bluuebunny/crossref_metadata_2025 huggingface dataset:
Alloreactive T cells from individual soft agar colonies specific for guinea pig Ia antigens. I. Production and initial characterization.
Authors: Malek T R , Clark R B , Shevach E M
Published: December 2022

Allo-reactive T cells reactive with Ia antigens from strain 2 and 13 guinea pigs were cloned by plating T cells from primary mixed leukocyte cultures in soft agar and expanding the resulting colonies in liquid culture. Optimal expansion of the cultures from an individual colony was achieved by repeated stimulation with allogeneic cells in conditioned media. Mapping studies using stimulator cells from inbred and outbred guinea pigs and blocking studies with alloantisera and xenogeneic monoclonal antibodies to guinea pig Ia antigens indicated that these T cell colonies were specifically stimulated to proliferate by Ia molecules. In addition, these xenogeneic monoclonal anti-Ia antibodies had selective and differential inhibitory effects on the proliferative response of these alloreactive colonies. This result suggested that each T cell colony is specific for a distinct epitope expressed on Ia molecules. Furthermore, unlike heterogeneous cell populations in guinea pig primary and secondary mixed leukocyte cultures, most alloreactive T cell colonies expressed significant cytotoxic T lymphocyte activity that was also specific for Ia. Thus, the same cell proliferating to Ia is also a T killer cell. These T cell colonies will be useful for further analysis of the specificity and functional significance of the T cells responding in the mixed leukocyte reaction.
Alterations in T gamma cells in patients with chronic idiopathic thrombocytopenic purpura.
Authors: Trent R , Adams E , Erhardt C , Basten A
Published: December 2022

The number and percentage of T cells bearing Fc gamma receptors (T gamma) was quantitated in peripheral blood of patients with the autoimmune disease chronic ITP. In over half the patients, low initial percentages were obtained, the great majority of which returned to within the normal range after incubation under capping conditions. The phenomenon could be reproduced by pretreating normal T cells with immune complex containing sera or aggregated HGG. Furthermore, a reversible reduction in T gamma cells was observed in control patients with nonimmune thrombocytopenia and in pregnancy. In each case an association was observed between the reduced T gamma cell levels and the presence of circulating immune complexes, which suggested that the results could be explained by masking of Fc gamma receptors with preformed IgG-containing complexes. By contrast, patients with other autoimmune diseases such as scleroderma and rheumatoid arthritis had high or normal numbers of T gamma cells, respectively. Taken together, the findings do not support the existence of a gross deficiency of suppressor cells in patients with autoimmune disease and emphasize the need for caution in selection of markers for identification of T cell subsets.
Purification and radiolabeling of human C1q.
Authors: Tenner A J , Lesavre P H , Cooper N R
Published: December 2022

A new procedure for isolating human C1q from serum or plasma is described. The method, that is highly selective, rapid and involves minimal handling, yields fully active, immunoglobulin-free unaggregated C1q. Several different methods of radiolabeling C1q are compared. These include two methods selective for tyrosine residues, two that label lysine residues, and a method that labels sialic acid residues. The effect of each of the labeling procedures on C1q hemolytic activity was assessed. Also appraised for each method was the ability of the labeled molecules to bind to antibody sensitized cells and to interact with C1r and C1s to form C1. The distribution of each of the radiolabels among the three polypeptide chains of C1q and between the collagenous and globular regions of C1q was determined. Methods were identified that selectively labeled the globular portion of either the A or C polypeptide chain of the C1q molecule without loss of functional activity. Another of the methods labeled all three polypeptide chains relatively uniformly without significant loss of activity.
Specific haplotype preference in congenic F1 hybrid mice in the cytotoxic T cell response to the male specific antigen H-Y.
Authors: Müllbacher A , Sheena J H , Fierz W , Brenan M
Published: December 2022

Haplotype preference in the cytotoxic T cell response to H-Y in B10 congenic mice is only found in (B10 X B10.S)F1 hybrids. (B10 X B10.BR)F1 and (B10 X B10.D2)F1 do not generally show haplotype preference. H-2s is the preferred haplotype in H-Y immune (B10 X B10.S)F1 Tc cells. This haplotype preference is antigen specific since no preference was observed in the anti-influenza responses in (B10 X B10.S)F1 hybrids. Feedback inhibition as an explanation for haplotype preference could be excluded, but cross-reactivity of B10 H-Y immune Tc cells on B10.S targets suggests that natural tolerance may be responsible for haplotype preference.
The induction of tolerance and suppression in autoimmune MRL mice using hapten-modified self.
Authors: Santoro T J , Scott D W , Pisetsky D S
Published: December 2022

Disturbances in suppressor cell function have been considered important in the pathogenesis of systemic lupus erythematosus (SLE), a conclusion supported by studies with New Zealand mice. To determine whether other SLE mice display similar immunoregulatory defects, we investigated the susceptibility of autoimmune MRL mice to unresponsiveness induced by hapten-modified self (HMS). The response of splenocytes from MRL-lpr/lpr mice (lpr) was compared with those of sex- and age-matched, congenic MRL-+/+ mice (+/+), and H-2-identical (H-2k) CBA/J mice. Spleen cells (NSC) were cultured in vitro with hapten-modified syngeneic splenocytes (TNP-SC) and tested for responsiveness to TNP-LPS (for tolerance) or their ability to suppress the response of fresh cells. There was no difference in the susceptibility of lpr splenocytes from 3- and 10-mo-old mice to the induction of tolerance or suppression when compared with those from age-matched +/+ or CBA mice. To evaluate any quantitative defects in the responsiveness of lpr splenocytes to HMS, we modified the conditions under which suppressor activity was generated. Varying the ratio of NSC to TNP-SC from 10:1 to 2000:1, or changing the concentration of TNBS for haptenation from 10 mM to 0.5 mM per 10(8) spleen cells revealed no differences in the dose-response curves of lpr splenocytes for both tolerance and suppression when compared with those of the CBA. These results indicate that clinically affected MRL mice have intact suppressor cell activity in response to antigen-modified self and suggest a possible therapeutic role of this modality in inducing tolerance to self-antigens.
Selective desensitization of neutrophils: further studies with 1-O-alkyl-sn-glycero-3-phosphocholine analogues.
Authors: O'Flaherty J T , Lees C J , Miller C H , McCall C E , Lewis J C , Love S H , Wykle R L
Published: December 2022

