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Kinetic studies are used to investigate metabolic processes. By adding an isotope to a system and measuring its movement in the system over time, pool sizes and transport rates can be determined by mathematically modeling the data. This approach enables rate differences to be determined in conditions that have been modified by diet, environment, genetics or disease. Kinetic studies in humans have shown that there are multiple pools of zinc that turnover from minutes to years and that processes, including zinc absorption and excretion, are regulated to maintain tissue levels when zinc intake varies. Animal studies allow for greater understanding of kinetics because more tissues can be sampled and environmental and genetic factors can be controlled. Kinetic studies in animals will provide information on the overexpression or the deletion of genes coding for specific proteins involved in zinc transport and metabolism. The advances that have been made in our understanding of the role of zinc in metabolism have been aided by the development of techniques for measuring isotopes in biological materials. In the future, the kinetics of zinc bound to different compounds will be measured. Modeling will enable this information, at the molecular level, to be integrated with knowledge of zinc metabolism at the cellular, organ and whole body level. To understand more fully the role of zinc in human health, kinetic studies are needed in healthy and disease states to identify differences in metabolic processes. This knowledge can be used as a basis for dietary and therapeutic recommendations.

Zinc (Zn) is an essential nutrient for growth, but little is known about Zn absorption, distribution, excretion, and retention in preterm infants. Nine infants with gestational age 32+/-1 wk (mean+/-SE), birth weight 1.44+/-0.08 kg, postnatal age 14+/-3 d, on Zn intake of 23+/-3 micromol/kg per d via enteral feeding of preterm formula were studied. A stable Zn isotope (70Zn) was administered orally or i.v., and plasma, red blood cells, urine, and feces were sampled for up to 30 d. Samples were analyzed for Zn by inductively coupled plasma atomic emission spectrometry and for isotope enrichment by inductively coupled plasma mass spectrometry. Data were analyzed by compartmental analysis using the Simulation Analysis and Modeling program, and absorption, distribution, excretion, and retention were calculated. Absorption was 36+/-5% or 7+/-1 micromol/kg per d; distribution in plasma was 15+/-1 micromol Zn/L and in RBC was 41+/-4 micromol Zn/L; excretion in urine was 0.55+/-0.03 micromol Zn/kg per d and in feces was 17+/-3 micromol Zn/kg per d and retention was 5+/-1 microl/kg per d. Results show that healthy preterm infants with Zn intake of 23 micromol/kg per d and expected growth rates (> 15 g/kg per d) absorb and retain Zn at rates comparable to in utero accretion. The values for absorption, distribution, and excretion by this population of healthy preterm infants provide a normal range for future studies, although further studies are required to determine endogenous excretion rates in healthy preterm infants. We speculate that these values can be used to determine whether Zn kinetics are abnormal in sick infants or in infants with slow growth.

Aim: To measure circulating antibodies to yeast organisms that could be used to characterise the yeast specific immune response in gastrointestinal disease., Methods: A quantitative, isotype specific enzyme linked immunosorbent assay was developed to measure circulating antibodies to an aqueous extract of Saccharomyces cerevisiae (sacc). Comparisons of specific antibody concentrations were made between 224 healthy controls and 51 patients with Crohn's disease, 41 with ulcerative colitis, 24 with indeterminate colitis, 23 with chronic liver disease, 17 with coeliac disease, and seven with irritable bowel syndrome. Additional comparisons were made between Crohn's disease and ulcerative colitis patients. Within the Crohn's disease group, the dependence of antibody levels on several clinical variables was assessed., Results: IgG and IgA anti-sacc antibodies were significantly raised in Crohn's disease. IgG antibodies were also raised in patients with chronic liver disease. Among patients with Crohn's disease, IgG antibody concentrations were higher in those with serum alpha 1 acid glycoprotein (AAG) above the normal range and there was a strong trend towards increased IgG anti-sacc in the presence of small bowel disease, whereas IgA anti-sacc correlated positively with disease duration. No differences were detected according to whether patients were taking steroids. Neither the Crohn's disease nor the chronic liver disease group differed from normal subjects in respect of IgG antibodies to bovine milk casein. On linear regression analysis of complete data from 39 Crohn's disease patients, AAG was found to be a significant predictor of both IgG and IgA antibodies, and male sex and disease duration to be additional predictors of IgA antibodies. There was a significant difference in IgG antibodies between Crohn's disease and ulcerative colitis., Conclusions: Raised antibodies to yeast, although not completely specific for Crohn's disease, may have a future role in diagnosis. The assays described here could be used to address this question in the context of a prospective study.

