domain is present, resulting in the translation of a gamma 2b-gamma 2a-gamma 2b H chain of 52,000 m.w. Additional rearrangements affecting sequences in or adjacent to the variable region accompany H chain constant region alterations in these cell lines and subclones of these cell lines. In F5.5, novel sequences have recombined within one of two duplicated copies of the VH gene. In a sister clone of E5.7A12 that has ceased H chain production (E5.7A14), new sequences have recombined within 300 bp 5' of the enhancer element. Both F5.5 and E5.7A12, like their immediate unstable precursor cells, fail to assemble H-H dimers, halting the Ig assembly process at the heavy-light stage, and do not secrete H chains. We speculate that defects in H chain assembly and secretion, as exemplified by the parents of these variants (i.e., intermediates of these secondary variants), reactivate the Ig gene rearrangement machinery and result in the formation of these putatively equally unstable secondary variants.
Analysis of T hybridomas prepared from a T cell clone with three specificities. Recognition of self + X and allo-H-2 determinants segregates from recognition of Mlsa determinants.
Authors: Webb S R , Okamoto A , Sprent J
Published: December 2022

To see k information on T cell recognition of Mlsa determinants, hybridomas were prepared from a well-characterized F23.2+ (V beta 8.2+) T cell clone specific for three different ligands, i.e., 1) Mlsa determinants, 2) fowl gamma-globulin (F gamma G) plus self-H-2 (H-2d), and 3) allo-H-2, e.g., H-2p, determinants. Fusion of the clone to the BW5147 thymoma line produced a triple-reactive T hybridoma which generated two types of spontaneous variants. One type of variant (type I) lost Mlsa reactivity but retained reactivity to both F gamma G/H-2d and allo-H-2p. These variants, which were generated at high frequency, stained strongly with a mAb, A1.57, with idiotypic specificity for the TCR molecules of the parental clone. The second type of variant (type II) reacted to Mlsa determinants but showed no reactivity to F gamma G/H-2d or to allo-H-2p. These variants failed to express the A1.57 idiotypic determinants of the parent clone, but were F23.2+ (V beta 8.2+); nonequilibrium pH gradient electrophoresis analysis suggested that these hybrids expressed a mixed TCR heterodimer composed of the parental clone beta-chain and the BW5147 alpha-chain. Three aspects of the data are very difficult to accommodate with the view that Mlsa, F gamma G, and allo-H-2 determinants are all recognized via a common TCR molecule: 1) the independent (and frequent) segregation of Mlsa reactivity from F gamma G/H-2d and allo-H-2p reactivity, 2) the retention of Mlsa reactivity by the type II variants despite loss of the parental clone alpha-chain, and 3) the loss of Mlsa reactivity by the type I variants despite high expression of the A1.57+ TcR molecules derived from the parental clone. The data support a model in which Mlsa determinants are recognized by a separate T cell structure, which we envisage as a monomorphic accessory molecule unrelated to the TCR. Since the type II hybridoma variants invariably retained quantitatively normal TcR expression, the triggering phase of anti-Mlsa responses appears to be TCR dependent. The model we favor is that anti-Mlsa/Mlsa interaction increases TCR binding with Ia epitopes to above the threshold required for cell triggering. A key feature of this model is that Mlsa and Ia determinants are recognized as separate structures rather than as a complex.
Idiotypic vaccination as a treatment for a B cell lymphoma.
Authors: George A J , Folkard S G , Hamblin T J , Stevenson F K
Published: December 2022