Human polymorphonuclear neutrophils aggregate and degranulate in response to 2 recently described platelet-activating phospholipids: 1-O-alkyl-2-O-acetyl-sn-glycero-3-phosphocholine and 1-O-alkyl-2-O-ethyl-sn-glycero-3-phosphocholine. Here, we find that the 2 phospholipids can also desensitize neutrophils. Thus, cells incubated with either phosphocholine for 1 to 5 min in the absence of calcium and magnesium (which are required for aggregation) did not aggregate when exposed to the bivalent cations and fresh lipid stimulus. Also, cells incubated with either lipid for 5 min in the absence of cytochalasin B (which is required for degranulation) did not degranulate when exposed to cytochalasin B and fresh lipid stimulus. However, these desensitized neutrophils aggregated and degranulated fully in response to the chemotactic oligopeptide N-formyl-methionyl-leucylphenylalanine and C5a. In relation to the aggregation response, this selective desensitization was not due to lipid inactivation; it persisted after thorough cell washing; and it was not induced by a nonaggregating analogue, 1-O-alkyl-sn-glycerol-3-phosphocholine. Furthermore, cells desensitized to the formylated oligopeptide or C5a (by preincubation with either stimulus in the absence of bivalent cations) did not aggregate when challenged with the oligopeptide or C5a, respectively, but exhibited a normal or enhanced aggregation response to the 2 active phospholipids. These data support the concept that C5a, formylated oligopeptides, and phosphocholines represent 3 distinct classes of stimulants that activate and densensitize neutrophils by at least partially independent pathways. This activation and desensitization may be mediated by 3 types of cellular receptors, each of which interacts with only 1 class of stimuli.
Serologic and biochemical analyses of a variant Ae (E beta) ia polypeptide chain in D2.gD (H-2g2).
Authors: Lafuse W P , Hendrickson H I , Corser P S , David C S
Published: December 2022

Recombinant D2.Gd (KdAdBbJbEbCbSbDb) was derived from parental strains B6 (H-2b) and DBA/2 H-2d). Recent peptide studies and 2-D electrophoresis studies from other laboratories have shown that the Aed (E beta) chain of D2.GD is structurally different from the parental-derived chain. An antiserum (D2.GD X A. TFR5)F1 anti-DBA/2 was produced that detects an Ia specificity (Ia.50) in the I-E molecule formed by the parent Aed chain and lacking in the I-E molecule formed by the variant Aed. chain. The variant Ae chain could have derived either from a mutational event or an intracistronic cross-over.
Immune complexes in syphilis sera.
Authors: Wozniczko-Orlowska G , Milgrom F
Published: December 2022

Four hundred and forty-nine syphilis sera, positive in VDRL and FTA-ABS tests, were studied for the presence of circulating immune complexes (CIC) by means of anti-antibody (AA) neutralization test. Ninety-three (20.7%) sera had demonstrable CIC. Subsequently, dispersion of CIC by saline suspension of cardiolipin and by extract of rabbit testicular syphiloma was examined. Of 40 CIC-containing sera tested with cardiolipin, dispersion of CIC was noted in 16 instances; of 32 CIC-containing sera examined with syphiloma extract, dispersion was noted in 16 cases. Significantly, CIC that showed definite dispersion by cardiolipin were not dispersed by syphiloma extract and vice versa. Some studies were also performed on lepromatous leprosy and SLE. None of 27 cIC-containing lepromatous leprosy sera were affected by cardiolipin, but in 2 of 9 CIC-containing SLE sera, cardiolipin dispersed the complexes. Cardiolipin-anti-cardiolipin complexes that neutralized AA were frequently observed when cardiolipin was added to sera containing its corresponding antibodies but not CIC. Similar reactions were noted between the syphiloma extract and anti-treponemal antibodies.
LPS regulation of the immune response: suppression of immune responses to orally administered T-independent antigen.
Authors: Babb J L , Kiyono H , Michalek S M , McGhee J R
Published: December 2022