We studied 32 helicopter pilots before, during, and after 4-5 d trips from Aberdeen, Scotland, to service North Sea oil rigs. On duty days, subjects awoke 1.5 h earlier than pretrip or posttrip, after having slept nearly an hour less. Subjective fatigue was greater posttrip than pretrip. By the end of trip days, fatigue was greater and mood more negative than by the end of pretrip days. During trips, daily caffeine consumption increased 42%, reports of headache doubled, reports of back pain increased 12-fold, and reports of burning eyes quadrupled. In the cockpits studied, thermal discomfort and high vibration levels were common. Subjective workload during preflight, taxi, climb, and cruise was related to the crewmembers' ratings of the quality of the aircraft systems. During descent and approach, workload was affected by weather at the landing site. During landing, it was influenced by the quality of the landing site and air traffic control. Beginning duty later, and greater attention to aircraft comfort and maintenance, should reduce fatigue in these operations.

Mannans of the yeast Saccharomyces cerevisiae have been implicated as containing the allergens to which bakers and brewers are sensitive and also the antigen recognized by patients with Crohn's disease. A fraction of S. cerevisiae mannan, Sc500, having high affinity for antibodies in Crohn's patients has been characterized by NMR spectroscopy followed by fragmentation using alkaline elimination, partial acid hydrolysis and acetolysis. The released oligosaccharides were separated by gel filtration on a Biogel P4 column and analyzed by fluorescence labeling, HPLC and methylation analysis. The relationship between structure and antigen activity was measured by competitive ELISA. The antigenic activity of the original high molecular weight mannan could be ascribed to terminal Manalpha1-->3Manalpha1-->2 sequences which are rarely found in human glycoproteins but were over-represented in Sc500 compared to other yeast mannans.

A mineralization and determination method for total iodine in nutritional and biological samples is described. Combustion of the sample in an oxygen stream is followed by collection of the combustion products in a 5% water-soluble tertiary amine solution. Iodine is determined by inductively coupled plasma mass spectrometry. The accuracy and precision of the quantitative iodine analysis using standard addition is better than +/- 10%. A semi-quantitative analysis of four standard reference materials is evaluated. Owing to the presence of low-level iodine contaminant in the blank solution, the determination limit of the method is +/- 10 micrograms kg-1. Good agreement with certified iodine values is obtained for six reference materials. The use of the tertiary amine matrix solution permits the simultaneous determination of iodine and other trace metals of biological and toxicological importance, including Mn, Co, Ni, Cu, Zn, Rb, Cd, and Pb.

A polymorphism of the TNF-beta gene can be detected by restriction digestion of a PCR product with NcoI. In this study we look at the risk associated with this polymorphism in a study of 69 insulin-dependent diabetes patients and 119 healthy controls. The risk was further characterized by comparison to the HLA type of the individual, since the TNF polymorphism is in linkage disequilibrium with HLA genes.

The development and commercial availability of plasma ion source, specifically inductively coupled plasma, mass spectrometers (ICP-MS) have significantly extended the potential application of stable isotopes for nutritional modeling. The status of research and commercial ICP-MS instruments, and their applications and limitations for stable isotopic studies are reviewed. The consequences of mass spectroscopic resolution and measurement sensitivity obtainable with quadrupole, sector, time-of-flight, and trap instruments on stable isotope analysis are examined. Requirements for reliable isotope measurements with practical biological samples including tissues and fluids are considered. The possibility for stable isotope analysis in chemically separated compounds (speciation) also is explored. On-line compound separations by chromatography or electrophoresis, for example, have been combined instrumentally with ICP-MS. Som possibilities and requirements are described for stable isotope speciation analysis.

