A study on lymphocyte activation in maedi-visna virus induced pneumonia

The stage of activation of bronchoalveolar lavage fluid (BALF) lymphocytes and peripheral blood lymphocytes (PBL) from maedi-visna virus (MVV) infected (n = 7) and control (n = 7) sheep was investigated by assessing four parameters of lymphocyte activation; lymphocyte size and complexity, loss of CD5+ T cells, expression of cell surface interleukin-2 receptor (IL-2R) and expression of DR and DQ MHC Class II molecules. BALF lymphocytes from MVV-infected animals had a significant loss of CD5+ lymphocytes (P < 0.05) and upregulation of DR and DQ MHC Class II molecules compared with controls, consistent with BALF lymphocyte activation. No changes in cell size and complexity or expression of IL-2R were observed. No evidence of PBL activation was detected. These findings suggest an impaired BALF lymphocyte activation during MVV infection.

Decrease in the alpha 1-proteinase inhibitor Spi3 in equine bronchoalveolar lavage fluid

The alpha 1-proteinase inhibitors of trypsin, Spi1, Spi3A, and Spi3B, in bronchoalveolar lavage fluid (BALF) and serum of horses were separated by electrophoresis, and their proportions were quantified in 12 control horses and 12 with chronic obstructive pulmonary disease (COPD). A significantly lower proportion of Spi3B (P < 0.05) and higher proportion of Spi1 (P < 0.02 to P < 0.01) were detected in BALF, compared with serum, in control and COPD-affected horses and appeared to be attributable to reduced Spi3 activity in BALF. There was no significant difference between the control and COPD groups in this respect, indicating that the decrease in Spi3 may be a physiologic phenomenon. The differences observed may be associated with proteolytic damage to or preferential complex formation by Spi3.

Quantitation of alpha-1 proteinase inhibitor in the pulmonary epithelial lining fluid of horses with chronic obstructive pulmonary disease

The concentration of alpha-1 proteinase inhibitor (API) was measured in the pulmonary epithelial lining fluid (PELF) of horses with chronic obstructive pulmonary disease (COPD) while they had clinical signs and while they had none. The concentrations of total protein, albumin and API were significantly higher in the PELF of animals with clinical signs of COPD. The correlation between albumin and API in the PELF suggested that most of the API was derived from the serum.

Functional relationship between mast cells and C-sensitive nerve fibres evidenced by histamine H3-receptor modulation in rat lung and spleen

1. Mast cell populations in rat lung and spleen were characterized by the presence of two specific protease markers, rat mast cell protease I and II, using both histochemical and radioimmunoassay techniques. Three mast cell populations with different size, morphology, and localization were found in lung and spleen and were identified according to the expression of rat mast cell protease I (RMCPI+) or rat mast cell protease II (RMCPII+) or of both proteases (RMCPI/II+). 2. All three mast cell types were in the vicinity of calcitonin-gene-related-peptide-immunoreactive (CGRP+) nerve fibres in controls as well as in rats infected by Nippostrongylus brasiliensis in which a large increase in the number of both RMCPII+ and RMCPI/II+ mast cells was found. Ablation of the CGRP+ fibres by neonatal treatment with capsaicin resulted in a marked increase in the number of RMCPII+ and RMCPI/II+ cells in lung and, even more, in spleen of adult rats. 3. The interaction of mast cells with CGRP+ C-fibres was assessed pharmacologically by evaluation of the effects of histamine H3-receptor ligands known to act on various types of nerve endings, including those of C-fibres. The effects of H3-receptor ligands were assessed in controls, nematode-infected rats and neonatally capsaicinized rats. Mast cell activity was evaluated by measurement of [3H]histamine synthesis from [3H]histidine. In control rats, administration of the H3-receptor agonist (R)-alpha-methylhistamine and antagonist thioperamide, decreased and enhanced respectively [3H]histamine synthesis in lung and spleen, indicating a tonic control of mast cell activity by histamine via H3-receptors. Such effects were not found in the jejunum, although RMCPII+ mast cells are in close apposition with neuropeptide-containing fibres. The effects of the H3-receptor agents were maintained in lung and spleen of nematode-infected rats, but were almost suppressed in capsaicinized rats. 4. It is concluded that the control of mast cells by histamine acting at H3-receptors involves neuropeptide-containing nerves and presumably reflects the operation of a local neuron-mast cell feedback loop controlling processes such as 'neurogenic inflammation'. This loop still functions when mast cells proliferate in an inflammatory condition. These observations suggest that the use of histamine H3-receptor agonists may constitute a novel therapeutic approach to limit excessive inflammatory responses resulting from dysregulation of this feedback loop.