The regulation of immune responses to gastrically administered TI antigens has been investigated, and the characterization of a regulatory cell population has been performed. Intragastric administration of TNP-haptenated homologous erythrocytes (TNP-MRBC) induced splenic IgM anti-TNP PFC responses in LPS nonresponsive C3H/HeJ mice that were higher than those in LPS-responsive C3H/HeN mice and similar to those noted in athymic (nu/nu) C3H/HeN animals. The simultaneous intragastric administration of LPS with TNP-MRBC augmented immune responses in a manner similar to that previously reported for parenterally administered LPS and antigen. Further, LPS-induced augmentation of TNP-MRBC responses was greater in athymic mice. These findings were substantiated using in vitro spleen cultures. Intragastric challenge with a 2nd TI antigen, TNP-LPS, induced approximately 8-fold higher splenic anti-TNP PFC responses in athymic C3H/HeN mice compared with those in euthymic littermates. By admixture of B and T cell populations, it was demonstrated that the host responsiveness to TNP-LPS was negatively regulated by suppressor cells. Suppressive activity resided in a Thy 1.2-bearing, irradiation-resistant, nylon wool-nonadherent cell population. These cells could be demonstrated in spleen and Peyer's patches from young or old LPS-responsive C3H/HeN mice, but not in tissues from LPS nonresponsive C3H/HeJ mice. The specificity of the regulator cells was not limited to TNP-LPS responses, since immune responsiveness to another TI antigen, TNP-dextran, was also under the control of this cell population. These studies confirm the TI nature of TNP-MRBC and indicate that immune responses to gastrically administered antigens such as TNP-LPS, TNP-dextran, and possibly TNP-MRBC are negatively regulated by a suppressor T cell population. A role for endogenous LPS in the generation of regulator cells and the effect of these cells on host responses to gut-derived antigens is discussed.
Quantitative studies on concanavalin A-induced, TCGF-reactive T cells. I. Correlation between proliferation and lectin-dependent cytolytic activity.
Authors: Larsson E L , Lindahl K F , Langhorne J , Coutinho A
Published: December 2022

A limiting dilution assay was used to determine the frequencies of T cells that could be induced to proliferate and kill by Con A and TCGF. The frequency of proliferating cells was 1 in 5 nylon wool-purified spleen cells and 1 in 7 normal lymph node cells. The frequencies in the same cell populations of lectin-dependent killer cell precursors were 1 in 5 and 1 in 9, respectively. Even at limiting numbers of T cells seeded per culture, very few cultures proliferated without showing cytotoxic activity. Thus, under these conditions Con A and TCGF, preferentially if not exclusively, activate T cells that will kill in the presence of PHA. This experimental system can be used for estimating the repertoires of specific CTL-precursors activated by Con A and expanded in TCGF.
Determination of IgG subclasses and Gm allotypes in culture supernatants of pokeweed mitogen-stimulated human blood lymphocytes.
Authors: Morell A , Van Loghem E , Nef M , Theilkaes L , Skvaril F
Published: December 2022

Concentrations of the 4 IgG subclasses, of IgM, and of IgA were determined in culture supernatants of pokeweed mitogen-stimulated mononuclear cells isolated from human peripheral blood. Time-course studies showed cumulative secretion of IgM, IgA, and the subclasses IgG1, IgG2, and IgG3 but not of IgG4. In supernatants of 7-day cultures of unseparated mononuclear cells, IgG1 was predominant, followed by IgG2 and IgG3. Removal of most monocytes from the mononuclear cells resulted in an overall decrease of immunoglobulin production but had no influence on the relative IgG subclass distribution. In supernatants of T cell-enriched cultures, the synthesized IgG was deficient in IgG1. Likewise, in supernatants of B cell-enriched cultures, IgG2 exceeded IgG1 concentration. Elimination of the T gamma cells suggested some influence of this subset on IgG2 production. Gm allotypes determined in supernatants corresponded to those in serum of the blood donors.
Serologic and biochemical identification of minor histocompatibility (H-4) antigens.
Authors: Long P M , Lafuse W P , David C S
Published: December 2022

Mouse alloantiserum capable of detecting minor histocompatibility antigens has been produced. Cytotoxic antibody to products of the H-4 locus was produced by reciprocal immunization of minor H loci congenic strains B10 (H-4a) and B10.129(21M) (H-4b), with mitogen-stimulated lymphocytes and epidermal cells. Absorption studies suggested antibodies to more than 1 specificity. The antibodies cross-react with products of other minor H loci. Alloantiserum to the H-4 gene product precipitates a glycoprotein with a m.w. of approximately 45,000 from radiolabeled Con A-stimulated lymph node cells.
The relationship between surface immunoglobulin isotype and the immune function of murine B lymphocytes. V. High affinity secondary antibody responses are transferred by both IgD-positive and IgD-negative memory B cells.
Authors: Lafrenz D , Strober S , Vitetta E
Published: December 2022

We examined the adoptive secondary anti-DNP responses restored by surface IgD+ and IgD- memory B cells. Several parameters that might affect the affinity and magnitude of the adoptive responses were studied: 1) time after priming of cell donors, 2) source of anti-IgD antibodies used for immunofluorescent cell staining, 3) adjuvant used for priming, 4) carrier protein used for priming, 5) amount of antigen used for the challenge of adoptive hosts, and 6) the strain of ice used as donors and recipients. In contrast to previous reports, the present results demonstrate that the selection of cells with high affinity antigen receptors can occur to the same extent in both the delta + and delta - memory cell pools. This suggests that the loss of surface IgD is not a necessary intermediate stage in the maturation of memory B cells.
Acquisition of syngeneic I-A determinants by T cells proliferating in response to poly (Glu60Ala30Tyr10).
Authors: Nepom J T , Benacerraf B , Germain R N
Published: December 2022

