bluuebunny/crossref_metadata_2025 huggingface dataset:
Distinct role of neonatal and adult monocytes in the regulation of the in vitro antigen-induced plaque-forming cell response in man.
Authors: van Tol M J , Zijlstra J , Thomas C M , Zegers B J , Ballieux R E
Published: December 2022

Mononuclear cells from human cord blood (CBMC) are able to mount an antigen-specific IgM plaque-forming cell (PFC) response after primary in vitro stimulation with the T cell-dependent antigen ovalbumin (OA). The antigen dose-response relationship for the induction of PFC in cultures of CBMC is represented by a bell-shaped curve comparable to that found for mononuclear cells from adult peripheral blood (adult PBMC). The dose of OA optimal for the induction of a response in cultures of CBMC consistently, however, is 100-fold lower than the antigen dose optimal for adult PBMC (0.03 microgram OA/ml vs 3.0 micrograms OA/ml). Results obtained from co-culture experiments in which semiallogeneic combinations of parental/neonatal lymphocytes and monocytes were stimulated with a variable dose of OA indicate that the adherent cell (AC) plays a pivotal role in the establishment of the optimum antigen dose. From experiments using antigen-pulsed AC, it was concluded that neonatal and adult AC differ in their antigen handling capacity. In the presence of the prostaglandin synthetase inhibitor indomethacin the antigen dose-response relationship for the induction of PFC in cultures of CBMC shifts to an "adult type" of curve. From pulsing experiments it emerges that indomethacin affects the interaction between antigen and monocytes. Indomethacin causes an enhancement of the expression of HLA-DR at the surface of neonatal as well as adult AC; this can be down regulated by the addition of prostaglandin E2 (PGE2). The addition of PGE2 to cultures of adult PBMC leads to a shift of the optimal antigen dose for induction of PFC toward lower concentrations. Although higher levels of PGE2 were measured in the supernatant of cultured neonatal AC compared with adult AC, it seems unlikely that this observation can explain the distinct antigen dose-response relationship for the induction of a PFC response in cultures of CBMC.
Defective regulation of immune responses in respiratory syncytial virus infection.
Authors: Welliver R C , Kaul T N , Sun M , Ogra P L
Published: December 2022

The relationship of suppressor cell numbers and function to virus-specific IgE response was determined in 72 infants with respiratory syncytial virus (RSV) infection. Monoclonal antibodies to membrane antigens were used to enumerate OKT4 and OKT8 antigen-positive cells, and suppressor cell function as quantitated by the degree of suppression of lymphocyte mitogenesis induced by incubation of lymphocyte cultures with histamine. Patients with bronchiolitis had fewer OKT8-positive cells during convalescence than patients with other forms of illness due to RSV (p less than 0.05). An inverse correlation of OKT8-positive cell numbers and peak IgE titers was observed (p less than 0.01). Histamine-induced suppression was also reduced in patients with bronchiolitis (p less than 0.05). In patients with repeated infection, improved histamine-induced suppression was associated with reduced virus-specific IgE titers and the absence of wheezing. Defects in immunoregulation may underlie previously recognized immunologic and pharmacologic abnormalities in patients with bronchiolitis.
Affinity of phytohemagglutinin (PHA) isolectins for serum proteins and regulation of the lectin-induced lymphocyte transformation.
Authors: Glad C , Borrebaeck C A
Published: December 2022

The lectin (PHA) from Phaseolus vulgaris is a tetrameric glycoprotein composed of two different subunits (E and L). The lectin exists as five isolectins (L4, L3E, L2E2, LE3, and E4) that apparently originate from all possible tetrameric combinations of the two subunits. We have investigated two isolectins, PHA-E4 and PHA-L4, with respect to their affinity for human serum glycoproteins, and have subsequently determined how these interactions modulate the ability of the isolectins to induce lymphocyte transformation. PHA-E4 has affinity for 14 identified serum glycoproteins, whereas PHA-L4 exhibited affinity for nine of these proteins. IgM, IgA, IgG, alpha 2-macroglobulin, beta-lipoprotein, and haptoglobin showed the strongest reactivity with PHA-E4; haptoglobin, IgG, and IgA were also the best ligands for PHA-L4. The glycoprotein levels of human serum were then reduced by running the serum over PHA-E4 and PHA-L4 affinity columns, respectively, and the glycoproteins that bound to the two immobilized isolectins were eluted, pooled, and concentrated. The ability of PHA-E4 and PHA-L4 to activate human lymphocytes in the presence of (i) normal human serum, (ii) human serum with reduced levels of glycoproteins, and (iii) human serum with elevated levels of glycoproteins revealed a strong regulatory effect of the glycoproteins on the lymphocyte transformation. When the inhibitory glycoproteins and glycolipids were removed from serum, the mitogenic effect of PHA-E4 increased 200-fold, whereas PHA-L4 exhibited only a 25-fold increase in mitogenic activity. These results show that the so-called "erythroreactive isolectin (PHA-E4)" actually possesses a strong mitogenic activity of its own, but that this has been masked by the interference of serum components.
Macrophages release arachidonic acid, prostaglandin E2, and thromboxane in response to late complement components.
Authors: Hänsch G M , Seitz M , Martinotti G , Betz M , Rauterberg E W , Gemsa D
Published: December 2022