Fasting or dexamethasone treatment reduce protease content in rat lung mast cells and modulation of histamine synthesis by H3 receptors

The sensitivity of mast cells to H3-receptor modulation was studied in rat lung under various hormonal conditions. The heterogeneity of mast cell sub-populations in rat lung was assessed by the tissue content of rat mast cell protease I (RMCP I) and rat mast cell protease II (RMCP II). After 24 h fasting, concentrations of RMCP I were unchanged whereas the concentration of RMCP II was significantly reduced by 49%. The [3H]histamine (HA) synthesis was concomitantly decreased by 35%. In addition, the modulation of [3H]HA synthesis by the H3 receptor agonist, (R)alpha-methylHA and by the antagonist, thioperamide, observed in control rats, was lost in fasted rats. Single and repeated administrations of dexamethasone did not influence RMCPI concentrations, but decreased the concentrations of RMCP II with a parallel decrease in [3H]HA synthesis. The inhibitory effect of (R)alpha-methylHA on [3H]HA synthesis was also reduced. These results suggest that a subpopulation of RMCP II-containing mast cells, very sensitive to environmental factors, could be the mast cells synthesizing HA in an H3-receptor-dependent manner.

Molecular weight alterations of alpha-1 proteinase inhibitor in equine bronchoalveolar lavage fluid

The equine alpha-1 proteinase inhibitor (alpha 1PI) system differs from that of man in that the equine system consists of four closely-linked genes (Spi1-Spi4) whereas in man, a single gene encodes for alpha 1PI. We have previously found differences in the proportion of the Spi proteins in equine serum and bronchoalveolar lavage fluid (BALF). We therefore wished to determine whether, as reported in man, there was any molecular weight difference between the Spi proteins in serum and BALF. alpha 1PI and albumin from equine BALF migrated further towards the anode compared with serum alpha 1PI on native polyacrylamide gel electrophoresis (PAGE) although the difference was only significant for alpha 1PI. Sodium dodecyl sulphate-PAGE (SDS-PAGE) showed that a mean decrease in molecular weight of 1.5 kDa for alpha 1PI and 1.3 kDa for albumin had occurred in BALF. These findings were observed in control animals and in those with symptomatic or asymptomatic chronic obstructive pulmonary disease. The mechanism of this decrease in molecular weight of alpha 1PI is likely to differ from reports of alpha 1PI cleavage by bacterial proteinases in man since the molecular weight change was relatively small and loss of trypsin inhibitory activity did not occur. Nor, in our system, was there evidence of bacterial infection. Damage by endogenous proteinases or glycosidases at a site other than the reactive site may be involved but the resultant effect on the efficiency of the antiproteinase screen of the lower respiratory tract is uncertain.

Development and validation of the Stirling Eating Disorder Scales

The development and reliability/validity check of an 80-item, 8-scale measure for use with eating disorder patients is presented. The Stirling Eating Disorder Scales (SEDS) assess anorexic dietary behavior, anorexic dietary cognitions, bulimic dietary behavior, bulimic dietary cognitions, high perceived external control, low assertiveness, low self-esteem, and self-directed hostility. The SEDS were administered to 82 eating disorder patients and 85 controls. Results indicate that the SEDS are acceptable in terms of internal consistency, reliability, group validity, and concurrent validity.

