Rapid re-expression of CD45RC on rat CD4 T cells in vitro correlates with a change in function.

Rat CD4+ T cells are divided phenotypically by the anti-CD45RC monoclonal antibody OX22 into subsets with contrasting functions. Stimulation of T cells in vitro is known to induce a change in isoform from CD45RC+ to CD45RC-. We have investigated the in vitro conditions which promote a switch in isoform in the opposite direction.

Identification of an immunodominant B-cell epitope in bovine type II collagen and the production of antibodies to type II collagen by immunization with a synthetic peptide representing this epitope.

Using epitope scanning of 272 short, synthetic peptides representing the amino acid sequence of the CB-11 peptide of type II collagen, we have shown that five strains of rat, immunized with type II collagen, produce antibodies to a region 37-45 amino acids from the amino end of CB-11 peptide. Antibodies to this region always gave the highest binding values suggesting that it is an immunodominant region. Wistar rats immunized with a synthetic peptide representing this region, coupled to keyhole limpet haemocyanin, produced antibodies to this peptide which could still be detected at 1:4000 to 1:8000 dilution but none developed clinical arthritis.

Growing tips of type I collagen fibrils formed in vitro are near-paraboloidal in shape, implying a reciprocal relationship between accretion and diameter.

Collagen fibrils generated in vitro at 37 degrees C by enzymic removal of C-terminal propeptides from type I pC-collagen (an intermediate in the normal processing of type I procollagen to collagen containing the C-terminal propeptides but not the N-terminal propeptides) display shape polarity, with one tip fine tapered and the other coarse tapered. Mass measurements by scanning transmission electron microscopy show that the mass per unit length along both kinds of tip increases roughly linearly over distances of approximately 100 D periods from the fibril end [D (axial periodicity) = 67 nm]. The fine tips of fibrils of widely differing lengths exhibit near-identical mass distributions, the mass in all cases increasing at the rate of approximately 17 molecules per D period, irrespective of fibril length.

Amyloid in prostatic corpora amylacea.

Aim: To determine the presence and nature of amyloid in prostatic corpora amylacea using immunohistological studies.

Methods: Prostatic tissue from 18 transurethral and two open resection specimens was studied. Paraffin wax embedded tissue sections were stained with haematoxylin and eosin and the alkaline Congo red method with and without previous treatment with potassium permanganate.

Milestones in cystic fibrosis.

The study of cystic fibrosis (CF) provides a fascinating insight into developments in medicine in the 20th century. Milestones include the first clear clinical descriptions in the 1930s, discovery of a sweat electrolyte abnormality, establishing the autosomal recessive mode of inheritance and improvements in treatment. Microdissection experiments on sweat glands allowed the main defect to be delineated as one of chloride transport.

Clamped homogeneous electric field gel electrophoresis typing of Torulopsis glabrata isolates causing nosocomial infections.

Thirty isolates of Torulopsis glabrata were examined by pulsed-field gel electrophoresis, which resolved 13 DNA pieces, allowing the identification of 12 types. Bands at 1,400, 1,200, 1,070, 1,025, 681, and 500 kbp were conserved. When applied to 18 isolates from an outbreak, 10 distinct types were identified by this technique.

Analysis of the depressant effect of the endothelium on contractions of rabbit isolated basilar artery to 5-hydroxytryptamine.

1. The effects of endothelium removal and of a number of pharmacological agents known to modify endothelial cell function on the contractile response of rabbit isolated basilar arteries to 5-hydroxytryptamine (5-HT) and other vasoconstrictors were studied. 2.

Monoclonal antibody epitopes of mycobacterial 65-kD heat-shock protein defined by epitope scanning.

The binding sites for MoAbs to the 65-kD heat-shock protein (hsp65) of mycobacteria have been investigated by epitope scanning. Five hundred and twenty-six 8-mer peptides representing the complete sequence of Mycobacterium tuberculosis hsp65 were synthesised in duplicate using the Epitope Scanning Kit (CRB Ltd.).

Anabolic effects of clenbuterol on skeletal muscle are mediated by beta 2-adrenoceptor activation.

The potent anabolic effects of the beta 2-adrenoceptor agonist clenbuterol on skeletal muscle have been reported to be independent of actions on beta-adrenoceptors. In the present study clenbuterol, presented to rats in the diet (4 mg/kg), caused significant increases in gastrocnemius muscle mass, protein, and RNA content and a decrease in epididymal fat pad mass. These effects were not mimicked by oral administration of the beta 2-adrenoceptor agonist salbutamol even at high dose (52 mg/kg diet), and the effects of clenbuterol were not inhibited by addition of DL-propranolol (200 mg/kg diet).

Studies of the microvascular endothelium in uninvolved skin of patients with systemic sclerosis: direct evidence for a generalized microangiopathy.

Various parameters for assessing endothelial cell (EC) metabolism, including immunohistochemistry and adenosine uptake, have been compared in the clinically uninvolved skin of patients with diffuse systemic sclerosis (DSS), CREST, incomplete CREST syndrome (ICREST), primary Raynaud's disease (1 degree RD) and normal controls. Evidence of platelet adhesion to EC, decreased EC storage of factor VII-related antigen, changes in EC morphology and decreased adenosine uptake by EC, were found in the dermal microvasculature of normal skin of patients with DSS, CREST and ICREST, but not in 1 degree RD. These data indicate that a generalized microvascular endothelial dysfunction is present in the skin of patients with the systemic forms of scleroderma.

