Interactions between molecules (subfactors) released by different T cell sets that yield a complete factor with biological (suppressive) activity.

T cells that have been immunized to express optimal levels of contact hypersensitivity upon adoptive transfer to normal animals can be inhibited from doing so by incubating them with an antigen-specific T suppressor factor. This factor is composed of at least two subunits which come from cells expressing different Ly phenotypes; an antigen-specific antigen-binding "subfactor" is made by an Ly-1 cell and a non-antigen-binding one is made by an Ly-2 cell. Neither of these cells nor their products express detectable amounts of major histocompatibility gene products.

Transfer of an antigen-specific immediate hypersensitivity-like reaction with an antigen-binding factor produced by T cells.

The fact that T cell-dependent activation of mast cells occurs in delayed-type hypersensitivity led us to investigate whether a T cell product could mimic some of the functions of IgE. We report that 24- or 48-hr cultures of T cells from mice immunized optimally for delayed-type hypersensitivity resulted in release of an antigen-binding factor that transferred the ability to elicit an antigen-specific immediate hypersensitivity-like skin reaction in normal recipients. The responsible factor was concentrated and purified by affinity chromatography on antigen columns and was distinguished from immunoglobulin by several criteria: (i) it was released by purified T cells (anti-immunoglobulin plate depletion of B cells); (ii) it expressed no known antigenic markers of immunoglobulins (enzyme-linked immunosorbant direct binding assay); (iii) it had a molecular weight of 70,000 or less (sucrose gradient ultracentrifugation); and (iv) it had serological markers associated with antigen-specific T cell factors from other experimental systems.

Detection of T cells that secrete molecules which share determinants with antigen-specific T-cell factors.

A single-cell secretion assay was used to detect cells that secrete products which react with an antiserum that binds T cell antigen-binding polypeptides. The antiserum (R11), which was produced by immunization of rabbits with a murine trinitrophenyl-specific suppressor factor, reacts with T cells and their products and with a suppressor T-cell clone but not with B cells or their products. The secretory cells this antiserum detected were found to be unevenly distributed among various organs (spleen, lymph node, and thymus) and, to different degrees, in spleens of various strains of mice.

Expression of an idiotype (Id-460) during in vivo anti-dinitrophenyl antibody responses. II. Transient idiotypic dominance.

After immunization of mice with 2,4-dinitrophenyl-ovalbumin (DNP-OVA), it was shown previously that strains having Igh-Va genes and able to express light chains of the Vk1 group produce high levels of anti-DNP antibody bearing an idiotype (Id-460) associated with the combining site of the BALB/c DNP-binding myeloma protein MOPC 460. Expression of Id-460 in serum is transient; Id-460 levels peak early in the response and are regulated independently of total anti-DNP antibody. In this paper, the transient dominance of Id-460 expression has been confirmed at the cellular level by inhibition of splenic anti-DNP plaque-forming cells (PFC) with rabbit anti-Id-460 antiserum.

Characterization of T-cell surface proteins bound by heterologous antisera to antigen-specific T-cell products.

Heterologous antisera specific for murine T-cell antigen-recognition molecules were prepared by immunization of rabbits with dinitrophenyl-specific murine T-cell suppressor factors that had been purified by hapten-affinity chromatography. The antisera (i) bind to antigen-specific T-cell products that differ in their antigen-recognizing specificity; (ii) absorb the specific suppressor activity in preparations containing suppressor factors; (iii) stain all Lyt2+ T cells brightly in indirect immunofluorescence examination, stain some Lyt1+ cells (with low intensity), and do not stain B cells; (iv) precipitate cell membrane proteins from T cells that bear striking structural resemblance to the antigen-specific molecules used for immunization. These results suggest that, like B cells, there is a commonality between antigen-specific effector molecules released by T cells and their membrane-associated receptors.

Isolation and partial characterization of an antigen-specific T-cell factor associated with the suppression of delayed type hypersensitivity.

Antigen-specific factors associated with immunosuppressive activity, released by cultured T cells from mice tolerant to the haptens trinitrophenyl, dinitrophenyl and oxazolone, were purified by hapten affinity chromatography. Their binding specificity for antigens paralleled their immunoregulatory activity. Like some immunoglobulin molecules, these factors had blocked NH2 termini and could be bound to Fc-like receptors on macrophages.

Quantitation of human platelet transformation on siliconized glass: comparison of "normal' and "abnormal' platelets.