To develop a model for the active immunotherapy of human B cell malignancy we vaccinated tumor-bearing animals with a well defined tumor associated Ag, the idiotypic Ig. The tumor used was the mouse B cell lymphoma BCL1, a highly malignant tumor in which transfer of a single tumor cell to a syngeneic mouse is capable of causing disease and eventual death. Varying doses (10(2) to 10(4] of BCL1 cells were given to mice on day 0 of the experiment, and treatment by active immunization was initiated on day 3. Immunization with purified, tumor-derived, idiotypic IgM (BCL1 IgM) coupled to keyhole limpet hemacyanin (KLH) was highly effective in treating mice challenged with 10(2) or 10(3) BCL1 cells, but less effective in mice that had received 10(4) tumor cells. Immunization with unconjugated BCL1 IgM showed no signficant therapeutic benefit. Coupling of the IgM to KLH led to higher levels of anti-idiotypic antibody after immunization; however, the higher levels were probably not responsible for the control of the malignancy as there was no correlation in healthy immunized animals between the levels of anti-idiotypic antibody, measured immediately before tumor challenge, and survival. This lack of correlation is due to the emergence of variant tumors in such protected mice. A more significant factor in the therapeutic advantage of KLH conjugation could be that immunization with BCL1 IgM-KLH led to an earlier induction of the anti-idiotypic response than immunization with BCL1 IgM and, as the BCL1, lymphoma divides rapidly, the speed of induction of the immune response may be important in outstripping tumor cell growth. Mice with BCL1 tumour showed some evidence of immunosuppression as indicated by a reduced ability to mount an immune response against KLH. Although it is not possible to model spontaneous human lymphoma accurately, the generation of a functional anti-idiotypic response capable o eliminating a malignant animal lymphoma in situ opens up the possibility of a limited trial of active immunotherapy in selected human patients.
Release of tumor necrosis factor-alpha from macrophages. Enhancement and suppression are dose-dependently regulated by prostaglandin E2 and cyclic nucleotides.
Authors: Renz H , Gong J H , Schmidt A , Nain M , Gemsa D
Published: December 2022

PGE2 has previously been shown to suppress various leukocyte functions. In this study, we examined whether PGE2 would affect release of TNF-alpha from rat resident peritoneal macrophages. Two different, dose-dependent effects were observed: low PGE2 concentrations (0.1 to 10 ng/ml) stimulated, whereas higher concentrations (greater than 10 ng/ml) suppressed TNF-alpha release. PGE2-stimulated TNF-alpha production was dependent on de novo protein synthesis and was associated with an intracellular rise of cGMP. The importance of cGMP as an intracellular messenger for PGE2 was confirmed by the following evidence: (1) low PGE2 concentrations preferentially increased cGMP and not cAMP and (2) cGMP, either exogenously added or endogenously generated by sodium nitroprusside, were efficient stimulators of TNF-alpha production. In contrast, agents increasing intracellular cAMP concentrations such as PGE1, higher PGE2 doses, isoproterenol, and theophylline, all suppressed TNF-alpha synthesis. Only resident, but not casein-elicited or Corynebacterium parvum-activated macrophages, were stimulated by low PGE2 concentrations to increase TNF-alpha production. In tumor cytotoxicity assays, PGE2-activated macrophages were active only against TNF-alpha-sensitive target cells. These findings demonstrate that TNF-alpha synthesis in macrophages is up-regulated by cGMP and down-regulated by cAMP, which indicates that cyclic nucleotides act as intracellular messengers for extracellular signals of macrophage activation.
Generation and functional characterization of T cell lines and clones specific for Schistosoma japonicum egg antigen in humans.
Authors: Ohta N , Edahiro T , Tohgi N , Ishii A , Minai M , Hosaka Y
Published: December 2022

T cell lines specific for Schistosoma japonicum egg Ag were established in vitro from patients with chronic schistosomiasis japonica, and investigated their possible immunopathologic roles by testing lymphokines production and in vitro granuloma formation assay. All lines tested had surface phenotypes of CD3+ CD4+ CD8-, and showed S. japonicum soluble egg Ag (SEA)-specific proliferation requiring HLA-DR-restricted Ag presentation. Of these fractions of SEA separated by gel filtration, Fraction II (m.w. 7,000 to 18,000) and III (m.w. 7,000) induced strong proliferation of T cell lines, whereas fraction I (m.w. 18,000+) failed to induce detectable proliferation to any T cell lines tested. One of the T cell lines was cloned by micromanipulation: two of eight clones responded only to fraction II, and six to both fractions II and III. We observed that four of eight clones tested produced IL-2 in response to SEA, and three of them were able to transfer S. japonicum egg-specific granulomatous hypersensitivity in vitro to an HLA haplo-identical individual without previous schistosome infection. These immunopathologic functions of T cell clones seemed to be activated by at least two distinct epitopes of SEA. Our present observations suggest that at least two distinct CD4+ human T cells, both of which recognize epitopes expressed on SEA molecules of less than 18 kDa, might have critical roles in granulomatous hypersensitivity to eggs of S. japonicum in humans.
A monoclonal antibody reacting with distinct adhesion molecules defines a transition in the functional state of the receptor CD11b/CD18 (Mac-1).
Authors: Altieri D C , Edgington T S
Published: December 2022