Rat peritoneal macrophages released arachidonic acid, prostaglandin E2, and thromboxane B2 when treated with normal rabbit or C6-deficient rabbit complement in vitro. Normal rabbit complement, however, was more efficient, which indicates that late complement components, in addition to the known effects of C3a and C3b, were responsible for an enhanced arachidonic acid turnover. Indeed, in the absence of the C3 cleavage products, the purified late complement components C5b6, C7, C8, and C9 stimulated the arachidonic acid, as well as the prostaglandin E2 and thromboxane B2 release. Incubation of C5b6, C7, C8, and C9 for 1 hr at 37 degrees C before addition to the macrophages abolished the stimulatory activity, being in complete agreement with the fact that a fluid phase-formed complex of C5-9 loses its membrane-binding capacity. Although the mechanism by which C5b-9-membrane interaction affects the arachidonic acid metabolism remains unclear, the data describe a new function of the late complement components.
Polyamine oxidase-mediated trypanosome killing: the role of hydrogen peroxide and aldehydes.
Authors: Ferrante A , Rzepczyk C M , Saul A J
Published: December 2022

Trypanosoma lewisi and T. musculi were lysed when incubated with bovine serum in the presence of either spermine or spermidine. Similar results were obtained when a fraction from bovine serum containing polyamine oxidase (PAO) activity or a commercially available purified beef plasma PAO were used in lieu of bovine serum. Trypanosomes treated with cytotoxic concentrations of PAO-spermine failed to establish infection in rats. These results are similar to those from our previous studies with African trypanosomes. We now extend the properties of PAO by showing that human retroplacental serum (RPS) containing PAO activity was also capable of mediating trypanosome killing. This is of significance because the macrophage PAO resembles the human RPS PAO. In addition, our preliminary studies, in which an attempt was made to characterize the factors responsible for cytotoxicity, suggested that a number of products of the PAO-polyamine reaction display trypanocidal properties. These included hydrogen peroxide (H2O2), the aldehyde acrolein, and possibly aminoaldehydes. No evidence was obtained that the oxygen intermediates, superoxide and hydroxyl radicals, play a role in the PAO-mediated trypanosome killing. Ammonia, an additional product of PAO-polyamine reaction, was not trypanocidal. Furthermore, the data suggested that less than 30 min exposure to the reaction mixture (and possibly to aminoaldehydes) was adequate to cause irreversible damage to trypanosomes.
Cytolytic T lymphocyte and antibody responses to synthetic peptides of influenza virus hemagglutinin.
Authors: Wabuke-Bunoti M A , Taku A , Fan D P , Kent S , Webster R G
Published: December 2022

Two peptides corresponding to HA1(181-204) and HA2(103-123) of the A/Japan/305/57 influenza virus hemagglutinin (HA) were chemically synthesized by solid-phase methods and were tested for their ability to generate murine secondary anti-influenza cytolytic T lymphocytes (CTL) in vitro and to bind monoclonal anti-HA antibodies. Peptide HA1(181-204) could only generate CTL in the presence of helper factors contained in supernatant fluids from either Concanavalin A-stimulated mouse spleen cultures or WEHI-3 cells grown in vitro. Peptide HA2(103-123) stimulated the induction of anti-influenza CTL independent of helper factors, but the stimulation was also greatly increased if helper factors were added. A 10-fold molar excess of peptide HA2(103-123) was required to obtain optimal CTL activation over the quantities required in the HA1(181-204) system. This molar ratio remained unchanged, even in the presence of helper factors. Induction of influenza-specific CTL was antigen-dependent in both systems, even though some killing of noninfected target cells was also occasionally observed. Our results suggest that synthetic peptides can be recognized as antigenic determinants in the generation of H-2-restricted anti-viral CTL capable of killing appropriately infected target cells. The inability of peptide HA1(181-204) to generate sufficient help for CTL development suggests that certain regions of the HA can be recognized by CTL precursors, but not by all of the required helper cells. Peptide HA1(181-204) also reacted with three monoclonal anti-HA antibodies as well as mouse anti-influenza (A/Japan/305/57) immune sera. This antibody reactivity suggests the possibility of a shared antigenic epitope or region between T and B cells, and therefore provides new insight in our understanding of viral antigenicity.
Renal deposits of lipoprotein-immunoglobulin complexes in Plasmodium chabaudi-infected mice.
Authors: Delvinquier B , Goumard P , Dubarry M , Tronchin G , Camus D
Published: December 2022

Lipoprotein metabolism is altered and immunoglobulin-lipoprotein complexes (Ig-Lp) are formed during malaria infection (1-5). Ig-Lp were detected in the sera of Plasmodium chabaudi-infected mice 9 days post-infection (1 or 2 days after parasitemia had peaked at about 50%) and reached a maximum on day 13 (when the parasitemia had decreased to less than 1%). Renal glomerular deposits of IgM were first detected at day 3 and were heavy from day 9 to day 29; deposits of IgG and low density lipoprotein (LDL) were present from days 9 to 62, and were more dense from days 22 to 29; deposits of C3 were observed from day 13 to day 29. Apoprotein B component was found in heparin eluates of kidneys on day 10, 14, and 29. Fractionated Ig-Lp, as well as whole sera from day-13 infected mice, were injected into uninfected mice that developed LDL glomerular deposits only when pre-treated with histamine. LDL glomerular deposits were also observed after i.v. injection of day-29 sera (containing free anti-lipoprotein antibody) into day-7 infected mice, but not when a mixture of day-29 and day-7 sera was injected into normal recipient mice. LDL glomerular deposits, however, were observed when recipient mice were treated with the Plasmodium-derived Insoluble Material (PDIM) 3 days before the injection of the day-29-day-7 sera mixture or day-13 serum. Two hours after the i.v. injection of 125I-Ig-Lp, the radioactivity of the kidneys was higher in histamine-treated, PDIM-treated, and P. chabaudi-infected mice than in controls. The clearance of 125I-Ig-Lp was higher in infected and in PDIM-treated mice than in controls. We suggest that the glomerular deposit of Ig-Lp that occurs during P. chabaudi infection requires an enhancing factor such as PDIM that is released during infection.
Reversible defect in antigen-induced lymphokine and gamma-interferon generation in cutaneous leishmaniasis.
Authors: Murray H W , Rubin B Y , Carriero S , Acosta A M
Published: December 2022