The T cell proliferative response in mice to the synthetic polymer GAT is under Ir gene control, mapping to the I-A subregion of the H-2 major histocompatibility complex (MHC). Antigen-dependent proliferation in vitro of in vivo GAT-primed lymph node cells can be inhibited by a monoclonal antibody to Ia-17, an I-A public determinant. Using this antibody for direct immunofluorescent analysis, T cells in GAT-stimulated proliferative culture are identified that express syngeneic I-A during culture. This expression is strictly antigen dependent, requires restimulation in vitro, and requires the presence of I-A-positive adherent antigen-presenting cells. T cells bearing I-A can be enriched by a simple affinity procedure, and I-A-positive cells separated on a FACS are shown to retain antigen-specific reactivity. The acquisition of I-A determinants by T cells under these culture conditions is not nonspecific. The Ia determinants borne by T cell blasts appear to be dictated by the I subregion to which the relevant Ir gene maps, and which codes for the Ia molecule involved in presentation of the antigen. Thus, (B6A)F1 (H-2b X H-2a)F1 LNC express I-Ak antigens when proliferating to GAT but not when stimulated by GLPhe, the response to which is under I-E subregion control. The relation of Ir gene function to Ia-restricted antigen presentation and self-Ia recognition is discussed.
Photobleaching recovery studies of antigen-specific mouse lymphocyte stimulation by DNP-conjugated polymerized flagellin.
Authors: Peacock J S , Barisas B G
Published: December 2022

We have used fluorescence photobleaching recovery (FPR) to study the lateral diffusion of antigen-receptor complexes during stimulation of DNP-specific mouse B cells by the T-independent antigens DNP-polymerized flagellin (DNP-POL). Depending on epitope density and dose, these antigens behave either as immunogens or tolerogens. Lymphocyte DNP receptors binding DNP0.5 flagellin monomer show a diffusion constant D of 2.2 X 10(-10) cm2 sec-1 and ca 50% fluorescence recovery after bleaching. For DNP-POL bound to DNP-specific lymphocytes, the observed diffusion constants decrease monotonically with increased antigen dose and epitope density. Under optimally immunogenic conditions of DNP2.3-POL at 1 micrograms/ml, D = 1.5 X 10(-11) cm2 sec-1, some 14-fold less than for a single DNP receptor. Under tolerogenic conditions lower diffusion constants approaching 0.8 X 10(-11) cm-2 sec1 are observed. The fraction of aggregates mobile on the time scale of the experiment remains constant at about 50 to 60% in all immunogenic situations, but falls abruptly to about 24 to 32% in precisely those situations where the antigen/dose combination is tolerogenic. This might support the hypotheses that there exist critical epitope densities above which antigens and receptors form rigidly cross-linked aggregates that bring about B cell tolerance. The mobility of DNP0.5 flagellin monomer bound to receptors left unoccupied after treatment with various doses and batches of DNP-POL is independent of DNP-POL presence. Receptor aggregate diffusion is unaffected by treatment with colchicine or cytochalasin B.
Structural studies of a human gamma 3 myeloma protein (Goe) that binds staph protein A.
Authors: Recht B , Frangione B , Franklin E , van Loghem E
Published: December 2022

The partial amino acid sequence of the Fc region of an unusual monoclonal immunoglobulin molecule (Goe), which had the allotypic markers Gm (b0, b3, b5, s, t, v), rarely encountered in Caucasians, was determined. Protein Goe was previously shown to belong to the gamma 3 subclass by antigenic typing, to possess a gamma 3-like hinge region and a gamma 1-like carboxy-terminal octadecapeptide, and to bind to staphylococcal protein A. The sequence of protein Goe resembled that of gamma 3 molecules except for the presence of tyrosine at position 296, alanine at position 339, and histidine and tyrosine at positions 435 and 436. It is of interest that histidine 435 appears to play an important role in binding to Staph protein A. Since tyrosine and phenylalanine at 296 and 300 are typical of G3m(g) molecules, whereas protein Goe is G3m(g-), this may correspond to the non-b1 allotypic marker. Of the numerous explanations to account for these findings, the most likely possibilities are that protein Goe is either a hybrid molecule or the product of a germ line gene representing the G3m s allotype, which is rare in Caucasians and common in Mongoloid populations. Support for the latter alternative is provided by the isolation from normal serum of a small amount of a protein having many of the properties of protein Goe.
Immune reactive measles virus polypeptides on the cell's surface: turnover and relationship of the glycoproteins to each other and to HLA determinants.
Authors: Fujinami R S , Sissons J G , Oldstone M B
Published: December 2022

To better understand the mechanism(s) whereby antibody and complement and cytotoxic lymphocytes lyse infected cells, we studied the structure, interrelationship and turnover of measles virus polypeptides expressed on the cell's surface. Of the 6 major viral structural polypeptides, L, HA, P, NC, F, and M, found in purified virions or infected cells, only 2, the HA and F, resided on the surface of infected cells. The HA was present primarily in the form of a 160k dimer, and F was identified as a 64k polypeptide migrating distinct from other viral polypeptides. With reduction, the HA migrated as a 80k monomer, and F0, after cleavage, was found to be composed of a 42k nonglycosylated polypeptide, F1, and a 24k glycosylated protein, F2. The relationship between F0 and F1 and between the HA dimer and monomer was verified by tryptic peptide mapping. The turnover of HA and F from the cell's surface was 10 and 9 hr, respectively. However, in the presence of specific antibody after a marked loss of viral antigen from the surface, the turnover for HA and F was 15 and 12 hr, respectively. Despite being independent molecules, HA and F were closely linked, as they moved together (co-capped) over the plasma membrane when incubated with monospecific or monoclonal antibody. In contrast, neither HA nor F co-capped with the major histocompatibility antigens or with other host cell proteins, which indicates a separation between these host cell proteins and measles viral glycoproteins on the cell's surface.
In vitro antigen-mediated clonal expansion of memory B lymphocytes.
Authors: Brooks K H , Feldbush T L
Published: December 2022

