Safety and immunogenicity of a three-component blood-stage malaria vaccine in adults living in an endemic area of Papua New Guinea.

A Phase I safety and immunogenicity study with a three-component blood-stage malaria vaccine was conducted in adult male subjects living in an endemic area of Papua New Guinea. The preparations were recombinant proteins which corresponded to parts of the two merozoite surface proteins of Plasmodium falciparum (MSP1 and 2), and of the ring-infected erythrocyte surface antigen (RESA). The three proteins were emulsified with the adjuvant Montanide ISA720.

Isoniazid plus sulphadoxine-pyrimethamine can reduce morbidity of HIV-positive patients treated for tuberculosis in Africa: a controlled clinical trial.

An annual 20% excess mortality rate is observed in HIV-seropositive patients after treatment for tuberculosis. An affordable secondary prophylaxis against main opportunistic diseases is needed, i.e.

[NANP]19-5.1. A malaria vaccine field trial in Nigerian children.

[NANP]19-5.1 is a recombinant Plasmodium falciparum vaccine consisting of 19 repeats of the sporozoite surface protein [NANP] and the schizont export antigen 5.1.

Mefloquine-sulphadoxine-pyrimethamine (Fansimef, Roche) in the prophylaxis of Plasmodium falciparum malaria: a double-blind, comparative, placebo-controlled study.

From July 1987 to June 1988 a randomized, double-blind, comparative placebo-controlled field trial was conducted in a group of villages near Ibadan, Nigeria. The aim of the study was to assess the suppressive tolerability and efficacy of four antimalarials (Fansimef, Lariam, Fansidar, chloroquine) given for 24 weeks. Fansimef and Lariam were given with loading and maintenance doses, Fansidar and chloroquine as one tablet per week for 24 weeks.

Evaluation of 5.1-[NANP]19, a recombinant Plasmodium falciparum vaccine candidate, in adults.

In a randomized single-blind study, 13 healthy adult volunteers were subcutaneously immunized with 2 or 3 single 50 or 400 micrograms doses of a Plasmodium falciparum recombinant vaccine candidate designated 5.1-[NANP]19. The vaccine caused transitory reactions at the injection site.

Blockade of physiologically secreted IFN-gamma inhibits human T lymphocyte and natural killer cell activation.

The role of physiologically secreted human IFN-gamma in T lymphocyte and NK cell activation has been probed with a panel of mouse mAb directed against various epitopes of the human IFN-gamma molecule, or human IFN-gamma R. Addition to the culture medium of those mAb that neutralize the antiviral activity of IFN-gamma or interact with its receptor inhibited proliferative and cytotoxic responses elicited in PBL by HLA alloantigens, anti-CD3 mAb, and IL-2, but not the proliferative response to PHA. The IFN-gamma blockade also inhibited IFN-gamma, IL-2, and TNF-alpha release during MLC.

A naturally occurring gene encoding the major surface antigen precursor p190 of Plasmodium falciparum lacks tripeptide repeats.

Plasmodium falciparum merozoites have variable surface proteins that are processed from a 190-kd precursor protein (p190). The gene encoding p190 exists in two allelic forms and cross-over events occurring mainly near the 5' end, combined with isolate-specific tripeptide repeats, contribute to its antigen diversity. We have sequenced a large portion of the p190 gene from the parasite isolate RO-33 (Ghana).

Plasmodium falciparum-specific human T cell clones: recognition of different parasite antigens.

T lymphocyte clones specific for malarial (Plasmodium falciparum) blood stage antigens were obtained from acutely infected patients or from donors living in a malaria-endemic area of West Africa. Thirty-four clones carrying the CD4 antigen, and one CD8+ clone, were tested in a proliferation assay for their capacity to recognize P. falciparum isolates of different geographical origins.

A labour-saving method for the in vitro culture of Plasmodium falciparum.

The in vitro cultivation of Plasmodium falciparum requires at least daily changes of medium (Trager and Jensen, 1976). Addition of 50 mg per litre of hypoxanthine to medium RPMI 1640 permits to postpone the change of medium for up to 72 hours. A single subculture step is required to remove unlabelled hypoxanthine prior to the use of the cultured material in 3H-hypoxanthine incorporation assays.

[A case of chloroquine-resistant tropical malaria from eastern Africa (Kenya)].

A case of chloroquine-resistant falciparum malaria in a non-immune Swiss tourist is described. The infection was acquired in Kenya in spite of regular chloroquine prophylaxis with therapeutic serum levels. The isolated plasmodia showed marked in vitro resistance to chloroquine and sensitivity to mefloquine and pyrimethamine.

Note on the stability of mefloquine hydrochloride in aqueous solution.

Using Desjardins' technique for the testing of antimalarials against Plasmodium falciparum in vitro, a 4-year-old solution of mefloquine in water (10(-3) mol/litre) was compared with a freshly prepared solution.The results showed that the two solutions had almost identical activity. There was no evidence for any instability of mefloquine in aqueous solution.