Measurement by ELISA of equine alpha-1-proteinase inhibitor in uterine flushings from mares

An enzyme linked immunosorbent assay (ELISA) was developed and used to estimate the concentrations of the serine proteinase inhibitor, alpha-1 proteinase inhibitor (API), in uterine flushings recovered from mares at different stages of the oestrous cycle and before and after the induction of experimental endometritis. There was a significant increase in the concentrations of API and albumin relative to total protein in flushings recovered during oestrus compared with dioestrus but no difference was observed in the concentrations of these proteins relative to total protein before and after the induction of endometritis. A regression analysis revealed a significant correlation between the concentrations of albumin and API in the flushings examined, suggesting that the API was derived entirely from serum and was not produced locally in the uterus.

Hepatic recruitment of mast cells occurs in rats but not mice infected with Schistosoma mansoni

The pathogenesis of infection with Schistosoma mansoni in rats is distinct from that in mice. Rats are non-permissive hosts and infection is terminated in the liver before egg laying commences whereas the parasites completes its life cycle in mice. Comparison of the mast cell responses in the two species reveals that a pronounced hepatic mastocytosis occurs in the rat and this is concomitant with the demise of the parasite. The majority of recruited hepatic mast cells contain the highly soluble granule chymase, rat mast cell protease-II, which is released systemically into blood during the period of parasite elimination. In contrast, very few mast cells are found in livers of parasitized mice and none contain the soluble granule chymase mouse mast cell protease-1. However, during egg deposition in the gut, an intraepithelial mastocytosis occurs in parasitized mice. These intraepithelial cells are typical mucosal mast cells as determined by their content of mouse mast cell protease-1. Recruitment of mucosal mast cells occurs in the intestinal lamina propria of infected rats soon after the parasites migrate to the liver. These findings suggest that mast cells of the mucosal phenotype are involved in the pathogenesis of the hepatic response to infection in the rat but that, in the mouse, mucosal mastocytosis is associated with intestinal sensitization by egg antigens.

Characterization of cultured mast cells derived from Ws/Ws mast cell-deficient rats with a small deletion at tyrosine kinase domain of c-kit

The Ws mutant allele of rats represents a 12-base deletion at the tyrosine kinase domain of the c-kit gene. Although homozygous Ws/Ws rats were deficient in both connective tissue-type mast cells (CTMC) and mucosal-type mast cells (MMC), mast cells did develop when bone marrow cells of Ws/Ws rats were cultured in the presence of concanavalin A-stimulated spleen cell conditioned medium (ConA-SCM). Although the proliferative response of rat cultured mast cells (RCMC) derived from Ws/Ws rats to ConA-SCM was comparable to that of RCMC derived from control normal (+/+) rats, the proliferative response of Ws/Ws RCMC to rat recombinant stem cell factor (rrSCF; a ligand for the c-kit receptor tyrosine kinase) was much lower than that of +/+ RCMC. However, a slight c-kit kinase activity was detectable in Ws/Ws RCMC, and the proliferation of Ws/Ws RCMC was accelerated when rrSCF was added to ConA-SCM. Because CTMC contain rat mast cell protease-I (RMCP-I) and MMC contain RMCP-II, the phenotype of +/+ and Ws/Ws RCMC in various culture conditions was evaluated by immunohistochemistry of RMCPs. Both +/+ and Ws/Ws RCMC showed the MMC-like phenotype (RMCP-I-/II+) when they were cultured with ConA-SCM alone. Most +/+ RCMC and about half of Ws/Ws RCMC acquired a novel protease (RMCP-I+/II+) phenotype when they were cultured with rrSCF alone. However, because the number of Ws/Ws RCMC dropped to one-tenth in the medium containing rrSCF alone, the absolute number of Ws/Ws RCMC with the RMCP-I+/II+ phenotype did not increase significantly. The effect of rrSCF in inducing the novel phenotype was suppressed when ConA-SCM was added to rrSCF. In contrast, +/+ and Ws/Ws RCMC cocultured with +/+ fibroblasts showed the RMCP-I+/II+ phenotype even in the presence of ConA-SCM. Moreover, a fibroblast cell line derived from SI/SI mouse embryos that did not produce SCF did not support the survival of both +/+ and Ws/Ws RCMC but did induce the RMCP-I+/II+ phenotype in about half of +/+ and Ws/Ws RCMC when their survival was supported by the addition of ConA-SCM. The normal signal transduction through the c-kit receptor did not appear to be prerequisite for the acquisition of the RMCP-I+/II+ phenotype.

