Immunological processes in malaria pathogenesis

Malaria is possibly the most serious infectious disease of humans, infecting 5-10% of the world's population, with 300-600 million clinical cases and more than 2 million deaths annually. Adaptive immune responses in the host limit the clinical impact of infection and provide partial, but incomplete, protection against pathogen replication; however, these complex immunological reactions can contribute to disease and fatalities. So, appropriate regulation of immune responses to malaria lies at the heart of the host-parasite balance and has consequences for global public health. This Review article addresses the innate and adaptive immune mechanisms elicited during malaria that either cause or prevent disease and fatalities, and it considers the implications for vaccine design.     

Forecasting and prevention of epidemic malaria: new perspectives on an old problem

There is a clear need for improved epidemic malaria surveillance mechanisms in areas prone to the disease. Epidemiological surveillance systems are rarely able to provide information in a sufficiently timely manner for adequate epidemic response. This is especially true in African countries where surveillance is poorly developed, and particularly so in remote regions of unstable malaria such as desert fringes. There is long standing evidence linking climatic variability and epidemic risk. The last ten years have seen significant developments in Environmental Information System (EIS) for a range of natural resource management purposes. The routine information products from these systems have been shown to be both spatially and temporally related to malaria transmission indicators across the African continent. EIS may therefore provide a useful and cost effective input to epidemic malaria control planning and response.     

Ancient DNA studies: new perspectives on old samples

In spite of past controversies, the field of ancient DNA is now a reliable research area due to recent methodological improvements. A series of recent large-scale studies have revealed the true potential of ancient DNA samples to study the processes of evolution and to test models and assumptions commonly used to reconstruct patterns of evolution and to analyze population genetics and palaeoecological changes. Recent advances in DNA technologies, such as next-generation sequencing make it possible to recover DNA information from archaeological and paleontological remains allowing us to go back in time and study the genetic relationships between extinct organisms and their contemporary relatives. With the next-generation sequencing methodologies, DNA sequences can be retrieved even from samples (for example human remains) for which the technical pitfalls of classical methodologies required stringent criteria to guaranty the reliability of the results. In this paper, we review the methodologies applied to ancient DNA analysis and the perspectives that next-generation sequencing applications provide in this field.     

Immunological studies in pre-eclamptic toxaemia.

Although five patients with severe pre-eclamptic toxaemia (PET) had increased anticomplementary activity in their serum, there was no evidence of complement activation in the plasma of four of the five patients. These results are not implicated in the pathogenesis of PET. No significant correlation was found between anticomplementary activity and pregnancy-associated alpha2-glycoprotein.     

Immunological studies of acetylcholine receptors

Immunochemical techniques for the study of acetylcholine receptors are described. Immunization of rabbits, rats, guinea pigs, and goats with acetylcholine receptor protein purified from Electrophorus electric organ tissue results in muscular weakness and death due to impaired neuromuscular transmission. Serum from immunized animals contains high concentrations of antibodies directed at receptors from the electric organ and low concentrations of antibodies directed at receptors from skeletal muscle. The detailed similarities between the disease of receptor-immunized animals, “experimental autoimmune myasthenia gravis” (EAMG), and myasthenia gravis are compared. Reactions of antisera from animal with EAMG with receptor from Electrophorus and Torpedo are studied. Antireceptor antibodies in these antisera are directed predominantly at determinants other than the acetylcholine-binding site.     

Opportunities, problems and perspectives for malaria control in sub-Saharan Africa

Environments conducive to high malaria transmission and widespread poverty are at the roots of the 'malaria giant', which affects 46 countries in Africa. The recent interest in and momentum of work on malaria, in endemic countries and the international community, is unprecedented and opens new perspectives for controlling the disease. Significant steps included: (i) the allocation of US$20 million by WHO for accelerated implementation of malaria control in 34 African countries in 1997-98; (ii) the Declaration on Malaria by the Heads of States of the Organization of African Unity and the establishment of the African Initiative for Malaria Control in 1997; (iii) the concomitant mobilisation of the research community in the Multilateral Initiative on Malaria; (iv) the G8 Summit in 1998 in Birmingham asking for higher commitment to malaria control, particularly in Africa; and (v) the Roll Back Malaria initiative set as a WHO priority project in 1998. However, experiences have proved the alarming 'resilience' of the malaria system in Africa, showing devastating consequences when malaria returns to the original levels after intensive control is interrupted. Effective malaria control in Africa requires long-term action, firmly rooted in the social development of the country.