An in vitro model for the propagation and expansion of the memory B lymphocyte population is described. DNP-BGG immune cells were mixed with OVA immune cells and challenged immediately with DNP-OVA. After the 1st response had begun to wane, the cells were rechallenged with DNP-OVA (day 11 of culture). An average of 13-fold more PFC were observed after delayed challenge (day 11). This expansion in the PFC response was an antigen-dependent process and did not involve recruitment of new memory cells from the virgin lymphocyte pool. The level of expansion of the memory cell pool was also calculated using limiting dilution analysis and was found to fall in a range of 16- to 67-fold increase in precursor frequency. In addition to the expansion of the memory B cell population, we also observed the development of 2 immunoregulatory cycles previously observed only in vivo. First, in the presence of persistent antigen, a cyclical PFC response was seen. Second, after day 10 of culture, optimal PFC numbers were observed only when DNP-lysine was added to the plaque assay. Such hapten-augmentable PFC responses have been reported by other investigators as indicative of anti-idiotypic regulation. This possibility is examined more extensively in the following communication.
A monoclonal antibody inhibiting human neutrophil chemotaxis and degranulation.
Authors: Cotter T G , Spears P , Henson P M
Published: December 2022

The hybridoma technique of Kohler and Milstein was used to raise a monoclonal antibody against human neutrophils it has been found to inhibit neutrophil chemotaxis and degranulation. The antibody has been termed NCD 1. Incubation of 12 micrograms of NCD 1 with neutrophils (2 X 10(6)), followed by incubation with cytochalasin B and stimulation with either C5a, fMet-Leu-Phe, or soluble aggregated immunoglobulin, resulted in the inhibition of lysosomal enzyme release. The inhibition was not cytochalasin B dependent, since lysosomal enzyme release induced by opsonized zymosan or opsonized sheep erythrocytes was also inhibited, even in the absence of cytochalasin B. NCD 1 had no affect on enzyme release induced by the calcium ionophore A23138 or by phorbol myristate acetate. The antibody also inhibited neutrophil chemotaxis to zymosan-activated plasma and fMet-Leu-Phe. By contrast, superoxide production stimulated by phorbol myristate acetate, opsonized zymosan, or fMet-Leu-Phe was not affected by NCD 1. Similarly, uptake of 51Cr-labeled opsonized sheep erythrocytes into neutrophils was resistant to the effects of the antibody. NCD 1 Fab fragments did not inhibit lysosomal enzyme release or chemotaxis, althugh binding to the neutrophil surface was demonstrated by immunofluorescence. NCD 1 F(ab')2 fragments behaved analogously to the whole antibody. Binding of both fMet-Leu-[3H]Phe or 125I-soluble aggregated immunoglobulin to the cells was not inhibited by the antibody, which implied that NCD 1 was inhibiting some post-ligand binding event.
Phagocytosis and killing of the protozoan Leishmania donovani by human polymorphonuclear leukocytes.
Authors: Pearson R D , Steigbigel R T
Published: December 2022

The role of polymorphonuclear leukocytes (PMN) in host defense against Leishmania donovani, the protozoan that causes visceral leishmaniasis, is unknown. To assess the ability of PMN to ingest and kill the infecting promastigote stage of the organism, cytocentrifuge preparations were made from tumbled suspensions of 5 X 10(6) PMN, an equal number of promastigotes, and fresh human serum deficient in the 6th component of complement. 53 +/- 9% PMN were found to have 1 or more associated promastigotes, and 81 +/- 14 promastigotes were found per 100 PMN after 15 min at 37 degrees C. There was a corresponding decrease in extracellular promastigotes from 5 x 10(6) ml to 2.7 X 10(4)/ml. Superoxide anion was generated during phagocytosis. Ingetion was saturable with respect to promastigote concentration, required heat labile factors, and was minimal when suspensions were incubated in ice water. Intracellular killing of promastigotes was indicated by a decline in cell-associated organisms without a concomitant increase in extracellular promastigotes. Light and electron microscopy showed disintegration of intracellular promastigotes. Oxidative killing mechanisms appear to be required for PMN killing of this protozoan organism, since there was no decline in intracellular organisms in PMN from a donor with chronic granulomatous disease. Promastigotes studied in a phagocyte-free system were susceptible to H2O2 generated from glucose by glucose oxidase or added directly at greater than or equal to 10(-5) M. Killing was enhanced by the addition of lactoperoxidase (50 mU/ml) with KI (0.05 mM) and inhibited by fresh, but not boiled catalase in the glucose-glucose oxidase system. These studies demonstrate that human PMN can ingest and kill L. donovani by the H2O2-peroxidase-halide system and may be capable of providing host defense against the invading, promastigote stage of this pathogen.
Transmethylation reactions are required for initial morphologic and biochemical responses of human monocytes to chemoattractants.
Authors: Pike M C , Snyderman R
Published: December 2022

Transmethylation reactions mediated by S-adenosyl-L-methionine are required for the chemotaxis of mononuclear leukocytes. It is not yet known, however, whether methylation reactions participate in the initial transduction of the chemotactic signals that lead to the alterations in cellular morphology required for chemotaxis and/or whether they are necessary for the subsequent biochemical events needed for sustained directed migration. We therefore investigated the effects of inhibiting methylation on 2 early responses induced by chemoattractant-receptor occupancy in human monocytes; the rapid morphologic alteration from round to a triangular, motile cell configuration (polarization) and the release of [3H]-arachidonic acid from membrane phospholipids. Both of these initial responses to 3 types of chemoattractants were severely depressed in monocytes treated with the methylation inhibitors, erythro-9-[2-hydroxy-3-nonyl]adenine (EHNA) plus adenosine and L-homocysteine or by 3-deazaadenosine plus L-homocysteine. These findings indicate that methylation reactions are required for the transduction of signals after chemotactic factor receptor occupancy in monocytes, which lead to a motile cellular configuration and release of arachidonic acid from membrane phospholipids. Activation of phospholipases with destruction of cell-associated phosphatidylinositol appears to account for the major source of arachidonic acid released by monocytes exposed to chemoattractants. This pathway for arachidonic acid release requires a transmethylation reaction since it is blocked by inhibitors of methylation.
An 8th rabbit b allotype (b92) detected by a genetic study.
Authors: Benammar A , Cazenave P A
Published: December 2022

