Purification of human blood eosinophils by negative selection using immunomagnetic beads.

A simple method for isolating highly purified eosinophils from human blood is described. Buffy coats from normal individuals (eosinophil counts less than 0.4 x 10(9)/litre) were centrifuged through a two layer Percoll density gradient, to produce a granulocyte fraction containing neutrophils and eosinophils. Neutrophils were extracted from this fraction using a monoclonal antibody (CLB FcR gran 1) against CD 16 (Fc gamma R III) in a direct or indirect selection procedure using immunomagnetic beads (Dynabeads). This negative immunoselection produced eosinophils of greater purity and with a superior capacity to mount a respiratory burst than eosinophils isolated by a method employing metrizamide.

Mixed lymphocyte reactions do not predict severity of graft versus host disease (GVHD) in HLA-DR compatible, sibling bone marrow transplants.

Mixed lymphocyte reactions (MLRs) were measured in 25 HLA-A, B and DR compatible sibling bone marrow transplants. Only four of 25 MLRs were positive and in these the low reactivity was of doubtful clinical importance. There was no correlation between MLR and the subsequent development or severity of graft versus host disease (GVHD). A survey of bone marrow transplant units in the United Kingdom showed that most centres perform HLA-DR typing as well as an assessment of the MLR. Factors other than histocompatibility are important in the pathogenesis of GVHD and the data from this study suggest that conventional MLRs can be omitted in HLA-A, B and DR compatible sibling bone marrow transplants.

Oral papillary plasmacytosis resembling candidosis without demonstrable fungus in lesional tissue.

Two cases with exuberant papillary and nodular hyperplasia of the hard and soft palates are described. Both were elderly edentulous men with bilateral angular stomatitis. The papillary hyperplasia extended as far as the epiglottis and was associated with swelling and fissuring of the upper lip in patient 1. In patient 2, the palatal change extended to the maxillary gingiva and was associated with smooth plaques and fissuring of the dorsal tongue. Histology of both cases showed a dense polyclonal plasma-cell infiltrate with overlying epithelial hyperplasia, parakeratinization and neutrophil micro-abscesses suggesting Candida infection but fungal elements could not be demonstrated. Patient 1 also showed defective cellular immunity to Candida antigen which was reversed by treatment with ketoconazole and levamisole, antedating clinical improvement.

Prevalence of oral colonization with Candida albicans and anti-C. albicans IgA in the saliva of normal children and children with acute lymphoblastic leukaemia.

The prevalence of oral colonization with C. albicans was studied in 40 children with acute lymphoblastic leukaemia (ALL) and 40 matched normal children. Colonization was more common in the ALL group (25% colonized) than the normal group (7.5% colonized). Total saliva IgA levels were lower in the ALL group, but low levels did not correlate with oral colonization. The three normal children with oral colonization all had anti-C. albicans IgA in their saliva, as had seven of the ten colonized ALL patients.

Immunodeficiency following neonatal thymectomy in man.

Patients undergoing cardiac bypass operations normally have a thymectomy to facilitate cannulation of the great vessels. Laboratory indices of immune function were measured in 18 children aged 9 months to 3 years who had had a thymectomy when aged 3 months or less, and in two groups of controls individually matched for age and age at operation. Total lymphocyte numbers were similar in all three groups but thymectomized children had significantly lower numbers of T cells and T cell sub-sets than controls and showed diminished responses to phytohaemagglutinin and concanavalin A. Children who have had a thymectomy early in life represent an important group in the study of the development of the immune system in man. Although the clinical consequences of early thymectomy are unclear, evidence of impairment of parameters of immunity have been found in later infancy and routine thymectomy in paediatric cardiac surgery should be avoided.

Suppressor T lymphocyte function in patients with idiopathic congestive cardiomyopathy.

Suppressor T lymphocyte function was examined in 11 patients with idiopathic congestive cardiomyopathy and in 11 age and sex matched patients with a similar degree of heart failure resulting from ischaemic heart disease. Suppressor T lymphocyte function was also assessed in a control population of 11 normal subjects. Suppressor T lymphocyte function was reduced in both groups of patients with heart failure but not significantly, and a wide range of suppression was demonstrated in all groups. These data do not support the hypothesis that there is a defect in T lymphocyte function in patients with congestive cardiomyopathy, but they do suggest that there may be a non-specific reduction in T lymphocyte suppressor function associated with heart failure in general.