The genetic epidemiology of rheumatoid arthritis.

This review considers the epidemiological aspects of the genetic investigation of rheumatoid arthritis (RA). Problems both of disease definition and disease heterogeneity render studies difficult to undertake and interpret. The selection of individuals both in population and family studies can explain divergent results.

Restriction endonuclease analysis of Aspergillus fumigatus DNA.

Aims: To develop a genome based DNA fingerprinting system for Aspergillus fumigatus mould.

Methods: DNA was extracted from 21 isolates obtained from eight patients with an aspergilloma. This was with a freeze-dried mycelial extract fragmented in liquid nitrogen.

Is Bordetella pertussis clonal?

Objective: To establish whether Bordetella pertussis is essentially clonal.

Design: Analysis of restriction fragments of XbaI digests of DNA from clinical and control isolates of B pertussis by pulse field gel electrophoresis.

Materials: 105 isolates of B pertussis: 67 clinical isolates from throughout the United Kingdom and 23 from Germany (collected during the previous 18 months); vaccine strains 2991 and 3700; and 13 control isolates from Manchester University's culture collection.

Type II collagen induced arthritis: comparison of histological changes in arthritis-susceptible and arthritis-resistant rats.

Wistar rats (type II collagen-induced arthritis-susceptible) and PVG.RT1u rats (arthritis-resistant) were immunised with type II collagen and histological changes in the synovial tissues of the hind feet and in the popliteal lymph nodes draining these feet were examined and compared with unimmunised rats. There were no apparent differences in the joints of unimmunised rats of each strain, but the popliteal lymph nodes of the Wistar rats appeared more "activated", suggesting possible differences between strains in the continuous, low-grade release of antigens from the joints.

Evaluation of Mast-ID 15 system for identification of fresh clinical isolates of Enterobacteriaceae and Acinetobacter.

Aims: To assess the accuracy of the Mast-ID 15 system compared with API 20 E for the identification of stock and fresh clinical strains of Enterobacteriaceae and Acinetobacter spp; to compare the accuracy of 19 pin and 36 pin multipoint inoculator heads.

Methods: One hundred frozen stock cultures of Enterobacteriaceae and Acinetobacter spp which had previously been identified by the API 20E were classified by the Mast-ID using 19 and 36 pin multipoint inoculator heads. Reproducibility was determined by testing 36 randomly selected organisms in duplicate.

Genetic control of the immune response to collagen by the major histocompatibility complex in the rat: I. Humoral responses to bovine and chick type II collagen.

A number of congenic and recombinant rat strains with different RT1 haplotypes on a PVG/c background were immunised with native bovine or chick type II collagen. Only strains with the "u" haplotype were good responders to bovine type II collagen whilst all strains responded to chick type II collagen. However, the "u" haplotype was again associated with the production of the highest amounts of antibody.

The diagnostic potential of synovial effusion in meniscal pathology.

During a 20-month period, 382 arthroscopies were performed and the type of washout fluid obtained was noted. When a torn meniscus was found, the fluid was macroscopically abnormal in 97.4% of cases.

Studies of luminal and mucosal pH in reflux esophagitis and antral gastritis.

Luminal and mucosal pH were measured endoscopically in patients with reflux esophagitis and antral gastritis and in control subjects. In all subjects, significant lumen-to-mucosa gradients were observed in the esophagus, stomach and acidified proximal duodenum. In the reflux patients luminal pH was lower in the fundus (mean +/- SEM, control vs.

HLA haplotype sharing in rheumatoid arthritis sibships: risk estimates in siblings.

The distribution of the number of parental HLA haplotypes shared by sibs with rheumatoid arthritis (RA) has been used to obtain information on the genetics of the disease. Thirty-four RA sibships (25 sib-pairs, 9 sib-trios) were ascertained, all of which were HLA typed and which satisfied the 1958 American Rheumatism Association criteria for "definite" RA. These were combined with other published but nonoverlapping data from the literature; thus, 143 sib-pairs, 36 sib-trios and 4 sibquads were identified.

Absence of autoimmunity to type II collagen in generalised nodal osteoarthritis.

A cardinal feature of generalised nodal osteoarthritis is the loss of articular cartilage. To determine if autoimmunity to these cartilage collagens occurred, serum antibodies to native and denatured type II collagen were measured by enzyme linked immunosorbent assay (ELISA) in 96 patients (90 women, six men, aged 47-91 years) with generalised nodal osteoarthritis. Generalised nodal osteoarthritis was diagnosed by typical clinical and radiological features.

Cellular mechanisms of allograft rejection.

It is generally agreed that a multiplicity of mechanisms are involved in the rejection of various grafts across different histocompatibility barriers. Recent publications have concentrated less on the characterization of the cells involved in the rejection process and more on their initial activation and their infiltration into the graft.