The malaria vaccine: seventy years of the great immune hope.

The cluster of seminal microbiological discoveries at the end of the 19th century through to the first quarter of the 20th century gave rise to the expectation that the control of malaria would be by scientific technology (as opposed to the 'brute force' of bonification/massive engeneering works) and that technology would be immunization by a malaria vaccine. Immunology's foundation was in microbiology and the two related disciplines matured concurrently. Immunization with dead or inactivated microorganisms became immunology's strongest arm, affording protection against many major diseases such as smallpox, anthrax, rabies, yellow fever and tetanus.

Serological cross-reactivities between the retroviruses HIV and HTLV-1 and the malaria parasite Plasmodium falciparum.

Serum samples from three populations of Papua New Guinea, where Plasmodium falciparum malaria and human T-lymphotropic virus type 1 (HTLV-1) are coendemic at high prevalence rates, showed statistically significant ELISA co-seropositivity and co-seronegativity. Cross-reactivity was further indicated by the presence of 10 bands ranging from 134 kDa to 18 kDa on immunoblots of electrophoresed whole lysate P. falciparum antigen against serum of HTLV-1 seropositive patients from an area where malaria is not present.

Immunoblot characterization of IgG, IgM and IgE antibodies elicited during the course of fatal and non-fatal infections of Plasmodium berghei in DBA/2 and Balb/c mice.

When infected with the CRS line of Plasmodium berghei ANKA, DBA/2 mice died of a fulminating infection around day 20 post-infection whereas Balb/c mice had crises around day 15 then low or subpatent parasitaemias until approximately day 73, when sterile immunity is believed to have supervened. Immunoblots for parasite-specific immunoglobulins G, M and E were made from the sera taken during the course of infection in each mouse strain. Although both strains elicited antibodies to a 128-kDa antigen by day 8, this was solely of the IgG class in the DBA/2 but of both IgG and IgM in the Balb/c.

Immunoglobulin complex deposits in Plasmodium falciparum-infected placentas from Malawi and Papua New Guinea.

Term placentas from 35 patients infected with Plasmodium falciparum were obtained in Malawi in southeast Africa and six term placentas from patients infected with P. falciparum were obtained in Wewak, Papua New Guinea, Melanesia. The placental tissues were examined by light microscopy and by an immunohistologic method to compare the pathologic changes of placentas in the two malaria-endemic countries.

Plasmodium falciparum-specific immunoglobulin G (IgG), IgM, and IgE antibodies in paired maternal-cord sera from east Sepik Province, Papua New Guinea.

Enzyme-linked immunosorbent assay (ELISA) and Western blot (immunoblot) serological analyses for immunoglobulin G (IgG), IgM, and IgE antibodies to Plasmodium falciparum were made from 46 maternal-cord serum pairs obtained from parturient East Sepik (Papua New Guinea) women and their newborn. Concurrent study of these women had shown that placental parasitemia rates were related to parity with the highest rate (41%) in the primiparous group and the lowest rate (3%) in the women who had given birth more than three times (> 3 parity group). Overall ELISA positivity rates for antimalarial IgG, IgM, and IgE antibodies in the maternal sera were 54.

Bancroftian filariasis in an isolated hunter-gatherer shifting horticulturist group in Papua New Guinea.

A survey for Wuchereria bancrofti microfilaraemia using membrane filtration was carried out among the Hagahai, a recently contacted Papua New Guinea group of hunter-gatherer shifting horticulturists. Adult men had a significantly higher microfilaraemia rate than women. Children aged > 15 years had significantly fewer infections than adults and the microfilaraemia densities were considerably lower.

Prenatal immune hypersensitization to malaria: Plasmodium falciparum-specific IgE antibody in paired maternal and cord sera from Papua New Guinea.

In a study of malaria and pregnancy in East Sepik Province of Papua New Guinea 45 maternal and cord serum pairs were tested for Plasmodium falciparum-specific IgE antibody. There were 17 positive sera: 6 cases of maternal serum alone, 5 cases of cord serum alone and 3 pairs of maternal and cord sera. IgE antibody positivity rates in the mothers increased with parity, whereas placental parasitaemia rates decreased.

Placental pathology in Plasmodium berghei-infected rats.

The pathologic changes in placentae of pregnant rats infected with Plasmodium berghei at different stages of gestation were studied using light and electron microscopy and immunohistochemistry. The major changes observed were thickening and duplication of the trophoblastic basement membrane, and accumulation of parasitized erythrocytes and occasional mononuclear cells in the maternal blood space. Immunohistochemical examination of nine placentae revealed that six stained positively for IgG, two for IgM, and four for P.

Placental Plasmodium falciparum parasitaemia in East Sepik (Papua New Guinea) women of different parity: the apparent absence of acute effects on mother and foetus.

The effects of malaria were studied in a group of parturient women of East Sepik Province, Papua New Guinea. Further information was gathered from a search of hospital records and interviews with village aid post orderlies. Examination of placental blood revealed a Plasmodium falciparum parasitaemia rate of 41% of the primiparae, 23% in parous 2, 25% in parous 3, and 3% in multiparae greater than 3.

HTLV-I antibody studies in villagers in East Sepik Province, Papua New Guinea.

Serum samples collected in 1984 during a malariometric survey of two villages in the East Sepik Province of Papua New Guinea were tested for antibodies to HTLV-I. None of the villagers showed any symptoms suggestive of retrovirus infection. Eighteen of the 186 (9.

Characterization of a model of malaria in the pregnant host: Plasmodium berghei in the white rat.

This study characterizes a Plasmodium berghei white rat model of P. falciparum malaria in the pregnant human. Seventy-day-old and 114-day-old female rats, given an infecting inoculum at time of mating, had higher parasitemias and a more severe anemia than age- and sex-matched controls.

Plasmodium-specific immunoglobulin E in sera from an area of holoendemic malaria.

Serum samples obtained from adults living in an area of holoendemic malaria in Papua New Guinea and from control residents of Hawaii were tested for Plasmodium-specific immunoglobulin (Ig) E antibody by the enzyme-linked immunosorbent assay. Fifteen (33.3%) of the New Guinea sera had absorbance values indicative of seropositivity.

Prenatal immune priming in malaria: antigen-specific blastogenesis of cord blood lymphocytes from neonates born in a setting of holoendemic malaria.

The Plasmodium falciparum-specific blastogenic response of cord blood lymphocytes (CBLs) from neonates born in an area of holoendemic malaria of Papua New Guinea was compared to that of CBLs from neonates born in Hawaii, where malaria transmission does not occur. The average blastogenesis stimulation index of the New Guinea CBLs was 4.5 times greater than that of the Hawaiian group of samples.