Effects of stem cell factor (kit-ligand) and interleukin-3 on the growth and serine proteinase expression of rat bone-marrow-derived or serosal mast cells

The effects of rat stem-cell factor (SCF) and interleukin-3 (IL-3), alone or in combination, on the in vitro growth and serine proteinase expression of rat serosal/connective-tissue mast cells (CTMC) or bone marrow-derived mast cells (BMMC) were examined. Rat SCF stimulated the growth of both CTMC and BMMC. IL-3 stimulated BMMC growth to a lesser extent than did SCF, whereas CTMC numbers did not increase in IL-3. However, SCF and IL-3 had synergistic effects on the growth of both BMMC and CTMC. SCF favoured the maintenance of rat mast cell proteinase-I (RMCP-I) in CTMC, but did not induce detectable production of RMCP-I in BMMC. In contrast, when IL-3 or lymph node-conditioned medium (LNCM) was added to SCF, a subpopulation of CTMC expressed and stored the soluble proteinase RMCP-II. In BMMC, the RMCP-II content of cells maintained in SCF was significantly less than that of cells maintained in IL-3 or LNCM. RMCP-II also appeared in the supernatants of BMMC, especially when BMMC numbers were increasing rapidly in SCF with or without IL-3 or LNCM. Thus, SCF and IL-3 can regulate the growth of rat BMMC and CTMC, as well as influence their production and release of proteinases.

Altered expression of mast cell proteases in the rat. Quantitative and immunohistochemical analysis of the distribution of rat mast cell proteases I and II during helminth infection

Expression of mast cell granule protease is regulated in a tissue-specific fashion in the rat. The granule chymases rat mast cell proteases I and II (RMCP I and II) predominate in non-mucosal and mucosal sites, respectively. Intestinal mastocytosis, a T cell-mediated phenomenon associated with enteric nematodiasis, is accompanied by massive local expression of RMCP II and by release of this protease systemically into blood. The present observations, where both RMCP I and II have been quantified by ELISA and immunolocalized by paired fluorescence, show that the expression of both proteases in parasitized rats is profoundly altered at sites distant from infection. Thus, RMCP II-containing cells are recruited to liver and thymus, and in the thymus there is a > 2-fold increase in concentration of RMCP I. The latter protease is depleted from bone marrow and mesenteric lymph node early during infection, but concentrations of RMCP I in trachea/larynx, lung, and skeletal and cardiac muscle are increased. Increased mast cell counts in intestine, lung and liver are highly correlated with tissue concentrations of RMCP II.

Comparative studies of the Spi1 proteins of three equine alpha-1-proteinase inhibitor haplotypes following isolation by affinity chromatography

1. Antiproteinase deficiency can result in excessive proteinase-induced tissue damage. The major anti-elastase (Spi1) protein of equine alpha 1-proteinase inhibitor (alpha 1-PI) was isolated from the plasma/serum of three common haplotypes (I, L and U). 2. The N-terminal amino acid sequences of the three inhibitors were identical, but were only approx 65-77% homologous with two other published equine Spi1 sequences. 3. All three inhibitors complexed quickly and irreversibly with equine leucocyte proteinase 2A (kass = 2 x 10(7) M-1 sec-1). They were also efficient inhibitors of chymase (rat mast cell proteinase-II; kass = 2 x 10(5) M-1 sec-1; Ki = 2 x 10(-10) M). There was therefore no evidence of deficient inhibition in the Spi1 variants of the I,L and U haplotypes.