CD11b/CD18 (Mac-1) is a member of the leukocyte integrin family, a group of receptors that have been implicated in various effector functions and cellular collaboration in the immune response. It has been shown previously that CD11b/CD18 on cells of monocyte and myeloid lineage appears to undergo rapid activation and acquire new functional receptor specificities after exposure to selected agonists such as adenosine diphosphate (ADP). We now show that ADP induces a reconformation of the CD11b/CD18 receptor with exposure of new epitopes characteristics of this activated state. By direct binding studies, flow cytometry, and immunoprecipitation experiments, it has been found that the mAb 7E3 reacts with CD11b/CD18 only after ADP-stimulation of the cell suspension. The activated state of CD11b/CD18 induced by ADP and recognized by 7E3 can also be recapitulated by agonists inducing transients in cytosolic Ca2+ such as the chemoattractant FMLP. Moreover, this process of receptor activation does not involve quantitative mobilization of the subcellular storage pool of CD11b/CD18 to the plasma membrane. Because 7E3 also recognizes a qualitative, ADP-mediated activated state of the platelet adhesion receptor GP IIb/IIIa, it is suggested that transients in cytosolic Ca2+ might represent early secondary events for a general pathway of rapid activation of integrin receptors and, as such, represent important signals for cellular interactions in the immune response.
Fine mapping of an H-2Kk restricted cytotoxic T lymphocyte epitope in SV40 T antigen by using in-frame deletion mutants and a synthetic peptide.
Authors: Rawle F C , O'Connell K A , Geib R W , Roberts B , Gooding L R
Published: December 2022

The CTL response to SV40 in C3H/HeJ mice is directed against the tumor (T) Ag and is H-2Kk restricted. CTL specific for both the amino terminus (residues 1-271) and the carboxyl terminus (residues 512-708) of the T Ag molecule have been detected, and we have previously cloned CTL of both specificities. In this paper we show that the panel of 10 CTL clones specific for the C-terminal region includes clones specific for three different epitopes, termed C1, C2, and C3. Epitopes C1 and C2 are conserved in the T Ag of the related papova viruses BK and SA12, and only epitopes C2 and C3 are present on SV40 transformed targets bearing the Kk mutant Kkml. Epitopes C1 and C2 were mapped to residues 563-576 by using in-frame deletion mutants of SV40 T antigen, and all clones specific for these two epitopes can lyse Kk bearing target cells in the presence of a synthetic peptide comprising residues 559-576. Kk and Kkml differ at residue 152, which is located in the Ag-binding pocket. Because epitopes C1 and C2 can be formed by the same antigenic peptide, but epitope C1 is not present on SV40 transformed Kkml cells, epitopes C1 and C2 must differ in the contribution made by residue 152 of the MHC class I molecule. These data show that CTL epitopes on transformed cells can be made up of Ag fragments, and strengthen the idea that this is a general phenomenon for both class I and class II restricted T cell epitopes.
Ig lambda-producing B cells do not show feedback inhibition of gene rearrangement.
Authors: Gollahon K A , Hagman J , Brinster R L , Storb U
Published: December 2022

In order to study the regulation of expression of Ig lambda genes we have analyzed lambda-producing hybridomas derived from transgenic mice which harbor a functionally rearranged kappa transgene. We also analyzed lambda-producing hybridomas from nontransgenic mice. Surprisingly, all but one of the transgenic lambda-hybridomas co-produce kappa L chains. Also, in contrast to transgenic kappa-hybridomas, most lambda-hybridomas have rearranged endogenous kappa genes despite the presence of transgenic kappa-chains and endogenous H chains. Analysis of spleen cells and hybridomas from nontransgenic mice shows that about 20% of lambda-producing B cells in the spleen co-produce kappa, and a similar proportion of lambda-hybridomas from normal spleens produce both kappa- and lambda-chains. The data argue strongly against the strictly sequential expression of kappa and lambda genes. We present a new model for the regulation of kappa and lambda gene expression, whose key feature is the distinction between a kappa cell lineage in which Ig gene rearrangement is susceptible to feedback by a complete antibody molecule at the pre-B cell stage, and a kappa lambda B cell lineage which does not show feedback inhibition during B cell development.
Comparison of the cytotoxic potency of T101 Fab, F(ab')2 and whole IgG immunotoxins.
Authors: Derocq J M , Casellas P , Laurent G , Ravel S , Vidal H , Jansen F
Published: December 2022