Soil ingestion estimates were obtained from a stratified, simple random sample of 64 children aged 1-4 years residing on a superfund site in Montana. The study was conducted during the month of September for 7 consecutive days. The study utilized a mass-balance methodology in which eight naturally occurring soil tracers (Al, Si, Ti, Ce, Nd, La, Y, and Zr) believed to be poorly absorbed by the gastrointestinal tract were employed to provide soil ingestion estimates. Food and fecal samples were analyzed on a daily basis. Soil/dust samples representative of where the children played during the study period were obtained. Very high compliance among the participants was maintained throughout the study. The identical methodology employed in the childrens' study was used in an adult study of tracer recovery in 10 subjects over 28 days of observation to provide validation that soil ingestion over the range of 20 to 500 mg/day could be detected. Soil ingestion was estimated by each soil tracer via traditional methods as well as by an improved approach using five trace elements (Al, Si, Ti, Y, and Zr), called the Best Tracer Method (BTM), which substantially corrects for error due to misalignment of tracer input and output as well as error occurring from ingestion of tracers from nonfood, nonsoil sources, while being insensitive to the particle size of the soil/dust ingested. According to the BTM, the median soil ingestion was less than 1 mg/day while the upper 95% was 160 mg/day. No significant age (1 year vs 2, vs 3) or sex-related differences in soil ingestion were observed. These estimates are lower than estimates observed in another study in Massachusetts during September and October. Significant methodological improvements in this study as compared to previously conducted soil ingestion studies include the selection of a representative sample of children, longer study duration, inclusion of dietary recommendations to reduce food tracer input and variability, use of the BTM, and a stronger adult validation study with respect to number of subjects, and duration and range of possible soil ingestion rates. Despite these methodological improvements, evidence exists that this study displays a net residual negative error, suggesting that the above estimates are below the true soil ingestion. The magnitude of this residual negative error cannot be quantified with the BTM but is likely to not affect the median by more than 40 mg/day, while the impact of such an error on the upper end of the distribution is more uncertain.

Zinc is an essential nutrient for growth; however, little is known about zinc kinetics (absorption, distribution, and excretion) in preterm infants (< 38-wk gestation). Zinc kinetics were studied in two preterm infants (gestational ages, 32 and 33 wk) following oral or intravenous administration of a stable isotope (70Zn). Plasma, red blood cells (RBC), urine, and feces were sampled for up to 30 days. Isotope enrichment was measured in tissues by inductively coupled plasma (ICP)-mass spectrometry, and zinc was determined by ICP-atomic emission spectrometry. Data were analyzed by compartmental analysis using SAAM31. Zinc intake increased during the studies, and, because body zinc was not in steady state, both tracer (70Zn) and tracee (Zn) data were fitted using analogous models. A model for adults [M. E. Wastney, R. L. Aamodt, W. F. Rumble, and R. I. Henkin. Am. J. Physiol. 251 (Regulatory Integrative Comp. Physiol. 20): R398-R408, 1986] was modified to fit data from the preterm infants. RBC data were fitted using one compartment (vs. 2 in adults), and an adult RBC subsystem was included in the model to account for zinc introduced during blood transfusions. Exchange of zinc between compartments that were not sampled was based on zinc distribution in neonates. Absorption was 42 and 34%, and endogenous fecal excretion, based on intravenous data, was 15 micrograms.kg-1.day-1. The model can be used to quantify changes in zinc kinetics of preterm infants with age, weight, and zinc intake for evaluating nutritional requirements with growth.

The methodology developed with inductively coupled plasma spectrometry for the determination of marker elements (Al, Si, Ti, Zr, Y, Cr, La, Ce, Cr, and Nd) for childhood soil ingestion in biological (feces), environmental (dust and soil), and food samples are described. The quality assurance-quality control protocol for sample preparation, especially for food, diaper, and fecal samples and for determination of marker elements are presented.

The features of inductively coupled plasma - mass spectrometry (ICP-MS) that make it unique also make possible applications in biological chemistry and biomedical research that would be otherwise difficult or impossible. High sensitivity, characterized spectral interferences, rapid mass scanning, and individual isotope measurements are now combined with sophisticated sample preparation, separations, or stable isotope additions to achieve rapid semi-quantitative analysis, element speciation, and high accuracy. The semi-quantitative analysis of various materials, the separation and detection of macromolecules in blood and other tissues, and tracking of stable isotopes added either purposely or inadvertently to children are important applications of ICP-MS. Current functional limitations and obstacles and potential development areas also are examined.