Genetic study of the progeny of a Spanish wild rabbit has revealed 2 unknown allotypic specificities that behave as encoded by alleles at the b locus. One of these A92 is described in this paper. This specificity is located on immunoglobulin light chains and cross-reacts with anti-b4 and presumably with anti-b9 sera. These data indicate that A92 is a "new" allotype of the b series and is thus designated b92.
Absorption of normal lymphocytes on allogeneic spleen monolayers: depletion of alloreactivity is due to inhibition of CTL induction by released monolayer cells.
Authors: Kelso A
Published: December 2022

A technique for the haplotype-specific depletion of precursors of alloreactive cytolytic T lymphocytes (CTL-P) by absorption of unprimed spleen cells on allogeneic lymphocyte monolayers has been examined. When H-2d spleen cells were incubated on monolayers of H-2b spleen cells and the nonadherent cells were cultured in mixed leukocyte culture (MLC), CTL activity generated against the monolayer haplotype was 30- to 1000-fold lower than the equivalent cultures of unabsorbed H-2d cells. Cytolytic reactvity to a 3rd-party haplotype, H-2k, was reduced no more than 6-fold. However, culture of the same cells at limiting dilution indicated that the frequency of CTL-P against the monolayer haplotype in monolayer-nonadherent H-2d populations was not significantly different from the frequency in normal H-2d spleen. It was noted that MLC of monolayer-nonadherent H-2d populations were highly cytolytic for H-2d target cells. This reaction was reduced and the ability to generate anti-H-2b CTL was restored when the nonadherent cells were treated with anti-H-2b antibody and complement to eliminate contaminating monolayer cells released during absorption, and when monolayers were prepared from spleen cells depleted of Lyt 2-bearing cells (and hence CTL-P). These data suggested that the reduction in anti-H-2b reactivity of monolayer-nonadherent cells in MLC was due to inhibition by the competing anti-H-2d reaction of contaminating, monolayer-derived CTL-P. Although fluorescent labeling of monolayer cells indicated that these cells represented only 10% of the nonadherent population, flow cytometry and further limiting dilution analysis demonstrated that cells that detached from H-2b monolayers during absorption were enriched 2-fold in T lymphocytes and CTL-P over normal spleen. The strength of the anti-H-2d reaction by a minority of monolayer cells can thus be attributed both to the higher frequency of H-2b anti-H-2d than H-2d anti-H-2b CTL-P in spleen populations and to the preferential detachment of monolayer T lymphocytes during absorption.
kappa/lambda Shifts do not occur during maturation of murine B cells.
Authors: McGuire K L , Vitetta E S
Published: December 2022

We have used highly specific affinity-purified antibodies against mouse kappa- and lambda chains in conjunction with both immunofluorescence analysis on the FACS and enzymatic radioiodination of murine splenocytes and bone marrow cells. Our results indicate that the kappa/lambda ratio of cell surface immunoglobulin is constant during the ontogenetic development of B cells, i.e., a shift in the kappa/lambda ratio does not occur during B cell maturation. Our results suggest that the events controlling kappa and lambda expression on murine B cells are decided very early in ontogeny, before significant antigenic selection.
Host modification of Sindbis virus sialic acid content influences alternative complement pathway activation and virus clearance.
Authors: Hirsch R L , Griffin D E , Winkelstein J A
Published: December 2022

Previous studies have shown that Sindbis virus, an enveloped alphavirus of the togavirus group, activates the alternative complement pathway in the absence of detectable antiviral immunoglobulin. The present studies examined the role of the host-determined sialic acid content of Sindbis virus on activation of the alternative complement pathway. Purified Sindbis virus grown in baby hamster kidney (BHK-SV) and in mosquito (MOSQ-SV) cells yielded virus with 10.2 and less than 2.0 nmol sialic acid/mg viral protein, respectively. Sindbis virus deficient in sialic acid (2.0 nmol sialic/mg) was also produced by treating the BHK-SV with neuraminidase (NANase-SV). When MOSQ-SV or NANase-SV was incubated in either C4DGPS or C2DHS, each consumed significantly more C3 than did BHK-SV, indicating that the ability of Sindbis virus to activate the alternative pathway is inversely related to its sialic acid content. Studies in vivo showed that virus deficient in sialic acid (MOSQ-SV) was cleared from the blood of mice much more efficiently than was virus rich in sialic acid (BHK-SV), after i.v. inoculation. Furthermore, when animals were depleted of C3 through C9 by cobra venom factor (CoVF) treatment, no differences in the clearance of high and low sialic acid-containing viruses were observed. Thus both the activation in vitro and complement-dependent clearance in vivo are significantly affected by the host-determined sialic acid content of Sindbis virus.
The binding of BCG-activated macrophages to tumor targets stimulates secretion of cytolytic factor.
Authors: Johnson W J , Whisnant C C , Adams D O
Published: December 2022