The in vitro killing of the human CEM cell line was studied by using ricin A-chain immunotoxins constructed with either the whole IgG or the Fab and F(ab')2 fragments of the same T101 (anti-CD5) antibody. In the presence of ammonium chloride as an activator, the "whole" immunotoxin as well as the "fragment" immunotoxins did not show any significant difference in the cell killing efficacy. In contrast, without the activator, the efficacy of the T101 immunotoxin was greatly improved when fragments were used. Indeed, at a saturating dose, a cytoreduction of three orders of magnitude was obtained with the fragment immunotoxins vs less than one order of magnitude for the whole immunotoxin, as assessed in a clonogenic assay. This enhancing effect was related to better cell killing kinetics, because with a similar amount of A-chain molecules bound per cell, T101 fragment immunotoxins achieved a twofold faster protein synthesis inactivation rate than the corresponding whole IgG immunotoxin. No significant difference in activity was shown between monovalent (Fab) and divalent (F(ab')2) forms of fragment immunotoxins. The observation that T101 fragment immunotoxins were more potent than intact immunotoxins was extended to another fragment immunotoxin constructed with an antibody (F111.98) directed against a different epitope of the CD5 Ag. In another model (anti-CD22 1G11 antibody on Raji cells), the fragment immunotoxin did not show any superiority over the IgG immunotoxin which was by itself very potent, strongly suggesting an Ag-dependent phenomenon.
Protein kinase C modulates actin conformation in human T lymphocytes.
Authors: Phatak P D , Packman C H , Lichtman M A
Published: December 2022

We studied the effect of activators and inhibitors of protein kinase C on actin conformation in human blood lymphocytes by flow cytometry and gel electrophoresis. PMA, 1-oleyl-2-acetyl-glycerol, and mezerein, activators of protein kinase C, caused an increase in lymphocyte F-actin within 2 to 5 min. After stimulation with PMA, lymphocytes formed pseudopods containing an increased concentration of F-actin and had an increase of actin in the Triton-insoluble cytoskeletal fraction. Sphingosine and H-7, inhibitors of protein kinase C activation, inhibited the increase in F-actin induced by PMA. The increase in F-actin in response to PMA was striking in Th and Ts lymphocytes (2- to 3-fold increase), but B lymphocytes had only a slight increase (1.15-fold). Thus, activation of protein kinase C modulates actin conformation specifically in T lymphocytes.
Complete nucleotide sequence of the chromosomal gene for human IL-4 and its expression.
Authors: Arai N , Nomura D , Villaret D , DeWaal Malefijt R , Seiki M , Yoshida M , Minoshima S , Fukuyama R , Maekawa M , Kudoh J
Published: December 2022

We have isolated a chromosomal DNA segment of the human IL-4 gene based on homology with a human IL-4 cDNA sequence and determined its complete nucleotide sequence. The human IL-4 gene, which occurs as a single copy in the haploid genome, is mapped on chromosome 5. It is composed of four exons and three introns and is approximately 10 kilobase pairs in size. 5'-Flanking regions of human and mouse IL-4 genes share about 85% homology extending more than 500 base pairs upstream of a "TATA" like sequence. Several patches of sequences are found in the 5'-flanking region of the human IL-4 gene which are homologous to sequence in the 5'-flanking regions of the IL-2, IL-3, IL-5, and granulocyte-macrophage (GM)-CSF genes. The IL-4 gene is inducible after treatment of human T cell clone by phorbol-12-myristate-13-acetate (TPA) and calcium ionophore A23187. The 2.3-kb 5'-flanking region of the human IL-4 gene transiently transfected into Jurkat human T cell leukemia cells is activated efficiently in response to TPA and A23187 stimulation and, although less efficiently, by human T cell leukemia virus type I-encoded p40x or BPV-encoded E2 protein. Combination of TPA/A23187 and p40x or E2 protein further augmented the level of expression.
An in situ study of B-lymphocytopoiesis in rat bone marrow. Topographical arrangement of terminal deoxynucleotidyl transferase-positive cells and pre-B cells.
Authors: Hermans M H , Hartsuiker H , Opstelten D
Published: December 2022