Murine monoclonal antibodies (mAbs) were selected against a cell wall glycoprotein of Saccharomyces cerevisiae. One of the mAbs (92-276/018) specifically identified S. cerevisiae and the sibling species S. paradoxus, S. pastorianus and S. bayanus in immunofluorescence studies and immunoblot analyses, while no other yeast genera except Saccharomyces were recognized. Further analysis indicated that the mAb 92-276/018 reacts with an epitope in the carbohydrate chain of the cell wall glycoproteins.

This vapour-phase acid decomposition of small biological samples (50-165 mg) and concurrent purification of the reagent acid were achieved in a mini-quartz sample holder inserted in a commercial high-pressure digestion vessel. A 3.1 ml volume sample contained was developed to hold the sample and to maximize the successful decomposition of a variety of biological samples. When biological standard reference materials were digested at 230 degrees C and 122 bar (1770 psi), the residual carbon content in the digested samples was less than 1.8 +/- 0.1%. Inductively coupled plasma atomic emission spectrometric analysis of the digested materials for C, Ca, Cu, Cd, Fe, Mg, Mn and Zn provided good recoveries and low reagent blank values and demonstrated complete matrix decomposition.

Following reports of enhanced humoral immunity to Saccharomyces cerevisiae in patients with Crohn's disease, and identification of an immunodominant, high molecular weight glycoprotein (gp200), we have investigated the cellular immune response to this yeast in normal individuals. Following exposure to a crude saline extract (Sacc), peripheral blood mononuclear cells (PBMC) from these subjects demonstrated dose-dependent increases in tritiated thymidine incorporation, the time-course of which resembled that of the response to the known recall antigens PPD and TT. This was accompanied by increased cytotoxicity of the cultured cells for natural killer (NK)-sensitive and NK-resistant target cell lines. Furthermore, using a purified, high molecular weight, glycoprotein fraction of Sacc in culture, a dose-dependent lymphoproliferative response was again observed. Stimulation indices (SI) for thymidine incorporation by umbilical cord blood lymphocytes exposed to Sacc were low compared with those of normal adults. These results provide evidence for possible antigen-specific, cellular, immune sensitization of normal individuals to a ubiquitous dietary component.

A rapid and accurate method for the inductively coupled plasma atomic emission spectrometric determination of Al, Ba, Si, Sr and Ti in food was developed based on a direct lithium metaborate fusion without sample pre-ashing. Six NIST diet test samples were analysed. Three independent sample preparation procedures were compared for verification.

This study demonstrated that a major feature of childhood atopic eczema (AE) is the presence of serum IgG and IgE anti-house dust mite (anti-HDM) antibodies in almost all AE individuals. IgG anti-HDM antibodies, usually of the IgG1 isotype, became prevalent in AE children over the age of 4 years with the highest antibody levels in children in their early teens. In contrast, immunological sensitization to dietary antigens, notably milk and eggs, occurred in both AE children and age-matched non-atopic control children, and was often associated with IgG4 antibodies during early childhood. These became less prevalent with increasing age in control children but persisted in AE children, sometimes together with IgE antibodies. The later occurrence of anti-HDM antibodies in AE children could reflect immunological sensitization following inhalation of antigen, whereas sensitization to dietary antigens appears to be a natural event in early childhood.

SDS-PAGE analysis of the soluble proteins of the yeast Saccharomyces cerevisiae revealed a single predominant moiety of apparent size 200 kDa which was strongly periodic acid Schiff-positive. In immunoblotting experiments, human sera containing anti-S. cerevisiae antibodies were reactive only with this glycoprotein (gp200); this was demonstrated using sera containing IgG and IgA isotype-specific anti-S. cerevisiae antibodies. The antigenicity of gp200 was substantially reduced by periodate treatment. These results show that gp200 is a major glycoprotein antigen of S. cerevisiae which is immunogenic in man.