Peripheral blood mononuclear cells from a patient with progressive Leishmania mexicana (LM) infection were examined for responses to mitogen and antigen before, during, and after successful treatment. Before therapy, his cells proliferated normally and secreted effective macrophage-activating lymphokines in response to concanavalin A (Con A) and Toxoplasma gondii antigen, but failed to show any response to LM antigen. At this time, suppressive humoral factors were not present, the intracellular antimicrobial activity of the patient's monocytes was intact, and once stimulated with normal lymphokines, his monocyte-derived macrophages readily killed his own infecting LM strain. One month after initial treatment, the patient's T cells showed variable but measurable responses to LM antigen, and by 6 mo, these responses were fully developed in proliferative and lymphokine-generating assays. The patient's lymphokines were examined for gamma-interferon (IFN-gamma) because a) a monoclonal anti-human IFN-gamma antibody abolished the capacity of lymphokines to activate normal macrophages to kill LM, and b) partially purified and recombinant IFN-gamma alone could induce macrophage leishmanicidal activity. The patient's pretreatment Con A- and T. gondii antigen-stimulated lymphocyte supernatants (which activated macrophages to kill LM) contained 2000 to 3000 U/ml of IFN-gamma, whereas his LM antigen lymphokine was devoid of activity (less than 10 U/ml). At 1 and 6 mo after therapy, however, the latter lymphokine showed 20 and 600 U/ml of IFN-gamma, respectively, paralleling the development of antigen-specific proliferation and active lymphokine generation and the clinical status of his infection. These results appear to support previous suggestions that the ability of T cells to secrete antigen-induced macrophage-activating lymphokines (particularly IFN-gamma) is a key cellular immune response to intracellular Leishmania infections.
A monoclonal antibody (AE3.d3) with mitogenic properties for murine B cells.
Authors: Allouche M , Basch R S , Berman J W
Published: December 2022

A monoclonal antibody, AE3.d3, derived from the fusion of rat splenocytes immunized against mouse brain with the myeloma SP2, has been produced, which has the property of inducing the proliferation of mouse lymphocytes. The mitogenic effect is highest in spleen and lymph node cells, where up to a 10-fold stimulation of 3H-TdR incorporation is observed. B lymphocytes are the most susceptible to this proliferative stimulus, and they are induced to differentiate into plaque-forming cells. T lymphocytes and "null" cells (defined by the absence of Thy-1 or Ig on their surface) do proliferate, although to a smaller extent. The T cell subpopulation, isolated from either spleen or thymus, requires additional "helper factors" in order to proliferate. The mitogenic response is not genetically restricted by H-2 type, and strains such as C3H/HeJ and CBA/N, in which B cell function is defective, as well as T cell-deficient strains such as BALB/c nude mice, are capable of responding to the stimulus of AE3.d3. Using immunofluorescence, we also examined the distribution of AE3.d3-positive cells in various lymphoid organs. The highest percentage of stained cells is found in the spleen (approximately 28%) and lymph node (18%), whereas only 14% of the bone marrow and 5% of the cells of the thymus are brightly stained with AE3.d3.
Defective T cell response to presented antigen in autoimmune mice.
Authors: Fischbach M
Published: December 2022

The effect of the single autosomal recessive gene lpr on antigen presentation was studied. MRL/Mp-lpr/lpr, C3H/HeJ-lpr/lpr, C57BL/6J-lpr/lpr, and their normal congenic partners were investigated. Mice bearing the lpr gene were unable to respond to TNP-KLH when presented by syngeneic antigen-presenting cells. The congenic normal partners gave a brisk response. Mixing experiments demonstrated that the defect resided with the lpr responding T cell and not with the lpr antigen-presenting cell. Antigen-presenting cells from lpr mice were capable of inducing T cell proliferation in normal congenic partners, whereas antigen-presenting cells from normal mice failed to stimulate lpr T cells. This defect was intrinsic to an Lyt-1+2- cell. Pharmacologic restoration was attempted by in vivo and in vitro administration of interleukin 2. However, cells from lpr mice remained unaffected. The relationship of these findings to autoimmunity is discussed.
Peripheral (somatic) expansion of the murine cytotoxic T lymphocyte repertoire. I. Analysis of diversity in recognition repertoire of alloreactive T cells derived from the thymus and spleen of adult or aged DBA/2J mice.
Authors: Chang M P , Gorczynski R M
Published: December 2022

Cytotoxic T lymphocyte precursors (CTLp) in the spleen or thymus of individual adult (8 to 10 wk) or aged (greater than 20 mo) DBA/2J mice have been activated by irradiated H-2Kb antigens under limiting dilution conditions such that cytotoxic cells in responder wells result from stimulation of a single CTLp. After division into several equal samples and expansion in the presence of IL 2 and more irradiated H-2Kb stimulators, the contents of replicate individual wells were tested for their ability to lyse a panel of selected H-2Kb mutant targets. The heterogeneity within a given age group, and the similarity of CTLp repertoires between different age groups were then compared for splenic and thymic CTLp repertoires. Our data indicate a far greater mouse-to-mouse variation for the splenic CTLp repertoire of aged mice compared with young mice, despite the greater heterogeneity of the repertoire in the latter case. Less difference was seen for the thymic CTLp repertoire. When we studied the correlation between the repertoires present in the thymus and spleen within a given age group, it seemed that the most striking difference in aged mice was a loss of systematic expansion of the early appearing thymic CTLp repertoire. These findings are discussed in terms of a two-stage model of T cell differentiation.
Delayed-type hypersensitivity is mediated by a sequence of two different T cell activities.
Authors: Van Loveren H , Askenase P W
Published: December 2022