To understand bone marrow (BM) as a site of B-lymphocytopoiesis, insight into the topographical arrangement of developing B cells and their relationships to the microenvironment in vivo is required. To study the spatial distribution of B lymphocyte progenitors defined by intracellular markers (cytoplasmic mu H chain and nuclear terminal deoxynucleotidyl transferase (TdT], we developed a technique to cut frozen femurs of rat, yielding cross-sections with intact subendosteal and central marrow. By using (double) immunofluorescence staining techniques we located pre-B and TdT+ cells, and IgM+ B cells in those sections. Of the B cells present in BM, one-third was accumulated in the lumen of blood sinuses. The rest were in the BM parenchyma, as were virtually all pre-B and TdT+ cells. The subendosteal area was twice as rich in pre-B and TdT+ cells as the central area, and within the subendosteal area a profound positive gradient toward the bone was evident. B cells showed an equal distribution over the center and the periphery of the BM. The distribution patterns of B lineage cells in the BM parenchyma were analyzed and shown in part to deviate from random distribution. Additional study of clonal development and microenvironmental factors in hematopoiesis will have to clarify the underlying mechanisms for the observed distribution patterns of B cell precursors in BM.
T cell induction of macrophage IL-1 during antigen presentation. Characterization of a lymphokine mediator and comparison of TH1 and TH2 subsets.
Authors: Weaver C T , Duncan L M , Unanue E R
Published: December 2022

We described in a previous study two pathways by which Th cells induced macrophage membrane IL-1(mIL-1) during Ag presentation. One pathway was lymphokine-independent and mediated by cell-cell contact. The second was lymphokine-dependent. We have now characterized this lymphokine and show that it belongs to the TNF family of proteins. All TH1 and most TH2 clones produced the lymphokine, although TH1 levels were markedly greater. Both types of clones also induced macrophage mIL-1 by cell-cell contact (i.e., in the absence of lymphokine release). Examination of macrophages by in situ hybridization showed that both IL-1 alpha and IL-1 beta mRNA were coordinately induced during Ag presentation to either TH1 or TH2 clones.
Reactivity of anti-human milk fat globule antibodies with synthetic peptides.
Authors: Xing P X , Tjandra J J , Reynolds K , McLaughlin P J , Purcell D F , McKenzie I F
Published: December 2022

The nucleotide sequence of partial cDNA clones coding for the core protein of a human polymorphic epithelial mucin has recently been obtained, this mucin consists of a highly conserved 60 bp tandem repeat and the amino acids commonly found are PDTRPAPGSTAPPAHGVTSA. We synthesized three peptides, 1) P1.24 containing the 20 amino acids and four amino acids (PDTR) of the adjoining repeat; 2) P1.15 consisting of the first fifteen (PDTRPAPGSTAPPAH) and P1.09 the second nine amino acids (GVTSAPDTR) of peptide P1.24. The reactivities of the synthetic peptides with mAb known to react with breast cancer (BC1, BC2, BC3, HMFG-1, 3E1.2, and RCC-1) were studied. The synthetic peptide, P1.24, corresponding to the antigenic sequence predicted from the tandem repeat reacted with antibodies BC1, BC2, and BC3 (known to react with human milk mucin and mucin expressed in breast cancer) and the antibody HMFG-1 which was used to select the cDNA clones. In addition, the epitopes recognized by BC1, BC2, and BC3 appear to be in the same region of the molecule represented by their reactions with the nine amino acids in peptide P1.09 (GVTSAPDTR). By contrast, other antibodies such as 3E1.2 which reacts only weakly with components of human milk, and RCC-1 that detects a low Mr component (95 kDa) in breast cancer, had no specific reaction with the synthetic peptides, indicating that their epitopes are distinct from those of BC1, BC2, BC3, and HMFG-1. Inasmuch as the antibodies HMFG-1, BC1, BC2, and BC3 react with the fully processed milk mucin, it is likely that some of the peptide is exposed, even in the fully glycosylated molecule. Identification of the different epitopes could lead to the development of "second generation" mAb with enhanced specificity for breast carcinoma using the appropriate synthetic peptides as immunogens.
HIV-1 and its envelope glycoprotein down-regulate chemotactic ligand receptors and chemotactic function of peripheral blood monocytes.
Authors: Wahl S M , Allen J B , Gartner S , Orenstein J M , Popovic M , Chenoweth D E , Arthur L O , Farrar W L , Wahl L M
Published: December 2022