The combination of liquid chromatography and inductively coupled plasma/mass spectrometry (ICP/MS) was employed in an exploratory study to determine lead and other trace element species in blood components. In human blood serum, lead was found in at least three molecular weight fractions at greater than 600,000, 260,000, and 140,000. The major part of lead was coincident with the main copper signal at a molecular weight of 140,000. This fraction, binding both copper and lead, was proven to be ceruloplasmin by the application of an immunological reaction prior to chromatographic separation. In rat serum, lead could be detected in four fractions with molecular weights of greater than 600,000, 400,000, 145,000, and 11,000. In human red blood cell hemolysate, the major fraction of lead was found at 250,000, with minor fractions at 140,000 and at 30,000 together with iron in hemoglobin and zinc in carbonic anhydrase. In rat red blood cell hemolysate, lead was detected at greater than 600,000, 145,000, 30,000, and 11,000. Lead isotope ratios were determined in lead binding protein fractions with a precision of +/- 10%. The detection limit for lead in protein fractions was 0.15 micrograms.L-1.

The risk of developing post-herpetic neuralgia is related to the degree of residual scarring. Subjects over the age of 60 with more than 10 cm2 of residual scarring have a very high risk of developing intractable post-herpetic neuralgia. Left-handed subjects are less likely to develop herpes zoster, and this could be due to a more efficient immune system.

The presence of V kappa IIIb light chains in the sera of rheumatoid arthritis (RA) patients has been evaluated by an enzyme-linked immunosorbent assay (ELISA). V kappa IIIb light chains have been confirmed to be largely restricted to IgM, and were rarely detected in the IgG fraction of sera. The concentration of total serum V kappa IIIb did not significantly vary with age, nor did it correlate with IgM-rheumatoid factor (RF) titre. Although total serum V kappa IIIb was not significantly increased in RA patients compared with matched controls, IgM-RFs frequently contained V kappa IIIb. Using flow cytometry, CD5-positive B-cells were not increased in these RA patients compared with healthy laboratory control personnel. Furthermore, there was no direct correlation between total serum IgM V kappa IIIb content and CD5-positive B-cell numbers in peripheral blood.

Six adults were evaluated for the extent to which they ingest soil. This study was originally part of a large childhood soil ingestion study and was used to validate part of the analytical methodology used in that larger study. The adult study followed the soil tracer methodology of the children's study. The principal findings of the adult study revealed that the four most reliable tracer elements based on recovery studies in a mass balance assessment [aluminum (Al), silicon (Si), yttrium (Y), and zirconium (Zr)] yielded the following mean daily adult soil ingestion estimations: Al (77 mg), Si (5 mg), Y (53 mg), and Zr (22 mg). The median daily soil ingestion estimations based on these same tracer elements were: Al (57 mg), Si (1 mg), Y (65 mg), and Zr (-4 mg). These findings represent the first published quantitative estimates of soil ingestion by adults.

Sera from patients with Crohn's disease (CD) and ulcerative colitis (UC) have been evaluated for antibodies reactive with Saccharomyces cerevisiae (anti-Sacc antibodies) using an enzyme-linked immunoassay (ELISA). IgG anti-Sacc antibodies were detected in 63% (25/40) of CD patients, compared with 15% (4/27) of UC patients (p less than 0.001) and 8% (5/60) healthy adult controls (p less than 0.001). Furthermore, the prevalence of detectable IgG anti-Sacc antibodies in adult patients with coeliac disease, dermatitis herpetiformis, irritable bowel syndrome or atopic eczema was not significantly different to controls. In comparison, the prevalence of detectable IgG anti-Escherichia coli antibodies was not significantly different between CD (75%) or UC (79%) patients. More particularly, elevated levels of serum IgA anti-Sacc antibodies were detected in 17/40 CD patients, but in none of the 27 UC patients. These data confirm that serum antibodies reactive with S. cerevisiae are strongly associated with CD and further show that serum IgA anti-Sacc antibodies may be specific for this disorder.

A defined group of 20 women suffering recurrent spontaneous abortions of unknown etiology was studied for determinants relevant to immune responsiveness. A low prevalence of serum anti-CMV antibodies (35%; cf, 65% in controls)--but not anti-herpes-simplex-virus or Epstein-Barr virus antibodies--was noted. Only two (10%) of these women had lymphocytotoxic antibodies following their repeated pregnancies; low titer anti-sperm antibody was present in two other of these women. Whereas there was no significantly increased sharing of HLA-A or -B antigens within these couples compared with controls, there was an increased incidence of apparent HLA-B antigen homozygosity in the women. These data indicate a degree of immunological nonresponsiveness both to cytomegalovirus and to cell-surface alloantigens in habitually aborting women and, together with MLC data, provide further evidence that immunogenetic events may be relevant to reproductive success.