Biochemical and immunological characterization of multiple glycoforms of mouse mast cell protease 1: comparison with an isolated murine serosal mast cell protease (MMCP-4)

Five highly soluble, chymotrypsin-like, neutral serine proteases, with molecular masses in the range 30-33 kDa, were isolated from Trichinella spiralis-infected mouse small intestine. These enzymes were closely related antigenically on Western blotting and by Ouchterlony double diffusion using a polyclonal, cross-absorbed, sheep antibody raised against mouse mast cell protease-1 (MMCP-1) and on the basis of N-terminal amino acid sequence analysis, were identified as variant forms of MMCP-1. Substrate and inhibitor analysis confirmed that the five variants (MMCP-1 A-E) had similar characteristics, although highly significant (P = 0.025 to P < 0.0001) variations in Km and kcat, were detected. Against human alpha 1-proteinase inhibitor the Ki for MMCP-1C (45 pM) was significantly (P < 0.0001) greater than those for the other proteases (0.76-2.2 pM). The differences in electrophoretic mobility are probably a result of variable glycosylation, since removal of N-linked carbohydrate produced a polypeptide of approx. 28 kDa in each case which was, like the native enzyme, immunoreactive on Western blotting. A much less soluble 28 kDa enzyme was isolated from serosal mast cells and identified as MMCP-4 by N-terminal amino acid sequencing. Like MMCP-1 it has chymotrypsin-like substrate specificities with activity at neutral pH. However, it was antigenically distinct from MMCP-1 and, using sheep anti-MMCP-1, was not detected on Western blotting or by Ouchterlony double diffusion, e.l.i.s.a. or immunohistochemistry. This last technique established that the MMCP-1 variants were uniquely present in enteric mast cells, thereby providing a highly selective means of distinguishing the mucosal and connective tissue mast cell subsets in the mouse.

Quantitative and cytochemical studies of mast cell proteases in rat ovaries and uteri in various reproductive states

A role for mast cell proteases (RMCP I and II) in the cyclical remodelling of ovarian and uterine tissues of rats was investigated in the oestrous and pregnancy cycles using immunocytochemistry and enzyme-linked immunosorbent assays. The concentrations of RMCP I exceeded that of RMCP II by 100-fold in both tissues, but were always much higher in uteri than ovaries. Most of the protease activity in the uterus was located in the myometrium, whereas it was more focally distributed in the hilus and medulla of the ovary. Protease activity was confined to mast cells identified by metachromatic staining and no single cell contained both proteases. The concentrations of RMCP I and II in the two organs did not fluctuate throughout the 4-day oestrous cycle. Neither were RMCP I concentrations in the uterus altered by administration of diethylstilboestrol to ovariectomized animals, although total amounts per uterus were substantially greater than in the controls. Concentrations of RMCP I were substantially reduced in the uterus after day 6 of pregnancy and rose during the puerperium. The reduction was greater in pregnant than in pseudopregnant horns and tended to be lower in the vicinity of conceptuses than between them. The physiological significance of the lower mast cell protease concentrations is unclear, although their absence may contribute to the decreased protein catabolism during pregnancy.

Neutrophil chemotaxis in the horse is not mediated by a complex of equine neutrophil elastase and equine alpha-1-proteinase inhibitor

Studies have demonstrated that as a result of proteolytic inactivation or complex formation (with neutrophil elastase), human alpha-1-proteinase inhibitor (API) becomes a potent chemoattractant for human neutrophils. The present study aimed to investigate the in vitro chemotactic response of equine neutrophils to an equivalent complex of equine API and neutrophil elastase. No evidence of neutrophil migration was observed towards purified complex derived from equine neutrophil elastase and the Spi 1 isoform of equine API, or to crude mixtures of porcine pancreatic elastase and unseparated equine API isoforms, although the same neutrophil preparations actively migrated towards zymosan activated plasma. It was concluded that, in the horse, complexes of API are not involved in the migration of neutrophils to sites of inflammation.

