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The specificity of six peroxidase-labelled anti-albumin monoclonal antibodies was studied by allowing them to react with albumin-derived fragments of known structure comprising the whole albumin molecule. The epitopes corresponding to these antibodies were located on defined regions of the albumin molecule extending from the N to the C-terminal ends. These antibodies have been used for investigating by ELISA the conformational alterations of albumin molecule brought about by the N-B transition in twelve individual sera. The results do not show any significant differences between the sera. The N-B transition involves essentially the N-terminal portion of the albumin molecule. There also exists as modification of the C-terminal region which is however much less pronounced than the one in the N-terminal region. In addition, it is not observed when using isolated albumin.

A 75 year old man developed chronic flexor tenosynovitis in a finger, caused by Mycobacterium terrae. He had a history of diabetes mellitus and arteritis, but not of local trauma. However, triamcinolone had been injected into the tendon sheath on 3 occasions. Chemotherapy was instituted, but after 3 months amputation became mandatory. This is the fourth case reported in which M. terrae was involved, and it supports the responsibility of this organism as a human pathogen. Attention is drawn to the hazards of corticosteroid injections into tendon sheaths.

Fragments A, B and C obtained by CNBr degradation of human serum albumin (HSA) were studied by specific quantitative precipitation with anti-HSA sera. A co-precipitation has been observed between fragments B and C as well as between C and A which follow each others in the albumin molecule. On the contrary, there was no co-precipitation between fragments B and A which correspond respectively to the N- and C-terminal part of the albumin molecule. Moreover, using inhibition of passive haemagglutination, it has been observed that fragment A does not inhibit anti-B antibodies and fragment B does not inhibit anti-A antibodies. These results indicate that there are common antigenic sites to fragments B and C as well as to C and A but not to B and A. This is in agreement with the data upon the structure of HSA showing that it is made of three domains in linear sequence.

Twelve recent cases of Plasmodium falciparum malaria presented with unusual clinical and laboratory features. All patients had regularly been taking adequate doses of amino-4-quinolines as prophylaxis. In most cases the symptoms were mild as compared with those in a group of 20 control patients with typical malaria. More surprisingly, parasitaemia was either negative or very weakly positive (less than 1000 infested erythrocytes per mm3). All cases occurred in people returning from areas in which resistance of P. falciparum to these drugs is endemic. Diagnostic problems could be solved in most patients by new immunological techniques relying on the detection of parasitized erythrocytes and plasmodium antigens using a battery of monoclonal antibodies. A physiopathological model explaining why parasitaemia is negative in such cases is suggested.

The antigenic structure of a fragment (F1) of human serum albumin (HSA), carrying one of the antigenic sites of the whole molecule, has been studied. Previous studies have shown that this fragment is made of two peptide chains linked by a disulfide bond. One of these chains named alpha has 28 residues and one intrachain disulfide bond giving rise to a loop of 9 or 10 residues. The chain occurs under two forms: the beta chain made of 25 residues and the gamma chain which differs from the beta chain by the absence of the two last C-terminal residues (F. Bellon and C. Lapresle, Biochem. J., 1975, 147, 585-592). The alpha and beta chains both inhibit independantly at 100% the agglutination by an anti-albumin serum of red cells sensitized with F1. Chains alpha, beta and gamma displace anti-HSA antibodies fixed upon an immunoadsorbent prepared with F1. Chain alpha is more active than chain beta which in turn is more active than chain gamma. Reduction and alkylation of alpha and beta chains abolish almost completely their immunological activity. Immunoadsorbents prepared with alpha or beta chains adsorb all of the anti-F1 antibodies from an anti-HSA serum. Antibodies isolated from each chain are inhibited by both chains. Chains alpha and beta induce in rabbits the formation of antibodies reacting with F1 and HSA, alpha chain being a better immunogen than beta chain.

Between April and June 1984, eight chloroquine-resistant P. falciparum malaria cases were observed in non-immune patients after their emergency sanitary return from NE Mozambique. In vivo resistance to amodiaquine and pyrimethamine were demonstrated from two isolates. Radical cure was obtained with mefloquine in all cases. These patients came from an expatriate community of 35 adult men among which six other chloroquine-resistant malarial cases were probable. The epidemic pattern of this chloroquine-resistant focus is underlined.

The authors report the case of an eight-year-old boy who developed erythroderma under carbamazepine. Other findings were enlarged lymph nodes, slight hepatic cytolysis, leuconeutropenia and decrease in the three classes of immunoglobulins. The immunosuppressive effect of the drug is recalled. Respective responsibility of immunosuppression and allergy is discussed.

The case described is one of endocarditis due to lactobacillus casei in a 33-year-old man with aortic insufficiency of undetermined origin. The clinical signs were neurological, following thrombosis of the right posterior cerebral artery. The source of injection was a dental extraction. This case, with a typical clinical picture, is the eleventh to be reported in the literature.

Five proteins (albumin, orosomucoid, IgG, IgM and IgA) were assayed by simple radial immunodiffusion method in the sera of 345 healthy subjects and 5 000 patients suffering from some 200 different diseases. The results were analyzed by computer, and from concomitant changes in individual protein levels it was possible to divide the subjects into eleven groups, each group having a distinctive protein profile. These profiles are characteristic of either a disease (e.g. group VI for virus hepatitis, group VII for trypanosomiasis) or of a physiopathological process (e.g. group II for inflammation, group V for liver damage, group VIII for hypogammaglobulinaemia due to anabolic deficiency and group IX for the same condition due to passage of serum proteins into the extravascular compartment), or they have a prognostic value (e.g. group I).

The high frequency of meningococcal infections in patients with congenital deficiency of a component of the complement terminal pathway emphasizes the critical role of this system in host resistance against Neisseriaceae. We report the observation of a subacute septicaemia due to N. meningitidis serogroup Y. This girl had an acquired deficit of the C3 fraction of complement due to a high titre of C3 nephritic factor (C3NeF). There was no evidence of partial lipodystrophy or biological symptoms of glomerular disease. The meningococcal infection revealed this biological abnormality.

In a 26-year-old man who had spent time in a trypanosome endemic zone, lesions of erythema marginatum progressing by acute exacerbations for 2 years despite various forms of treatment led to the discovery of a multiple lymphadenopathy and a greatly accelerated sedimentation rate. These findings suggested a diagnosis which was confirmed by the discovery of Trypanosoma gambiense in the blood and lymph node aspirate. In addition, there was an albumino-lymphocytic reaction in the cerebrospinal fluid. Finally, an atrioventricular block was discovered. All these symptoms and signs responsed to treatment with melarsoprol but a pericardial reaction developed, possibly of immunoallergic origin.