Using a sensitive enzyme-linked immunoassay (ELISA), a significantly increased prevalence (p less than 0.001) of serum antibodies reactive with wheat gliadin, bovine milk or ovalbumin has been demonstrated in 75% (33/44) of adult patients with dermatitis herpetiformis (DH), compared with healthy adults. There was no significant difference in the prevalence of antibodies (79%) in patients on a gluten-free diet or not on a gluten-free diet (72%). These serum antibodies reactive with gliadin, milk and ovalbumin were of the IgG isotype. However, IgA anti-gliadin antibodies were also detected in DH patients, but only in patients who were not on a gluten-free diet. In contrast, IgA anti-milk antibodies were also detected in DH patients irrespective of whether the patient was on a gluten-free diet. In DH patients, antibodies reactive with ovalbumin were often restricted to the IgG4 subclass and antibodies reactive with bovine milk antigens (notably casein) were distributed predominantly in both IgG2 and IgG4 subclasses, a similar IgG isotype distribution to that observed in healthy individuals. However, anti-gliadin antibodies in DH patients showed no predominant IgG4 subclass restriction. IgG4 anti-ovalbumin antibodies and IgG4 and/or IgG2 anti-casein antibodies persisted for up to 4 yr without fluctuation, irrespective of whether DH patients were on a gluten-free diet.

An assay using Laurell rocket immunoelectrophoresis has been developed for quantitation of beta-2-microglobulin (beta 2m) and serial levels of beta 2m have been measured in sera obtained daily from 52 patients following renal transplantation. The RIEP assay was performed using 1% low-endosmosis agarose gels containing 4% polyethylene glycol 6000 and the IgG fraction of rabbit antihuman beta 2m. Elevated beta 2m levels pretransplant fell markedly in the first 48 hr posttransplant in all patients with primary functioning grafts. Base-line control values for serum beta 2m were obtained in patients when stable graft function was established. Serum beta 2m levels increased during renal graft rejection, and significant elevations of serum beta 2m were detected at the onset of all graft rejection episodes as compared with control values. It is suggested that serum beta 2m quantitation by rocket immunoelectrophoresis is a simple and valuable assay to assess posttransplant renal graft function.

HLA typing was performed on 93 patients with persistent palmoplantar pustulosis. The incidence of either HLA B13 or BW17 was not significantly increased as compared to controls. In addition the frequency of BW35 was no different from controls. However, the present results document a significantly increased frequency (38.7%) of B8. Taken together these data are good evidence that palmoplantar pustulosis is a genetically distinct disease entity from psoriasis vulgaris, despite the increased incidence of psoriasis in the condition.

Sera from 262 blood donors were tested against wheat gliadin and bovine milk antigens employing an ELISA system. 9.2% of the sera clearly contained antibodies, predominantly IgG but also including IgA and occasional IgM, reactive with either gliadin (11/262) or milk (13/262). There was no overlap between the gliadin and milk groups, and only one of these sera was also IgE-RAST-positive against wheat or milk. Five of 48 sera with raised IgE levels (greater than or equal to 100 iu/ml) were ELISA-positive against either gliadin or milk, a frequency comparable with that overall in this normal adult population. Six of these 48 sera with raised IgE levels were IgE-RAST-positive against wheat or milk, of which only one was ELISA-positive. These results have indicated that nearly 10% of normal adults have serum IgG/A/M antibodies to milk or gliadin, but that this population is separate from individuals (2.3%) who may be IgE-RAST-positive to the same dietary antigens.

Investigations have been performed in 80 couples with unexplained recurrent spontaneous abortions and no live birth (1 degree RSA), as well as in 33 couples with unexplained RSA following one live birth (2 degrees RSA), compared with control couples with no history of repeated early pregnancy failure. A significant bias towards a family history was given for 1 degree RSA women. Elevated total serum IgE levels and tissue-reactive autoantibodies were not significantly more prevalent in the RSA groups, and both 1 degrees and 2 degrees RSA patients had a similar incidence of serum lymphocytotoxic antibody. HLA typing indicated a trend towards parental HLA sharing which did not achieve clear significance at any locus, whereas there was significant apparent HLA-B locus homozygosity for 1 degree RSA women. An elevated prevalence of HLA-A2, B12 haplotypes was also noted for 2 degrees RSA, which may indicate some form of linkage disequilibrium in this population. These results, overall, did not provide evidence to identify a major subgroup of unexplained RSA patients.