MCMI-II item weights: their lack of effectiveness

Millon Clinical Multiaxial Inventory II (MCMI-II; Millon, 1987) results from 134 patients were scored twice; with and without the item weights. The results showed that the correlations between the weighted and unweighted versions of the same scales were extremely high, exceeding .90 in all cases. Furthermore, weighting did not significantly reduce the correlations among the scales, either within each of the four syndrome/pattern categories of the MCMI-II, or between categories. It is concluded that item weighting reduces the access of the MCMI-II by clinicians, without increasing its psychometric properties.

The effects of the modifier and correction indices on MCMI-II profiles

Five modifier and correction indices are used in the Millon Clinical Multiaxial Inventory-II (MCMI-II; Millon, 1987) to improve the sensitivity and specificity of its scales; however, profile analyses indicated that they had little effect on the profiles of 141 psychiatric inpatients. The profiles generated within each MCMI-II section with and without the indices had the same shape and generally showed no significant differences on the various scales. A simple procedure applied to the initial, uncorrected scores provided a good estimate of the final base rate (BR) scores that are obtained when the correction and modifier indices are applied. Examination of individual profiles indicated that the 3-point codetypes were usually the same regardless of whether or not the correction indices were applied. When there were changes, these usually involved changes in rank order; new scales were rarely introduced in a code type. Although the utility of the indices for assessing test-taking attitude remains to be determined, these results argue against their use for modifying BR scores.

Infection of Nippostrongylus brasiliensis induces development of mucosal-type but not connective tissue-type mast cells in genetically mast cell-deficient Ws/Ws rats

Ws/Ws rats have a small deletion at the tyrosine kinase domain of the c-kit gene and are deficient in both mucosal mast cells (MMC) and connective tissue-type mast cells (CTMC). The role of the c-kit receptor in the development of MMC and CTMC was investigated by infecting Ws/Ws and control +/+ rats with Nippostrongylus brasiliensis (NB), which induces T-cell-dependent mast cell proliferation. Although mast cells did not develop in the skin of Ws/Ws rats, a significant number of mast cells developed in the jejunum after NB infection. These mast cells had the MMC protease phenotype (rat mast cell protease [RMCP] I-/II+) and lacked heparin because they were not stained with berberine sulfate. Globule leukocytes were also detected in the mucosal epithelium of these rats. However, the number of MMC and the serum concentration of RMCP II in NB-infected Ws/Ws rats were only 13% and 7% of those of NB-infected +/+ rats, respectively. A small number of mast cells also developed in the lung, liver, and mesenteric lymph nodes of Ws/Ws rats after NB infection. Although mast cells in these tissues had the MMC phenotype throughout the observation period, the increased mast cells in the lung and liver of +/+ rats acquired a CTMC-like phenotype and were RMCP I+/II+, berberine sulfate+, and formalin resistant. These results indicate that the need for the stimulus through the c-kit receptor appears to be greater in the development of CTMC in the skin as well as for CTMC-like mast cells in the lung and liver than for the development of MMC.

Maximum likelihood estimates of the ability of the MMPI and MCMI personality disorder scales and the SIDP to identify personality disorders

The ability of the Minnesota Multiphasic Personality Inventory (MMPI) and Millon Clinical Multiaxial Inventory (MCMI) personality disorder scales and the Structured Interview for DSM-III Personality Disorders (SIDP) to identify personality disorders was estimated statistically using 122 subjects. Each technique was reasonably accurate when various diagnoses were excluded, but they were quite variable in identifying members of specific diagnostic categories. The same general pattern was seen when the disorders were combined into three general diagnostic clusters. The techniques excluded cluster membership fairly well, although there was little agreement across techniques for identifying cluster membership. The MCMI, however, was moderately adept at identifying membership in all three clusters. It was suggested that these instruments should be used cautiously in clinical settings and that additional data on their performance be obtained.