Classical 24- to -48 hr delayed-type hypersensitivity (DTH) skin reactions are preceded by an early skin swelling reaction that peaks 2 hr after challenge. The ability to elicit this early component of DTH is T cell dependent and is also dependent on tissue mast cells and release of serotonin, mainly from these mast cells. The current study presents pharmacologic and kinetic evidence that the late response depends on the occurrence of the early response. A variety of pharmacological agents known to deplete, prevent release of, or block the activity of serotonin, when given just before skin challenge, blocked both the early and late components of DTH, but had no effect when given (even repeatedly) after the occurrence of the early component. Thus, the serotonin-dependence of the 24-hr component of DTH represents a dependence on the early component in which serotonin release is required. A temporal dependence of the late component of DTH on the early component was also demonstrated. The early and late phases occur at different times in recipients of sensitized T cells, depending on the interval between transfer and challenge, but there is a fixed 10- to 12-hr gap. Delayed onset of the late component occurs in recipients challenged immediately after transfer and appears to be due to a delay in the onset of the early component. This delay can be abolished by adoptive cell transfer into mice that are able to elicit a normal early component because of prior transfer of T cells that are able to mediate just an early component. On the basis of these findings, we conclude that DTH consists of a cascade of events. T cells mediating the early aspect of DTH release antigen-specific factors that, upon encountering antigen activate local serotonin-containing cells, such as mast cells, to release serotonin, which opens gaps between adjacent endothelial cells. Through these interendothelial gaps a second T cell population enters the extravascular space and interacts with local antigen to induce the late response by releasing the chemoattractant lymphokines that are classically associated with DTH and that cause recruitment of bone marrow-derived circulating leukocytes to infiltrate the reaction site. The ability of the second T cell population to mediate the late component of DTH is independent of further release of serotonin.
Morphologic and phenotypic features of the subpopulation of Leu-2+ cells that suppresses B cell differentiation.
Authors: Clement L T , Grossi C E , Gartland G L
Published: December 2022

The Leu-2 antigen is expressed on a subpopulation of human T cells that perform suppressor and cytotoxic functions. In addition, this antigen is also present on a portion of cells with morphologic characteristics of granular lymphocytes. Although both Leu-2+ cells and granular lymphocytes have been shown to suppress B cell differentiation, the interrelationship of these two suppressor populations has not previously been fully characterized. We recently produced a monoclonal antibody, termed D12 (anti-Leu-15), which reacts with a variety of cell types, including a subpopulation of Leu-2+ cells. Previous studies have indicated that the Leu-2+ cells that suppress T cell proliferative responses express the Leu-2+15+ phenotype, whereas the precursor and effector cytotoxic T cells that recognize class I major histocompatibility antigens are Leu-2+15- lymphocytes. For this report, we used the anti-Leu-2 and anti-Leu-15 monoclonal antibodies and fluorescence-activated cell sorter techniques to characterize the E+ cells that suppress PWM-induced B cell differentiation. These studies indicate that the vast majority of Leu-2+ cells that suppress this T cell-dependent B cell response have the Leu-2+15+ phenotype. Furthermore, when the morphologic and cytochemical characteristics of these Leu-2+15+ cells were studied, virtually all of these cells were granular lymphocytes. Most of the Leu-2+15+ suppressor cells co-expressed the HNK-1 (Leu-7) antigen, which is detected only on granular lymphocytes. In contrast, virtually none of the Leu-2+15+ granular lymphocytes expressed Fc receptors for IgG molecules. These data indicate that the Leu-2+ cells that suppress PWM-induced B cell differentiation are Leu-2+15+ (and predominantly Leu-7+) granular lymphocytes that do not express Fc receptors. The implications of these observations concerning the relationship of human Leu-2+ suppressor cells to murine Ly-2+ cells and the lineage of granular lymphocytes are discussed.
Anti-immunoglobulin autoantibodies are not preferentially induced in polyclonal activation of human and mouse lymphocytes, and more anti-DNA and anti-erythrocyte autoantibodies are induced in polyclonal activation of mouse than human lymphocytes.
Authors: Dziarski R
Published: December 2022

Using a plaque assay with immunoglobulin (Ig)-coated SRBC, we and others have previously reported that the majority of polyclonally activated mouse lymphocytes secreted antibodies that appeared to be IgM anti-IgG autoantibodies. Careful reexamination of this assay, with application of several highly purified mouse serum and myeloma IgG and IgM preparations, revealed that IgM, which was a minor contaminant of Ig preparations, rather than IgG, was responsible for the formation of these plaques. High numbers of plaques could also be detected in assays with polyclonally activated human lymphocytes, Ig-coated SRBC, and anti-Ig developing sera. Of all IgG-, IgM- or IgA-secreting cells, 40 to 100% were detected with SRBC coated with gamma-globulin or Ig of the same isotype as the isotype to which the developing serum was specific; in general, low proportions of all PFC were detected with SRBC coated with Ig of a different isotype. Studies on the sequence of events leading to the formation of plaques with Ig-sensitized SRBC (both in humans and mice) revealed that antibodies detected in these assays were not able to bind to the Ig-coated SRBC (without the presence of developing serum), and therefore were not anti-Ig autoantibodies. It is our conclusion that the plaque assays with Ig-coated SRBC represent another type of a reverse hemolytic PFC assay that detects cells secreting antibodies regardless of their specificity, and these plaques are formed due to the cross-linking by the anti-Ig developing serum of the Ig coated on SRBC and the Ig secreted by lymphocytes. Our results confirmed preferential induction of anti-DNA antibody secreting cells in mice by showing that these antibodies indeed bind to DNA coated on SRBC. In cultures of polyclonally activated human lymphocytes, anti-DNA and anti-erythrocyte autoantibody-secreting cells were over 10 to 100 times less frequent than in mice. These results, therefore, disprove the concept of preferential induction of anti-Ig autoantibodies in the polyclonal activation of mouse and human lymphocytes, and show that anti-DNA and anti-erythrocyte autoantibodies are easily induced in the polyclonal activation of mouse, but not human, lymphocytes.
Monoclonal anti-histone autoantibodies derived from murine models of lupus.
Authors: Kotzin B L , Lafferty J A , Portanova J P , Rubin R L , Tan E M
Published: December 2022