The binding of neoplastic targets and the secretion of a potent cytolytic protease (CF) by BCG-activated macrophages have previously been shown to be independent functions, both of which are necessary for completion of macrophage-mediated cytolysis. The present studies demonstrate that secretion of CF is triggered by the binding of neoplastic targets to BCG-activated macrophages. The binding of tumor targets, but not of normal lymphocytes, resulted in enhanced secretion of CF from BCG-activated macrophages, although not from macrophages elicited by thioglycolate broth. Dead or metabolically inactive tumor targets, as well as membrane preparations of tumor targets, induced secretion of CF from BCG-activated macrophages. The blocking of macrophage-target binding with a porous filter prevented augmented secretion of CF. Appreciable secretion of CF occurred in as little as 30 min after addition of tumor targets to BCG macrophages. Binding did not induce a generalized increase in secretion of neutral proteases by BCG macrophages, since secretion of plasminogen activator was actually decreased after the binding of P815 targets. The data suggest the selective binding of BCG-activated murine macrophages to neoplastic targets triggers the secretion of a potent CF.
Natural killer activity in the peritoneal exudates of mice infected with Listeria monocytogenes: characterization of the natural killer cells by using a monoclonal rat anti-murine macrophage antibody (M1/70).
Authors: Holmberg L A , Springer T A , Ault K A
Published: December 2022

Exudates induced by i.p. injection of five listeria monocytogenes (LM) constituted a rich source of CBA/J murine natural killer (NK) cells. Maximum expression of NK activity was seen from day 2 through day 6 after initial exposure to LM. When nylon wool nonadherent peritoneal exudate cells were examined by a single-cell cytotoxicity assay, the number of cells binding to YAC-1 target cells increased after infection as did their individual lytic capacity. A monoclonal rat anti-murine macrophage antibody (M1/70), previously shown by our group to recognize human NK cells, can also be used as a marker for murine NK cells. Utilizing M1/70 and the fluorescence-activated cell sorter, selection of M1/70-labeled mononuclear cells led to the enrichment of both NK and antibody-dependent cellular cytotoxicity. These M1/70-positive cells had a distinctive morphology and contained granules on Wright-Giemsa staining. They were not phagocytic, did not contain nonspecific esterase, and lacked surface I-Ak, IgM determinants, complement receptors, and high levels of Thy 1.2.
Parallel cross-reactivity patterns of 2 sets of antigenically distinct cytochrome c peptides: possible evidence for a presentational model of Ir gene function.
Authors: Hansburg D , Hannum C , Inman J K , Appella E , Margoliash E , Schwartz R H
Published: December 2022

B10.A mice were immunized with either the carboxyl terminal peptide fragment 81-104 of pigeon cytochrome c or its acetimidyl derivative and an immune response was seen with strong preference for the immunogen. Strain distribution studies and blocking with an anti-Ia monoclonal antibody indicated that the same immune response (Ir) gene and restriction element were utilized in both responses. The specificity of the responses were evaluated by restimulating in vitro with a set of cytochrome c fragments from various species. Even though the derivatized and native fragments were poorly cross-reactive, the same phylogenetic pattern was seen when pigeon cytochrome c fragment 81-104 primed cells were tested with the set of underivatized fragments and when acetimidyl pigeon cytochrome c fragment 81-104 primed cells were tested with the same set of derivatized fragments. Primed cells from a 2nd major histocompatibility complex congenic strain of mice, B10.A(5R), displayed equivalent discrimination between derivatized and native forms but showed a markedly different phylogenetic pattern of cross-reactivity. These data indicate that the immune system recognizes 2 sites on the nominal antigen. One site, which accounts for the common hierarchy and is under Ir gene control, contains residues Gln-100, and possibly other carboxyl terminal residues. The 2nd site, which effects the distinction between native and derivatized fragments, contains at least 1 lysine other than at the carboxyl terminal. The implications of these data for theories of T cell recognition and Ir gene function are discussed.
Substrate hydrolysis by immune complex-activated neutrophils: effect of physical presentation of complexes and protease inhibitors.
Authors: Johnson K J , Varani J
Published: December 2022

The ability of rat leukocytes to hydrolyze a radiolabeled, surface-bound protein substrate in a solid phase assay was determined, and various factors that influence the process were measured. Unstimulated leukocytes hydrolyzed very little substrate. When the cell suspension was mixed with zymosan particles or incubated with preformed immune complexes, the amount of substrate hydrolysis increased dramatically. Not surprisingly, immune complexes at equivalence proved to be the most effective in eliciting the response. Immune complexes attached to the surface along with the protein substrate were able to effectively induce hydrolysis, though they were not as effective as immune complexes in suspension. Three protease inhibitors, alpha 1-antitrypsin, alpha 2-macroglobulin, and soybean trypsin inhibitor, which were able to neutralize nearly all of the protease activity in rat neutrophil lysates, were tested for their ability to inhibit immune complex-induced protein hydrolysis. It was found that when the inhibitors were surface bound along with the substrate protein, they were effective in preventing the neutrophils from hydrolyzing the protein. However, when the same inhibitors were present in the fluid phase, they were much less effective. The relative ineffectiveness of fluid phase protease inhibitors to block the protease activity of contact-activated leukocytes may explain how immune complex injury can take place in the presence of high concentrations of serum inhibitors.
In vitro production of anti-influenza virus antibody after intranasal inoculation with cold-adapted influenza virus.
Authors: Yarchoan R , Murphy B R , Strober W , Clements M L , Nelson D L
Published: December 2022