The influence of challenge dose, duration of immunity, or steroid treatment on mucosal mast cells and on the distribution of sheep mast cell proteinase in Haemonchus-infected sheep

The distribution of granule-specific sheep mast cell proteinase (SMCP), was assayed by immunocytochemistry and quantified by immunoassay in sheep immune to Haemonchus contortus. Repeated infection with Haemonchus larvae over 10-12 weeks induced a pronounced mucosal mastocytosis, including intraepithelial globule leukocytes (GL), which, 7 days after ceasing this dosing regime, was associated with the inability of incoming larvae to establish within the abomasal mucosa. Loss of this resistance, due to the cessation of stimulation with Haemonchus larvae 84 days previously or to treatment of sheep with corticosteroid, was associated with a marked decline in mast cell density and concentrations of SMCP in abomasal mucosal tissues. Nevertheless, larvae also failed to establish in immune sheep rested from challenge 42 days previously and in which mast cell counts were not significantly different from those of control sheep. A small, but significant, release of SMCP was demonstrated in gastric mucus from immune sheep following larval challenge, whereas little or no SMCP was detected in mucus from naïve animals.

Ultrasonographic evaluation of acute appendicitis

Twenty-one patients with a clinical diagnosis of acute appendicitis underwent graded compression ultrasonography as an ongoing clinical study. The findings at surgery were compared with the ultrasonographic findings. There were no false-positive, 8 false-negative, 9 true-positive, and 11 true-negative results. The specificity was 100% and sensitivity, 52.9% The findings of this study, in contrast to findings of other recently reported studies, demonstrates that ultrasonography is a poor modality with which to evaluate acute appendicitis.

Differential inhibition of rat mast cell proteinase I and II by members of the alpha-1-proteinase inhibitor family of serine proteinase inhibitors

Rat mast cell proteinase II (RMCP II) from mucosal mast cells was titrated into rat serum, and the resulting serine proteinase inhibitor (serpin)-enzyme complex was purified by affinity chromatography on anti-RMCP II-Sepharose 4B and by Mono-Q anion-exchange. The purified complex was used to raise polyclonal antibodies which, after cross-absorption against RMCP II-Sepharose 4B, were specific for serpin and were used to affinity purify two rat serpin molecules (RSI and RSII) that inhibit RMCP II in rat serum. The kinetic constants characterizing the interaction between RMCP II and RSI and RSII are ka, 2.2 x 10(5) and 1.65 x 10(5) M-1 s-1, respectively; Ki, 3.6 x 10(-10) and 1.0 x 10(-9) M; and kd, 7.9 x 10(-5) and 1.65 x 10(-4) s-1. Amino-terminal sequence analysis indicated that RSI and RSII are distinct, differing at the amino-terminal residues, and are products of the rat Spi-1 locus. Rat mast cell proteinase I (RMCP I) from connective tissue mast cells cleaved both RSI and RSII and was not inhibited.

Immune responses of the ovine lymph node to Chlamydia psittaci. A cellular study of popliteal efferent lymph

The popliteal efferent lymphatics were cannulated in sheep of two categories, seronegative or immune to Chlamydia psittaci. Following subcutaneous injection of live C. psittaci or control material into the draining area of the popliteal node, sequential samples of efferent lymph were collected and analysed. Both categories of sheep responded to C. psittaci with increased outputs of lymphocytes and blast cells. Numbers of blast cells rose both absolutely and as a proportion of the total. Plasmablasts increased in number only in seronegative sheep. Outputs of total T cells (CD5+), helper T cells (CD4+), cytotoxic/suppressor T cells (CD8+) and non-helper, non-suppressor T cells (T19) were maximal 4 and 7 days after challenge in immune and seronegative sheep, respectively. Proportionally, CD4+ T cells declined, CD8+ T cells increased and T19 cells were unaltered with time after infection. Chlamydial antigens could not be demonstrated in the cells of efferent lymph by an immunoperoxidase method. The results of this preliminary study show that both T and B cell responses are involved in immunity to C. psittaci.