Peripheral blood monocytes from AIDS patients exhibit defective migratory responses to chemotactic stimuli in vitro and to inflammatory sites in vivo. In studies presented here, normal monocytes were infected with the HIV-1/HTLV-IIIBa-L isolate in vitro and evaluated for chemotactic responsiveness. Within 2 days after viral exposure, but before evidence of virus production in the monocytes, chemotactic activity was significantly impaired. Decreased chemotactic activity was associated with modulation of receptors for the chemotactic ligands, C5a and FMLP, on the monocyte cell surface. In addition to HIV-1, monocytes treated with purified HIV-1 envelope glycoprotein gp120 demonstrated a comparable modulation of chemotactic ligand receptors and migratory function. In addition, the HIV-1 or HIV-1 gp120-treated monocytes were induced to undergo differentiation as monitored by HLA-DR expression. Immunoprecipitation of the gp120 with a specific antibody reversed its effects on monocyte chemotaxis and HLA-DR expression. Taken together, these data indicate that the initial interaction of HIV-1 with the monocyte is not passive, but that the binding of HIV-1 and/or HIV-1 gp120 to the CD4R on monocytes transduces a signal leading to transient monocyte activation.
Effects of neonatal injections of anti-CD3 epsilon monoclonal antibodies on the T cell functions of adult mice.
Authors: Rueff-Juy D , Drapier A M , Cazenave P A
Published: December 2022

The effect of neonatal injections of anti-CD3 mAb on the subsequent immune responsiveness of adult mice has been investigated. The data indicate that neonatal treatment with three injections of 50 microliters of anti-CD3 epsilon ascitic fluid induce a profound depletion of T cells in the peripheral lymphoid organs but do not modify the absolute number of thymocytes. This treatment completely abolishes the T cell functions of mice at least 3 wk after the last injection of mAb. In the thymus, this suppression is associated with a decrease in the number of TcR/CD3 molecules in the dull CD3+ cells and with a drastic reduction the bright CD3+ population. However, the amount and the size of the TcR alpha,beta and CD3 epsilon mRNA transcripts are not modified, suggesting that the down-regulation of the TcR/CD3 complex induced by anti-CD3 mAb does not exert a feedback inhibition on the transcription of TcR genes. The suppression induced by neonatal injections of anti-CD3 epsilon mAb is reversible and the induction of immune responses requires the reappearance of a minimal number of bright CD3+ cells. However, this suppression can be maintained without side effects for several months provided that anti-CD3 mAb were administered at 7-day intervals from birth. This injection schedule should allow the study of the effect of anti-CD3 antibodies during the T cell ontogeny on the establishment of the B and T cell repertoires.
Class II restriction in mice to the malaria candidate vaccine ring infected erythrocyte surface antigen (RESA) as synthetic peptides or as expressed in recombinant vaccinia.
Authors: Lew A M , Langford C J , Pye D , Edwards S , Corcoran L , Anders R F
Published: December 2022

The immune response to three peptides corresponding to the repeat regions of the malaria candidate vaccine ring infected E surface Ag (RESA) were studied. Both antibody responses and lymphocyte stimulation in mice injected with these peptides without carrier were found to be restricted to certain MHC class II haplotypes. Mice bearing IAk were strong responders to all three peptides. Mice bearing IAd were strong responders only to the 3' repeat peptides, the octamer and tetramer. Mice bearing Is or Iq did not respond to any repeat peptides. Remarkably, the pattern of genetic restriction of the antibody response to the entire RESA as expressed in vaccinia indicated that there were no other epitopes besides the three repeats. Because only one class II haplotype (i.e., k) out of five tested responded strongly to this peptide and only two out of five (i.e., k and d) responded to the octamer or tetramer, it may be difficult to achieve a good immune response against RESA in most or all humans.
Increment in the Ta1+ cells in the peripheral blood and thyroid tissue of patients with Graves' disease.
Authors: Eguchi K , Ueki Y , Shimomura C , Otsubo T , Nakao H , Migita K , Kawakami A , Matsunaga M , Tezuka H , Ishikawa N
Published: December 2022