A series of typical morphological stages, representing progression of transformation, may be defined following adhesion of platelets to a siliconized glass surface. Platelets are visualized by new light microscopic techniques that allow quantitative categorization of transformation of large platelet populations by morphological stage, and thus the detection and elucidation of platelet defects which influence transformation. Living platelets form each of five subjects with bleeding disorders, due to platelet defects, exhibited a pattern of morphologic transformation which differed from normal.

Expression of an idiotype (Id-460) during in vivo anti-dinitrophenyl antibody responses. I. Mapping of genes for Id-460 expression to the variable region of immunoglobulin heavy-chain locus and to the variable region of immunoglobulin kappa-light-chain locus.

The genetic contro of the expression of an idiotype (Id-460) associated with the 2,4-dinitrophenyl (DNP)-binding BALB/c myeloma protein MOPC 460 was studied using congenic strains of mice. It was shown that the expression of high levels of Id-460 during secondary in vivo anti-DNP-ovalbumin responses was determined by genes governing immunoglobulin heavy-chain variable and kappa-light chain variable regions (V kappa). Appropriate alleles at both loci were required for the expression of Id-460.

pH, PCO2 and PO2 in "high-volume" platelet concentrates prepared by discontinuous-flow centrifugation and stored in polyvinylchloride and plyethylene containers.

High-volume (200 ml) platelet concentrates prepared by discontinuous-flow centrifugation, with counts as high as ca. 2.0 x 10(12)/l, were stored in either 600 ml-capacity polyvinylchloride bags or 800-ml capacity polyethylene bags.

Transformation and motility of human platelets: details of the shape change and release reaction observed by optical and electron microscopy.

Blood platelets from 10 normal human subjects have been examined with a sensitive differential interference contrast (DIC) microscope. The entire transformation process during adhesion to glass is clearly visible and has been recorded cinematographically, including the disk to sphere change of shape, the formation of sessile protuberances, the extension and retraction of pseudopodia, and the spreading, ruffling, and occasional regression of the hyalomere. The exocytosis of intact dense bodies can be observed either by DIC microscopy, or by epifluorescence microscopy in platelets stained with mepacrine.

Reduction of salivary tissue factor (thromboplastin) activity by warfarin therapy.

The coagulant of normal human saliva has been identified as tissue factor (thromboplastin, TF) by virtue of its ability to cause rapid coagulation in plasmas deficient in first-stage coagulation factors and to activate factor x in the presence of factor VII and by virtue of the fact that its activity is expressed only in the presence of factor VII and is inhibited by an antibody to TF. The TF is related to cells and cell fragments in saliva. Salivary TF activity has been found to be significantly reduced in patients taking warfarin.

Standardization of the one-stage assay for factor VIII (antihemophilic factor).

Although considerable progress has been made in perfecting the one-stage assay for factor VIII (antihemophilic factor), there remain variables that influence test results within laboratories as well as reproducibility between laboratories which have not been adequately evaluated. The purpose of this paper is to elucidate certain aspects of this assay that have not received adequate consideration and to describe the authors' assay method in order to provide a basis for comparison with results from other laboratories. It appears that variability results from: (1) differences in coagulability of different batches of substrate plasma obtained at different times from the same individual; (2) instability of some batches of stored substrate or standard plasmas; (3) variation in coagulability among vials of stored substrate or standard plasma from the same batch; (4) variation due to non-plasma reagents and instrumentation used to execute the test.

Gamma heavy chain disease seen initially as gastric neoplasm.

A patient with abdominal pain, weight loss, and a gastric mass was found to have a pleomorphic infiltrate of lymphocytes and plasma cells. Analysis of serum proteins revealed gamma heavy chains, which were detected in the urine as well. This case is unusual because of the extralymphatic involvement and the possibly unique character of the heavy chain, an insertion in added polypeptides.

A newly described activity of guinea pig IgG1 antibodies: transfer of cutaneous basophil reactions.

Hapten-specific delayed time course skin reactions containing predominant accumulations of basophils and eosinophils were elicited in newborn guinea pigs after i.v. transfer of small amounts of oxazolone immune serum.

Effect of temperature on short-term preservation of platelets for in vitro tests.

We have evaluated the effect on the response of citrated platelet-rich plasma to aggregating agents of storage at 4 degrees C versus room temperature (21 degrees C) for 2 and 4 h after venipuncture. While there were small decreases in some responses to epinephrine, ADP and collagen attributable to 21 degrees C storage, only in the case of ristocetin-induced aggregation was a profound difference noted. Platelets stored at 4 degrees C for 4 h showed no significant change in response to ristocetin.