44% of 63 British patients with either haemophilia A or B were HTLV-III antibody positive (HTLV-VIII+). HTLV-III+ was more frequent in high factor VIII concentrate users and 75% of severely affected haemophilia A patients were HTLV-III+. All eight patients who were exposed to factor IX concentrate were HTLV-III-. 17 haemophilia A patients who received only British made factor VIII concentrate (average 12,000 units/year) were HTLV-III-. Two of 63 patients had evidence of a pre-AIDS type symptom complex and both were HTLV-III+. Information from a cohort of 21 Liverpool haemophiliacs suggests that HTLV-III was first introduced into this country in 1981. OKT4/T8 ratios were abnormal in 52% of 21 patients studied but this finding was not confined to either HTLV-III+ or HTLV-III- individuals. The spouses of 14 HTLV-III+ haemophiliacs were all HTLV-III-.

Lewis (LEW) rats immunized 3 weeks before by injection of DNP-KLH together with Bordetella pertussis showed high levels of DNP antibody as judged by serum binding of 10(-7) M 3H-DNP-lysine 10 days after secondary immunization with DNP-KLH. Sera obtained from LEW rats following secondary immunization with DNP-BGG showed reduced DNP hapten binding. However, injection of 10(8) F1 hybrid Lewis X Brown Norway spleen cells into DNP-primed LEW rats 2 days before secondary immunization with DNP-BGG significantly increased the level of serum binding of 3H-DNP-lysine. These results provide evidence that the allogeneic cellular reaction associated with a host-versus-graft response induced by injection of F1 hybrid lymphoid cells into DNP-primed parental strain recipients partially obviates the requirement for carrier-specific T cells in the secondary anti-DNP response thereby providing a stimulus for triggering primed host B cells to produce antibody.

31 clinically defined couples suffering between 3 and 17 consecutive idiopathic spontaneous abortions have been studied. The female partners demonstrated a lower frequency than expected of serum lymphocytotoxic antibodies. Sharing of HLA-A, B or DR antigens was not significantly increased overall within these couples compared with controls, although two couples did show marked HLA sharing (greater than or equal to 4 antigens shared at HLA-A, B and DR loci). There was increased apparent HLA-A and HLA-B locus homozygosity in these women compared with controls (p less than 0.02 and p less than 0.005, respectively), with no significant apparent homozygosity either at HLA-DR or in the males. An increased prevalence of HLA-A, B and DR antigen phenotypes characteristic of various extended haplotypes was also observed in these couples.

Survival of Lewis X Brown Norway F1 renal allografts was prolonged in Lewis recipients by pretreatment with small numbers of donor marrow cells and low dose antilymphocyte globulin(ALG)in combination. Either marrow cells or ALG alone were ineffective at these doses. It was also shown that pretreatment with marrow cells and antilymphocyte serum (ALS) considerably suppressed the local graft-versus-host reaction.

The antigenic specificity of human serum IgG antibodies reactive with common dietary proteins has been evaluated by competitive binding using a solid-phase immunoassay (ELISA). Antibodies reactive with bovine milk antigens were shown to be reactive predominantly with casein, rather than alpha-lactalbumin, beta-lactoglobulin, gamma-globulin or albumin. Furthermore, sera containing antibodies reactive with bovine casein, wheat gliadin and chicken ovalbumin showed competitive binding only by each respective dietary protein antigen. IgG4 antibodies specifically reactive with ovalbumin, gliadin or casein were also not cross-reactive in competitive binding studies. Furthermore, both IgG2 and IgG4 anti-milk antibodies showed significant inhibition only with bovine casein, and not with alpha-lactalbumin or beta-lactoglobulin. These data are relevant to concepts regarding the immunobiological role of antibodies of the IgG4 isotype.