We have studied the production of anti-influenza virus antibody in vitro by peripheral blood mononuclear cells (PBMC) obtained from 7 normal volunteers at various times after intranasal inoculation with cold-adapted A/Alaska/6/77 [H3N2] influenza virus. Antibody released into culture supernatants was assayed by a 2-step enzyme-linked immunosorbent assay (ELISA). Cells obtained 6 days after intranasal inoculation spontaneously released both IgG and IgA anti-influenza antibody; this antibody production occurred within 24 hr, was specific for the virus used to inoculate the volunteers, and was inhibitable by cycloheximide. When day 6 cells were cultured in vitro for 12 days with the polyclonal activator pokeweed mitogen (PWM), no increase in the amount of antibody above that released in the absence of PWM was seen. In contrast, cells obtained 27 days after inoculation made no spontaneous antibody. In addition, cultures of these day 27 cells with PWM resulted in the production of large amounts of IgG antibody but relatively little IgA anti-virus antibody. Thus, after a mucosal influenza virus infection, several subpopulations of functionally different cells sequentially appear in the peripheral circulation: an initial population of cells secreting IgG and IgA antibody spontaneously, followed by a 2nd population of cells secreting IgG antibody when stimulated with PWM.
Biologic properties of chromatographically separated murine thymoma-derived Interleukin 2 and colony-stimulating factor.
Authors: Hilfiker M L , Moore R N , Farrar J J
Published: December 2022

Two growth factors, interleukin 2 (T cell growth factor) and colony-stimulating factor, are produced concomitantly by a murine EL-4 thymoma cell line after stimulation by phorbol myristate acetate. As shown elsewhere, these thymoma-derived factors appear to be biochemically and functionally indistinguishable from the interleukin 2 and colony-stimulating factor produced by mitogen-stimulated mouse spleen cells. Both factors co-elute during gel filtration with apparent m.w. in the range of 30,000, and both exhibit overlapping isoelectric point profiles between pH 4 and pH 5. Because we were unable to separate these 2 factors by methods based on either m.w. or charge, we have used phenyl-Sepharose chromatography, a method based on hydrophobic interactions, to completely separate murine interleukin 2 and colony-stimulating factor. In contrast with published reports, each of the separated factors exhibits unique biologic activities on lymphocytes and macrophages. Interleukin 2 provides help for antibody synthesis in the nude mouse, but neither enhances interferon production by macrophages nor stimulates macrophage growth. Colony-stimulating factor does not enhance antibody synthesis in the nude mouse but does enhance interferon production by macrophages and stimulate macrophage growth.
Suppression of experimental allergic encephalomyelitis in guinea/pigs by liposome-associated human myelin basic protein.
Authors: Strejan G H , Percy D H , St Louis J , Surlan D , Paty D W
Published: December 2022

Human myelin basic protein (MBP) was inserted into phosphatidyl-serine liposomes and Hartley guinea pigs were treated with 1 or 2 injections of MBP-liposomes mixture by the intracardial route before an encephalitogenic challenge with MBP in CFA. Other groups of guinea pigs were pretreated with equivalent amounts of MBP in saline or of MBP in IFA. Of 24 untreated animals, 22 developed EAE and died or had to be sacrificed within 15 days after challenge. Only 4 of 29 guinea pigs treated with either 75 microgram or 112 microgram MBP-liposomes developed clinical signs of the disease. In the group pretreated with MBP in saline, 11 of 15 animals died, whereas in the MBP-IFA group, only 4 out of 10 died. Histologic modifications were also decreased in the MBP-liposomes and MBP-IFA groups, but in many instances, clinical normal guinea pigs showed disseminated perivascular infiltrates in the brain and spinal cord. Delayed hypersensitivity reactions to MBP were positive in all but 1 animal tested. Early T-rosette levels followed essentially the clinical course of the disease: they were drastically decreased 7 days after challenge in the untreated and MBP-saline-treated groups, but remained essentially normal in the MBP-liposomes group throughout the experiment. Lymphocyte transformation tests carried out in parallel with soluble MBP and with MBP-liposomes indicated that animals in certain groups responded preferentially to 1 form or the other of the antigen. Compared with prevailing procedures, the single i.v. injection of a relatively small amount of liposome-associated MBP appears to represent a promising approach for the antigen-specific suppression of EAE.
Activation of human T lymphocyte subsets: helper and suppressor/cytotoxic T cells recognize and respond to distinct histocompatibility antigens.
Authors: Engleman E G , Benike C J , Grumet F C , Evans R L
Published: December 2022

This study was directed at determining the major histocompatibility complex (MHC) antigens recognized by helper (Leu-3) and suppressor-cytotoxic (Leu-2) T lymphocyte subsets in man. These 2 subsets were isolated from peripheral blood with monoclonal antibodies and challenged in vitro with various stimuli. Only Leu-3 cells proliferated in response to autologous nonrosetting cells and soluble antigens, suggesting that helper but not suppressor-cytotoxic T cells recognize autologous HLA-DR antigen. Furthermore, only Leu-3 T cells responded to allogeneic DR antigen; this was shown in reactions between 2 siblings who were HLA-identical except for a single disparity at HLA-DR caused by a crossover event. Leu-3 cells activated in primary allogeneic mixed leukocyte reactions (MLR) responded equally in secondary allogeneic MLR to the priming cells and to cells that were identical at HLA-DR but discordant at HLA-A, B, and C to the priming cell. The antigens responsible for stimulating Leu-2 cells in allogeneic MLR were not identified, although the results are compatible with a role for HLA-A and B antigens and exclude a dominant role for HLA-DR. These data indicate that the helper and suppressor-cytotoxic T cell subsets in man respond differentially to MHC antigens in a manner analogous to the murine Lyt-2- 3- and Lyt-2+ 3+ populations.