We characterized three monoclonal antibodies with histone reactivity which were derived from spleen cells obtained from unmanipulated NZB/NZW or MRL/1 mice. By using an enzyme-linked immunosorbent assay, we noted that all three antibodies reacted with chromatin histones as well as with total histones extracted from chromatin. None of the antibodies appeared to require DNA as part of the antigen. One antibody (BWH-1) recognized a determinant present in the nucleosome core H2A-H2B complex but showed little reactivity with any of the individual histones (H1, H2A, H2B, H3, or H4). In contrast, the other two monoclonal antibodies each recognized multiple individual histones in a unique pattern. Antibody MH-1 reacted with H2A, H2B, and H3; antibody MH-2 reacted with H2A, H3, and H4. MH-1 demonstrated cross-reactivity with poly-1-lysine but not poly-1-arginine or protamine sulfate; the opposite pattern of cross-reactivity was observed with MH-2. The antigenic determinants recognized by MH-2 were all trypsin-sensitive, suggesting that these determinants were present on the N-terminal regions of the respective individual histones. These studies revealed markedly different specificities of anti-histone monoclonal antibodies derived from murine models of systemic lupus erythematosus. These and other similarly derived antibodies may provide interesting tools to understand the specificity and biologic importance of anti-histone autoantibodies in different diseases.
Spontaneous interstitial nephritis in kdkd mice. I. An experimental model of autoimmune renal disease.
Authors: Neilson E G , McCafferty E , Feldman A , Clayman M D , Zakheim B , Korngold R
Published: December 2022

Mice of the kdkd strain predictably develop a spontaneous tubulointerstitial nephritis after 8 wk of life. In this report we have examined several aspects of the nephritogenic immune response that seemed potentially relevant to the expression of this progressively destructive renal lesion. Of particular interest is that by direct immunofluorescence we were unable to demonstrate the presence of antibodies to determinants in the tubulointerstitium. Serum and kidney eluates from nephritic mice, furthermore, did not stain any renal structures in normal kidney. We did observe, however, that disease could be transferred through kdkd----CBA/Ca bone marrow chimeras, and prevented, in the reverse direction, by CBA/Ca----kdkd chimeras. The development of the interstitial lesion was markedly inhibited by thymectomy with T cell depletion, but disease could not be adoptively transferred with cells or serum from nephritic mice. The interstitial lesions also did not appear in (kdkd X CBA/Ca)F1 hybrids, and the development of disease in kdkd mice could be inhibited by treatment with adoptively transferred T cells from CBA/Ca mice. With these new findings we now hypothesize that susceptibility to the expression of interstitial nephritis in kdkd mice involves the cellular limb of the immune system, and may be related, in part, to alterations in regulatory T cell function.
Idiotypic analysis of anti-I-Ak monoclonal antibodies. II. Detection of shared idiotopes on syngeneic BALB/c and allogeneic A.TH-derived anti-I-Ak mAb by BALB/c-derived anti-I-Ak anti-idiotypic mAb.
Authors: Devaux C A , Phillips M L , Delovitch T L
Published: December 2022

The IA2, IIID1, and VC6 BALB/c-derived anti-11-5 anti-idiotypic (anti-Id) monoclonal antibodies (mAb) described in the companion paper were used to study the idiotopes expressed by a panel of 13 anti-I-Ak and 10 anti-I-Ek mAb. IA2 and IIID1, which detect binding-site-related idiotopes of the syngeneic BALB/c-derived 11-5 mAb, each react with public idiotope(s) (IdX) of two allogeneic A.TH-derived anti-I-Ak mAb (8B and 39J). VC6, which detects an 11-5 idiotope that differs from the IA2 and IIID1 idiotopes, binds to the 8B but not the 39J mAb. The three anti-Id mAb examined do not bind to idiotopes on 11 other anti-I-Ak or to 10 other anti-I-Ek mAb tested. These data demonstrate that mice immunized with a murine anti-I-Ak mAb probably produce syngeneic anti-IdX serum antibodies. Furthermore, they suggest that the 11-5 IdX markers identified are shared by alloantibodies of the BALB/c (Igh1a) and A.TH (Igh1e) mouse strains and may be expressed independently of Igh-C allotype markers. The sharing of idiotopes between the 11-5, 8B (anti-Ia.2), and 39J (anti-Ia.19) mAb led us to reinvestigate the antigenic specificity of the 11-5 mAb and the genetic complexity of the serologically detectable Ia.2 and Ia.19 epitopes present on I-Ak molecules. Two main points emerge from these studies. First, the 11-5 BALB/c-derived anti-I-Ak mAb, previously considered to have an anti-Ia.2 specificity, was shown by direct binding and competition binding assays to possess instead a reactivity pattern more compatible with that of an anti-Ia.19 mAb. Second, the anti-Ia.2 and anti-Ia.19 mAb, which were provisionally considered to bind epitopes in a single region of an I-Ak molecule, termed epitope cluster IV, actually define at least four different subgroups of this cluster. These subgroups are designated as IV A-D, and IV D is detected by the 11-5 and 39J anti-Ia.19 mAb. This tentative subdivision of I-Ak epitope cluster IV suggests there exists a minimum of seven topologically distinguishable regions of an I-Ak molecule that give rise to polymorphic allodeterminants, some or all of which may mediate lymphocyte interaction.
Monoclonal antibody to murine neutrophils: identification of the Gm-2.2 specificity.
Authors: Hibbs M L , Hogarth P M , Scott B M , Harris R A , McKenzie I F
Published: December 2022