The present study utilized the anti-Ta1 mAb to characterize the cell surface phenotypes of peripheral blood and intrathyroidal lymphocytes in patients with Graves' disease. We found an increase in PBL bearing the Ta1 Ag in untreated patients. The euthyroid patients in remission, induced by antithyroidal drugs, radioisotope therapy, and subtotal thyroidectomy, had lower percentages of Ta1+ cells than did untreated patients. An increased percentage of Ta1+ cells in untreated patients was found in both CD4+ cells and CD8+ cells. The ratio of CD4+Ta1+ cells to CD8+Ta1+ cells in untreated patients was significantly higher than that of normal subjects. There was a positive correlation between the percentage of Ta1+ cells and the level of anti-TSH receptor antibody. In this prospective study, the proportion of Ta1+ cells was decreased in parallel with the reduction in anti-TSH receptor antibody and free T3 levels. In the chronically treated patients, the proportion of Ta1+ cells in the thyroid tissue was, yet similar to that in the peripheral blood, markedly increased in comparison to that of normal subjects. In contrast to Ta1+ cells, the thyroid tissue had a significantly higher percentage of HLA-DR+ T cells than did the paired peripheral blood. The proliferative responses of the Ta1+ cell-enriched population isolated from untreated patients toward thyroglobulin and microsomal Ag were markedly higher than those in a Ta1+ cell-depleted population, but both populations were able to respond equally to PHA. These results suggest that the Ta1+ cells may include Ag-triggered memory cells that are reactive with thyroid-specific Ag. Furthermore, monitoring such cells may provide an objective measure of abnormal immunologic activity.
Influence of IL-1 alpha and -1 beta on the survival of human bone marrow cells responding to hematopoietic colony-stimulating factors.
Authors: Hangoc G , Williams D E , Falkenburg J H , Broxmeyer H E
Published: December 2022

Purified recombinant human (rhu) IL-1 alpha and IL-1 beta were evaluated for their effects on the proliferation and survival of granulocyte-macrophage (CFU-GM) and erythroid (BFU-E) progenitor cells from normal human bone marrow (BM). Using nonadherent low density T lymphocyte depleted (NALT-) BM cells cultured in the presence or absence of IL-1, CSF-deprivation studies demonstrated that IL-1 alpha or IL-1 beta by itself did not enhance the proliferation of CFU-GM or BFU-E. They did, however, promote the survival of progenitors responding to the delayed addition of media conditioned by the 5637 cell line (5637 conditioned medium), rhu GM-CSF and erythropoietin. The survival promoting effects of IL-1 alpha on CFU-GM and BFU-E were neutralized by anti-IL-1 alpha mAb added to the cultures. The survival promoting effect of IL-1 alpha did not appear to be mediated by CSF, because neither CSF nor erythroid burst promoting activity were detectable in cultures in which NALT- cells were incubated with rhuIL-1 alpha. In addition, suboptimal concentrations of rhu macrophage CSF (CSF-1), G-CSF, GM-CSF, and IL-3, which were just below the levels that would stimulate colony formation, did not enhance progenitor cell survival. Survival of CFU-GM and BFU-E in low density (LD) bone marrow cells did not decrease as drastically as that in NALT- BM cells, and exogenously added IL-1 did not enhance progenitor cell survival of CFU-GM and BFU-E in LD BM cells. However, addition of anti-IL-1 beta decreased survival of CFU-GM and BFU-E in LD BM cells. These results implicate IL-1 in the prolonged survival of human CFU-GM and BFU-E.
Interspersion of the VHQ52 and VH7183 gene families in the NFS/N mouse.
Authors: Kleinfield R W , Weigert M G
Published: December 2022

Deletion mapping analysis has shown that members of the VH7183 and VHQ52 gene families are interspersed in the NFS/N mouse. To obtain direct evidence that members of these gene families are physically linked, an NFS/N liver library was constructed and genomic clones were analyzed for hybridization to both VHQ52 and VH7183 gene probes. Four clones were identified which contained both VHQ52 and VH7183 hybridizable restriction fragments. Two clones containing rearranged VHQ52 genes were also found to hybridize with the VH7183 gene probe. Sequence analysis of three of the VH7183-containing restriction fragments indicate that all are pseudogenes which contain interruptions at either the 5' and/or 3' ends of the VH coding region. Given the D-proximal location of at least a portion of the VHQ52 gene family relative to VH7183 in NFS/N mice, and the known correlation between D proximity and the frequency of VH gene utilization, 22 NFS/N-derived pre-B cell lines were analyzed for VHQ52 gene utilization. More than 40% of the identified H chain (VHDJH) rearrangements in this survey used members of this gene family. Furthermore, analysis of poly(A)+ RNA from NFS/N fetal liver and adult spleen also indicates preferential utilization of VHQ52 family in fetal liver. Kinetic studies show, however, that there are no changes in relative utilization throughout fetal ontogeny. The implications of these findings for the expression and randomization of the VH repertoire are discussed.
Late events in B cell activation. Expression of membrane alkaline phosphatase activity.
Authors: Burg D L , Feldbush T L
Published: December 2022