Using a solid-phase immunoassay (ELISA), serum binding to dsDNA, cardiolipin, beta 2-microglobulin (beta 2m) and Keyhole limpet haemocyanin (KLH) has been investigated in patients with systemic lupus erythematosus (SLE). Serum binding to DNA, cardiolipin and beta 2m was significantly increased in SLE sera, compared with normal sera; in addition, serum binding to KLH was also significantly increased. There were, however, no significant correlations between serum binding indices to DNA, beta 2m, cardiolipin or KLH; furthermore, in inhibition experiments no clear cross-reactions of lupus sera for these four ligands were detected. These data indicate that SLE sera bind to DNA, as well as to other apparently diverse ligands. Increased serum binding to these ligands may be attributable to a particular characteristic of the immunoglobulin molecules--or groups of immunoglobulin molecules - produced in these patients.

Although substantial progress has been achieved in inductovely coupled plasma (ICP) spectroscopy, placing it among the principal spectroscopic tools in analytical chemistry research and applications laboratories, some limitations exist especially for the analysis of ultratrace concentration levels in biological materials. The application of chemical and instrumental techniques to increase the concentration levels of analytes is practical, but complicated by the requirements of maintaining the multielement nature of ICP spectroscopy. Two novel chelating resins [poly(dithiocarbamate) and poly(acrylamidoxime)] have been synthesized and applied with ICP spectrometry to enhance the practical sensitivity for ultratrace concentration determinations in biological and other materials. The determination of a number of trace elements in bone, dialysis solutions, serum, and urine is improved using the resin ICP approach. In addition, speciation of inorganic forms of As, Cr, Se, and Te is possible with the poly(dithiocarbamate) resin, and determination of the chemical forms of these elements in urine was performed.

The effects of prior oral administration of erythrocyte membrane preparations (Oral Rh antigen) on the serum anti-Rh(D) antibody response has been evaluated in non-sensitized Rh(D)-negative male volunteers, and in female volunteers sensitized previously by Rh(D)-positive fetal blood during pregnancy. Sixty-one percent (11/18) of males who received oral Rh antigen (either D-positive or D-negative) before intravenous challenge with Rh(D)-positive cells produced detectable antibodies; of these 11, six received oral Rh(D)-negative antigen and five received oral Rh(D)-positive antigen. Seventy-two percent (13/18) of control males, who had received no prior oral Rh antigen, produced antibodies following challenge with Rh(D)-positive cells. Three out of six pre-sensitized females who received oral D-positive or D-negative Rh antigen for 4 weeks, but without intravenous challenge, increased their anti-Rh(D) antibody levels which peaked after 11-18 weeks: two had received Rh(D)-positive antigen, and one Rh(D)-negative antigen. These data indicate that administration of oral Rh antigen before parenteral immunization does not significantly suppress the anti-Rh(D) antibody response. Indeed, oral administration of either Rh(D)-positive or Rh(D)-negative antigen can boost systemic antibody in pre-sensitized females. These results do not support the rationale of treating Rh-sensitized pregnant women with oral Rh antigen.

An example of anti-Gy-a found during routine antenatal testing is the first recorded example in Europe to be described. Five other Gy(a-) siblings were found in the patient's family from whom blood donations were obtained in the event of a needed transfusion. Although anti-Gy-a was detected in the infant's serum, there was no evidence of haemolytic disease of the newborn, presumably due to the fact that the Gy-a antigen is poorly developed at birth.

Guinea-pigs sensitized by subcutaneous injection of chronic lymphatic leukaemia (CLL) cells combined with Bacillus Calmette-Guérin (BCG) displayed good skin reacitons 24 and 48 h after challenge with CLL cells. Equally good responses were also demonstrated using nuclei from the leukaemic cells in combination with BCG. These reactions were significantly greater than those produced in the same manner but without BCG. Sera form the animals were examined for the presence of antibodies against CLL cells by cytotoxicity and immunofluorescence techniques. Only samples from guinea-pigs innoculated with CLL cells were found to contain significant antibodies. Histological examination showed that whereas leukaemic cells persisted at the sensitizing injection site leukaemic cell nuclei could not be visualized. It is suggested that because leukaemic cell nuclei in combination with BCG are able to induce good skin reactivity without provoking a vigorous humoral antibody response they may have possible advantages over leukaemic cells when used for immunotherapy.