A neutrophil-specific alloantigen (Gm-2.2) was defined by a monoclonal antibody, 5119-4/7. The Gm-2.2 antigen is found only on bone marrow neutrophils or calcium caseinate-induced neutrophils and is absent from all lymphoid cells examined as well as adherent thioglycollate-induced peritoneal exudate cells and the nonhemopoietic tissues, kidney, liver, heart, brain, and red blood cells. Furthermore, unlike mature neutrophils, granulocyte/macrophage progenitor cells are Gm-2.2-, suggesting that Gm-2.2 is a differentiation antigen for the neutrophil series. The Gm-2 locus is linked to, but distinct from, the Ly-6 locus.
C3d-K, a kallikrein cleavage fragment of iC3b is a potent inhibitor of cellular proliferation.
Authors: Thoman M L , Meuth J L , Morgan E L , Weigle W O , Hugli T E
Published: December 2022

The C3d-K fragment generated from human iC3b by plasma kallikrein is a potent suppressant of cellular proliferation. Originally characterized as inhibiting human and murine T lymphocyte function, C3d-K is shown in these studies to suppress mitogen-induced B cell growth, the spontaneous proliferation of several tumor cell lines, as well as all forms of T cell proliferation, including that induced by interleukin 2 (IL 2). In addition, synthesis of IL 2 in mixed lymphocyte cultures is blocked by C3d-K, but not IL 2 synthesis induced by Con A. The C3d-K fragment has no effect on resting cells; however, sensitivity to the inhibitory effect of C3d-K is acquired during the activation process. Because the proliferation of mitogen-activated spleen cells is not inhibited by exposure to C3d-K for the initial 24 hr of culture, only late steps in the cell activation process are C3d-K sensitive. When C3d-K is present throughout the course of the 72-hr culture, suppression was observed. Data obtained with the tumor cell lines suggest that once suppression is achieved, it is long-lasting even in the absence of C3d-K.
Properties of prostaglandin-sensitive adenylate cyclase system of a murine macrophage-like cell line (P388D1).
Authors: Fernandez-Botran R , Suzuki T
Published: December 2022

The properties of basal and prostaglandin (PG)-stimulated adenylate cyclase of membrane preparations of P388D1 cells were investigated. Three partially purified membrane fractions were obtained by sucrose density gradient centrifugation at the final step of purification from crude homogenate. About 96% of the basal and 89% of PGE2-stimulated adenylate cyclase activity in the homogenate were recovered in three membrane fractions. Two lighter membrane fractions (I and II), which were enriched 11-fold and 8.4-fold in adenylate cyclase activity over crude homogenate, were pooled and subjected to various studies. Results suggested that the basal activity of the membrane preparations has, as in many other cell types, a relatively broad pH optimum (pH 7.5 to 8.5), requires Mg2+, which must be present in excess ATP, and is inhibited by Ca2+. Highly reactive sulfhydryl group(s), which may be present in the lipid bilayer, is required for the adenylate cyclase activity. Because both fluoride ions and GTP augment the enzymatic activity, P388D1 cell membrane adenylate cyclase must possess stimulatory guanine nucleotide-binding protein. The membrane preparations respond to exogeneously added PG by 1.5-fold to 3-fold increase in adenosine 3'-5' cyclic monophosphate (cAMP) production. The magnitude of PG-responsiveness was dependent on the types of PG and the order of potency in stimulation was PGE1 greater than PGE2 greater than PGI2. PGA1, B1, B2, F1 alpha, and F2 alpha stimulated adenylate cyclase only at the highest concentration tested.
Melittin-specific monoclonal and polyclonal IgE and IgG1 antibodies from mice.
Authors: King T P , Kochoumian L , Joslyn A
Published: December 2022

Melittin, a bee venom peptide consisting of 26 amino acid residues, elicited high IgG and IgE antibody responses in mice of BALB/c and CAF1 strains, but not in mice of A/J, AKR, and C57BL/6 strains. Greater than 80% of the melittin-specific antibodies in sera of responder mice were found to bind the hydrophilic carboxyl-terminal heptapeptide of melittin. Three melittin-specific monoclonal antibodies were obtained from responder mice by the hybridoma technique. Two are of the IgG1 isotype and one is of the IgE isotype. One monoclonal antibody of the IgG1 isotype binds the carboxyl-terminal heptapeptide of melittin, while the other two monoclonal antibodies do not. However, competitive binding studies suggest that all three monoclonal Ig bind at the same, or adjacent, site of melittin. These findings, together with the known amphiphilic property of melittin, suggest that the immunogenicity of this peptide is a consequence of its binding to cell surface phospholipids.
Humoral immunity in experimental syphilis: the demonstration of IgG as a treponemicidal factor in immune rabbit serum.
Authors: Blanco D R , Miller J N , Hanff P A
Published: December 2022