Alkaline phosphatase (APase) has been previously described as a membrane marker correlating with B cell proliferation after stimulation by selected B cell mitogens. We have found, however, that the appearance of B cell membrane APase correlates more closely with differentiation than with proliferation. This conclusion has been drawn from the following observations: 1) APase activity appears well after peak B cell thymidine uptake, 2) mitogens which stimulate only B cell proliferation (Salmonella typhimurium mitogen) fail to induce expression of the enzyme, and 3) when proliferation of mitogen-activated B cells is inhibited, APase activity is not suppressed and may even be augmented. In addition to membrane expression, APase is also spontaneously shed into the surrounding milieu, perhaps as a result of endogenous phospholipase activity. By using a group of well-characterized inhibitors, the APase activity was shown to belong to class I (similar to the bone/liver/kidney class). Because APase always appears in differentiating but not proliferating cells, we would propose that the enzyme appearance is a late marker of B cell activation, associated with cell progression to differentiation and consequent IgM synthesis.
Delineation of several DR-restricted tetanus toxin T cell epitopes.
Authors: Demotz S , Lanzavecchia A , Eisel U , Niemann H , Widmann C , Corradin G
Published: December 2022

We have characterized five human T cell clones specific for tetanus toxin. The combination of different techniques allowed us to precisely map two T cell epitopes within fragments 830-843 and 1273-1284 of tetanus toxin, as formally demonstrated by the use of corresponding synthetic peptides. The three other T cell clones were specific for regions 2-602, 604-742, and 865-1315 of tetanus toxin, respectively. The five T cell clones were shown to be restricted to HLA-DR Ag. Furthermore, the allele of HLA-DR utilized by the various epitopes has been determined. The use of HLA-DR-transfected L cells as APC directly demonstrated that two epitopes, one of which represented by fragment 1273-1284, were recognized in association with HLA-DRw52a. For the other three T cell epitopes, the data strongly suggested they were recognized in association with HLA-DR5. Finally, a sixth T cell clone was shown to be specific for tetanus toxoid, the vaccinal preparation of tetanus toxin, and not for other tetanus toxin fragments. This indicated that immunization with tetanus toxoid probably elicits a T cell response directed only in part against native tetanus toxin.
T help requirements for the generation of an in vivo IgE response: a late acting form of T cell help other than IL-4 is required for IgE but not for IgG1 production.
Authors: Finkelman F D , Holmes J , Urban J F , Paul W E , Katona I M
Published: December 2022

To further define requirements for T cell help in the stimulation of an in vivo IgE response, we studied a system in which the injection of mice with a goat antibody to mouse IgD (GaMD) stimulates large polyclonal IgG1 and IgE responses. In this system, both responses are blocked by anti-CD4 antibody, but only the IgE response is blocked by (anti-IL-4) antibody. Anti-CD4 antibody, if injected 5 days after GaMD, was found to inhibit the GaMD-induced IgE response to a much greater extent than the IgG1 response, even though both responses occur simultaneously and are inhibited to an equal extent by optimal or suboptimal doses of anti-CD4 antibody administered 2 days after GaMD. Even a suboptimal, 50-micrograms dose of anti-CD4 antibody, when injected 5 days after GaMD, inhibited the IgE response to a much greater extent than did an optimal 10-mg dose of anti-IL-4 antibody injected at the same time, even though 10 mg of anti-IL-4 antibody more completely inhibited GaMD-induced IgE production than did 50 micrograms of anti-CD4 antibody when injected 2 days after GaMD. These observations provide evidence that a late acting form of T cell help other than IL-4 is important for the generation of an IgE response but not an IgG1 response in GaMD-immunized mice.