EM IN BIOLOGICAL SCIENCES IN CUBA

Cuba is well know for its science tradition in Medicine, with a history spanning from the introduction in 1804 of the first vaccination procedure in Havana by Tomás Romay, the foundation of the Academy of Sciences in 1831, and the theory of transmission of yellow fever by mosquitos, proposed by Carlos J. Finlay in 1881, to it's most recent accumulation of basic and clinical information regarding biomedicine-related products.

Electron microscopy (EM) in biomedical sciences begun in Cuba in the 60's at the National Institute of Oncology and Radiobiology (INOR), and the National Center for Scientific Research (CNIC). Soon after this, a research group at the Hermanos Ameijeiras Hospital in Havana also started working on the subject. In the early days the main focus was on the studies related to human, animal and plant diseases. As examples of this initial work, malignant lymphoma cells were ultra structurally characterized at INOR, and the diagnosis of aviar laringo traqueitis versus Newcastle viruses in an epidemic that affected most of the chicken population in Santa Clara, was done at CNIC.

A big impulse was given to EM in the eighties and nineties with the development of different laboratories within the new scientific centers such as CENSA, and CIGB, among others.The West of Havana Scientific Pole, a highly interactive conglomerate of biomedical, agriculture and veterinary institutions, functions as a means to speed up research and development in these fields. An important number of these institutions actively work in basic, clinical, and applied human and veterinary immunology. Among these are: the Center for Molecular Immunology, the Finlay Institute, the Center for Genetic Engineering and Biotechnology, the International Neurological Restoration Center, the Medical and Biology Faculties of Havana University, the Center for Immunoassays, the National Center of Bioreagents, the National Center for the Production of Laboratory Animals, the Institute of Hematology and Immunology, the National Institute of Oncology and Radiobiology, the "Pedro Kourí" Tropical Medicine Institute, the Center for Biological Research, the National Reference Laboratory for AIDS, and the National Center for Animal Health.

EM IN RECENT BIOMEDICINE:

Studies conducted with products developed and now registered in the Cuba and other countries, as natural and recombinant alpha and gamma interferons, transfer factor, recombinant interleukin-2, the first effective natural vaccine for meningococcus type B, a recombinant vaccine for Hepatitis B produced in yeast cells, monoclonal antibodies for cancer diagnostics and and the treament of organ transplant rejection, and a myriad of diagnostic systems for infectious and chronic diseases, including Hepatitis B and C, Dengue, HIV, HTLV-I/II, celiac disease, etc., have allowed not only to access to an enormous volume of scientific information, but also have had a profound impact in many health indicators. In many of these results, Electron Microscopy has played a very important role, providing data and information not only during Research, but also in Development, and Quality Control. Electron Microscopy is also involved in many investigations under development.

Some results of Cuban Biomedicine where EM has played and important role are:

  • Development of natural and recombinant alpha and gamma Interferons, Transfer Factor, rec IL 2
  • Development of the first effective natural vaccine against B meningitis
  • Development of a recombinant vaccine for Hepatitis B
  • Development of therapeutic monoclonal antibodies
  • Development of diagnostic antigens for Hepatitis B and C, Chagas, Dengue, HIV-AIDS, HTLV-I/II, celiac disease, syphylis, etc

Some examples of current research where EM is involved are:

  • Synthetic, natural, and recombinant prophylactic vaccines against Haemophilus influenzae B, Dengue, Cholera
  • Therapeutic vaccines for Cancer, HIV, and Hepatitis C/B
  • Recombinant antibodies for the treatment of Cancer and Autoimmune Diseases
  • Recombinant proteins, peptides, and other biopharmaceuticals
  • Human and veterinary diagnostic systems
  • Natural and recombinant veterinary vaccines
  • Transgenic plants as bioreactors for biopharmaceuticals
EM IN AGRICULTURE:

EM is also used as an essential tool in research related to plants, and agriculture, from studies related to disease resistance, pathogen diagnostics, physiopathology, biotechnology, and others uses. In cultivars of importance as beans, potato, soy, sugar cane, and tomato, EM has been fundamental to diagnose, characterize, and study alterations caused by cell viruses, as the common bean mosaic virus, the severe cawpea mosaic, the potato X virus, the sugar cane mosaic virus, and the tomato mosaic virus, among others. EM has also contributed to gather information for the first time in the country about numerous microorganisms, as the sugar cane bacillus-like virus, the papaya apical nercrosis virus, and a phytoplasm related to the sugar cane yellow leaf syndrome.
Physiopathologic studies of the host-pathogen interaction have been carried out in the cases of the fungus Ustilago scitaminea, that affects the sugar cane. Proteins related to the defensive response of the plant produced after this infection have been identified using immuno-electron microscopy techniques (IEM).
Ultrastructure has also been a key element in the analysis of bioproducts derived from entomopathogenic fungi, as Metharhizium anisopliae and Beauveria bassiana, that are employed in the biological control of insect plagues.
Pathogenic bacteria as Xanthomas albilineans, X. campestri and Leifsonia xili have also been studied by EM, and IME has been used as a confirmatory technique in the classification of the nitrogen fixing bacterium Azospirillum brasilense, that is benefitious for many cultivars. Among the physiologic plant processes that have been analyzed by EM we can mention cell proliferation in sugar cane meristems, where a description of the ultrastructural changes of such cells, of nuclear bodies of importance to the vital processes, and a characterization of the different phases of the cells during tissue culture have been documented.
EM IN PHYSICAL SCIENCES IN CUBA

Electron microscopy in physical sciences begun in Cuba in the early 70's at the National Center for Scientific Research (CNIC). Soon after this, research groups at the University of Havana also started working on the subject. In the early days the main focus was on metals, alloys, and ceramic materials, and a number of projects started oriented towards the defect analysis of metals used in the heavy industry in Cuba. As an example of this earlier work, the analysis of the blades used in the sugar cane cutting machines resulted in important modifications of the processing procedure of the alloys used.
A big impulse was given to EM in the eighties and nineties. Work started on magnetic materials for permanent magnets with systematic studies in the relation between microstructure and properties. This resulted in an important number of publications in international peer-reviewed journals. At the same time, projects in high Tc superconductors, and giant magnetoresistance materials were also developed, which led to important published results. In colaboration with the UFRGS in Brasil, an important contribution was done to the understanding of the influence of the microstructure in the magnetoresistance mechanism of CoCu alloys, which draw attention to the overlooked fact that spinodal decomposition could be playing a determinant role in the transport properties of this system.
In 2003 a National Science Academy Award was given the group of Dr. Ernesto Estevez Rams which emcompassed most of the microscopy work done in magnetic materials in the last years.