The neutralizing activity present in immune rabbit serum (IRS) against virulent Treponema pallidum was shown to be mediated by IgG and complement. IgG was isolated and purified from both IRS and nonimmune rabbit serum (NRS) by the use of an affinity system in which staphylococcal protein A was conjugated to Sepharose 4B. The purity of the isolated IgG fractions was demonstrated by both immunoelectrophoresis and SDS-polyacrylamide gel electrophoresis. Fractions of IgG were tested for specific neutralizing activity as measured by an in vitro-in vivo neutralization test. Lesions failed to develop at 80% of the sites inoculated with treponemal suspensions containing IgG from IRS in the presence of unheated NRS as a source of complement; delayed atypical lesions were observed at the remaining sites. In contrast, typical lesions developed at all sites inoculated with suspensions containing IgG from IRS in the presence of heated NRS. They were significantly delayed, however, as compared with lesion development at control sites inoculated with suspensions containing IgG from NRS. These results provide the first direct evidence for an IgG complement-mediated treponemicidal mechanism operative in immune serum from rabbits with latent syphilis.
Modulation of macrophage activation and resistance by suppressor T lymphocytes in chronic murine Schistosoma mansoni infection.
Authors: Olds G R , Ellner J J
Published: December 2022

Activated macrophages (M phi) appear responsible for at least part of the concomitant resistance in mice infected with Schistosoma mansoni. We found that as murine S. mansoni progressed from acute (8 to 12 wk of infection) to chronic (16 to 24 wk) stages, acquired resistance decreased (57% resistance to challenge with cercariae at 8 wk vs 28% by 24 wk, p less than 0.05), as did macrophage activation (21% +/- 2 killing of schistosomula by 8 wk M phi vs 8% +/- 2 for 24 wk M phi, p less than 0.01). T cells from the spleens of 8 wk-infected mice were capable of activating M phi from naive animals when stimulated with worm antigens (24% +/- 2 killing vs 8% +/- 2 induced by normal T cells, p less than 0.01); T cells obtained from 24 wk-infected mice did not activate M phi (13% +/- 2 killing). Furthermore, T cells from 24 wk-infected animals suppressed activation of M phi by 8 wk T cells. The addition of 10(5) 24 wk T cells to 3 X 10(5) antigen-stimulated 8 wk T cells reduced subsequent M phi killing from 27% +/- 4 to 13% +/- 2 (p less than 0.05). Week 24 T cells (3 X 10(5] reduced this additionally to 9% +/- 1 (p less than 0.01), a value no greater than that of unstimulated M phi. The subpopulation of T cells responsible for suppression of M phi activation was Lyt-2+1- nonadherent T cells. Cyclophosphamide treatment of chronically infected mice resulted in enhanced resistance (41%), M phi activation (18% +/- 1 killing), and T cell activation of naive M phi (10% +/- 1 killing). Thus, during chronic S. mansoni infection, resistance to reinfection wanes in parallel to and perhaps because of development of suppressor T cells that interfere with T-dependent M phi activation.
Immunotherapy of lymphoid and nonlymphoid tumors with monoclonal anti-Lyt-1 antibodies.
Authors: Hollander N
Published: December 2022

Monoclonal antibodies against the T cell differentiation antigen Lyt-1 were effective in the therapy of transplanted mouse tumors. A possible mechanism whereby anti-Lyt-1 antibodies directly bind and affect the tumor cells was excluded by the following findings: a) growth of lymphoid and nonlymphoid tumors (which lack Lyt-1 antigen) was affected by anti-Lyt-1 antibodies; and b) the curative effect of passively administered anti-Lyt-1 anti-bodies was abrogated in mice depleted of T cells, supporting a mechanism whereby host Lyt-1+ cells were involved in tumor therapy. Treatment with anti-Lyt-1 antibodies was not accompanied by depletion of Lyt-1+ cells from lymphoid organs, indicating that the administered antibodies altered Lyt-1+ cell functions without affecting their frequency. In view of the in vitro enhancing effects of anti-Lyt-1 antibodies on a variety of immune responses (including lymphokine secretion and generation of cytotoxic T cell), it is suggested that the potentiation of Lyt-1+ cell activity by passively administered anti-Lyt-1 antibodies results in tumor rejection.
B cell activation. VI. Effects of exogenous diglyceride and modulators of phospholipid metabolism suggest a central role for diacylglycerol generation in transmembrane signaling by mIg.
Authors: Coggeshall K M , Cambier J C
Published: December 2022

Previous evidence indicates that in vitro activators of protein kinase C, such as phorbol myristate acetate (PMA), are able to induce early activation events in murine B cells, including membrane depolarization and increased I-A antigen expression. These same events are induced by specific antigen and anti-receptor antibody. This evidence suggests that protein kinase C activation may be an important intermediary event in mIg-mediated transmembrane signaling. Previously, investigators have suggested that protein kinase C activation is regulated by a novel second messenger, diacylglycerol (DG), and DG is generated by phosphatidylinositol (PI) hydrolysis after receptor-ligand interaction in many systems. In view of this concept, we examined the effects of nonspecific activators and inhibitors of DG production and DG itself on membrane potential and levels of I-A antigen expression in murine B cells. Our results indicate that exposure to DG, or induction of DG production by treatment of B cells with exogenous phospholipase C, results in depolarization and increased I-A antigen expression similar to that induced by anti-receptor antibody and specific antigen. Furthermore, we demonstrate that depolarization and increased I-A expression induced by anti-receptor antibody is blocked under conditions in which DG production is inhibited. As expected, based on its direct activation of protein kinase C, PMA stimulation is unaffected by this inhibition. These results support our earlier hypothesis that occupancy of antigen receptors on B cells is linked to subsequent activation events by PI hydrolysis, DG generation, and protein kinase C activation.
In vivo administration of purified human interleukin 2. I. Half-life and immunologic effects of the Jurkat cell line-derived interleukin 2.
Authors: Lotze M T , Frana L W , Sharrow S O , Robb R J , Rosenberg S A
Published: December 2022

A total of 12 patients with cancer or the acquired immunodeficiency syndrome have been treated with Jurkat-derived purified human interleukin 2 (IL 2). The toxicity was dose-related and consisted primarily of fever, chills, malaise, and mild reversible hepatic dysfunction. No evidence of clinical efficacy was seen when IL 2 was administered at doses of up to 2000 micrograms by bolus or continuous infusion once a week for 4 wk. No significant chronic immunologic effects (changes in mitogen responsiveness of induction of cytotoxic cells) were demonstrated. IL 2 was measured in the serum of patients, and a half-life of approximately 5 to 7 min was demonstrated with a second component of clearance of 30 to 120 min. Heating the serum at 56 degrees C for 30 min allowed for detection of smaller quantities of IL 2 by removing a serum inhibitor whose effect was seen at dilutions of up to 1/80 in our biologic assay. Sustained levels of IL 2 could be maintained by continuous infusion. Acute effects of IL 2 administration included a rapid decrease in peripheral mononuclear cells with a shift to cells of macrophage lineage and a rapid decrease in total T lymphocytes and T lymphocyte subsets. IL 2 responsiveness of peripheral mononuclear cells decreased within 15 min of IL 2 administration, with a concurrent decrease in the ability to generate lymphokine-activated killer cells. These changes did not recover until 48 hr after IL 2 administration. A rise in serum ACTH and cortisol levels was seen after the administration of 1 to 2 mg of IL 2. Future studies will evaluate the role of larger quantities of recombinant IL 2 given alone or in conjunction with in vitro-generated lymphokine-activated killer cells.
Immunoregulatory T cell circuits in man. Identification of a distinct T cell subpopulation of the helper/inducer lineage that amplifies the development of alloantigen-specific suppressor T cells.
Authors: Damle N K , Mohagheghpour N , Kansas G S , Fishwild D M , Engleman E G
Published: December 2022

Regulation of the immune response in man is dependent on interactions between cells of helper/inducer (Leu-3+/T4+) lineage and cells of suppressor/cytotoxic (Leu-2+/T8+) lineage. By using the mixed leukocyte reaction (MLR) as a model system, we have shown previously that alloantigen-primed Leu-3+ cells induce autologous Leu-2+ cells to differentiate into suppressor T cells that specifically inhibit the response of fresh T cells to the original allogeneic stimulator cells. The current study was undertaken to analyze the roles in this suppressor circuit of subpopulations of Leu-3+ cells distinguished from one another on the basis of their binding or lack of binding to monoclonal anti-Leu-8 antibody. Although both Leu-3+,8- and Leu-3+,8+ T cells proliferated in allogeneic MLR, alloactivated Leu-3+,8+ cells alone induced proliferation and differentiation of Leu-2+ suppressor cells. Leu-3+,8+ cells also induced Leu-3+,8- cells to proliferate, and following their activation in this manner, such autoactivated Leu-3+,8- cells augmented the differentiation of Leu-2+ suppressor cells, but only in the presence of alloactivated Leu-3+,8+ cells. Furthermore, this effect, like the suppressor effect, was specific for the inducer cells, and thus indirectly for the HLA-DR antigens of the original allogeneic stimulator cells as well. These results indicate that alloantigen-primed Leu-3+,8+ cells not only activate specific Leu-2+ suppressor cells but also activate specific Leu-3+,8- suppressor-amplifier cells, and in combination, these cells exert potent feedback inhibition of MLR.
The human thymic microenvironment. Phenotypic characterization of Hassall's bodies with the use of monoclonal antibodies.
Authors: Lobach D F , Scearce R M , Haynes B F
Published: December 2022

The human thymic microenvironment is important in promotion of T cell maturation, particularly during early stages of thymic ontogeny. Hassall's bodies (HB) are epithelial swirls in the human thymic medulla that are thought to be derived from endocrine medullary thymic epithelium. To study the ontogeny and function of various components of the human thymic microenvironment, we have produced four monoclonal antibodies (TE-8, TE-15, TE-16, and TE-19) that selectively reacted in thymus with HB. Antibodies TE-8 and TE-16 reacted with the cells forming the outer rim of the HB swirl. Antibody TE-19 reacted with the entire cellular portion of HB and with epithelial cells immediately surrounding HB. Granular foci in the cellular swirls of greater than 90% of HB reacted with antibody TE-15. During thymic ontogeny, the antigens defined by antibodies TE-8, TE-15, TE-16, and TE-19 were first detected in fetal thymus on HB beginning at 16 wk gestation, the age when HB morphologically appear in the thymus. Aberrant expression of the antigens corresponding to antibodies TE-8, TE-15, TE-16, and TE-19 was observed on thymic tissue from individuals with severe cellular immunodeficiency disease. In human skin, antibodies TE-8, TE-16, and TE-19 reacted with the stratum granulosum; antibody TE-15 reacted with the stratum corneum. Thus, with the use of antibodies TE-8, TE-15, TE-16, and TE-19, we have identified HB as antigenically distinct regions of endocrine thymic epithelium. Furthermore, we have shown that these anti-HB reagents also selectively react with epidermal keratinocytes in the terminal stages of keratinocyte maturation.