What is amastigote and Promastigote?
Once inside the macrophage, the promastigote differentiates from a motile promastigote form, which has a long flagellum and an elongated cell shape, to an amastigote form that has a short flagellum with only a small bulbous tip extending beyond a now more spherical cell body.
What are the Leishmania species?
Leishmaniasis comes in three forms: cutaneous, visceral, and mucocutaneous. Different species of the Leishmania parasite are associated with each form. Experts believe that there are about 20 Leishmania species that can transmit the disease to humans.
What is Leishmania spp amastigote?
The amastigotes are small spherical non-flagellated cells ranging from 2-4µm in diameter. The nucleus and kinetoplast are surrounded by small ring of vacuolated cytoplasm and the cells are among the smallest nucleated cells known.
How can you tell Leishmania species?
PCR hybridization is one of the first molecular methods for species identification and genotyping. DNA probes have been designed for Leishmania species identification. The most common target used for Leishmania spp identification is kDNA. DNA probes targeting kDNA have been applied for L.
Which form of Leishmania is found in man?
Leishmania donovani is a species of intracellular parasites belonging to the genus Leishmania, a group of haemoflagellate kinetoplastids that cause the disease leishmaniasis. It is a human blood parasite responsible for visceral leishmaniasis or kala-azar, the most severe form of leishmaniasis.
What causes leishmania?
The most common forms are cutaneous leishmaniasis, which causes skin sores, and visceral leishmaniasis, which affects several internal organs (usually spleen, liver, and bone marrow).
What is cutaneous leishmaniasis?
Cutaneous leishmaniasis is the most common form of leishmaniasis. It is caused by over 15 different species of the protozoan parasite Leishmania, transmitted by infected female sandflies. Although cutaneous leishmaniasis is not life-threatening, it can have devastating effects on local communities.
Why is species identification important in the diagnosis of Leishmania infection?
The ability to distinguish between Leishmania species is crucial for differentiation of various forms of disease (visceral, cutaneous, mucocutaneus) at least in humans in order to establish correct diagnosis and prognosis of the disease as well as to support decision-making regarding application of the appropriate …
What happens to the promastigotes in leishmaniasis?
Promastigotes transform in these cells into the tissue stage of the parasite (i.e., amastigotes) , which multiply by simple division and proceed to infect other mononuclear phagocytic cells . Parasite, host, and other factors affect whether the infection becomes symptomatic and whether cutaneous or visceral leishmaniasis results.
Where are Leishmania amastigotes found in the body?
Leishmania amastigotes. Amastigotes of Leishmania are spherical to ovoid and measure 1-5 µm long by 1-2 µm wide. They possess a large nucleus, a prominent kinetoplast, and a short axoneme, the last of which is rarely visible by light microscopy. The organisms reside in macrophages of the host and can be found throughout the body.
What are the two types of Leishmania protozoa?
The morphology of Leishmania protozoa varies by species and throughout the life cycle. Leishmania is able to exist in two forms: amastigote when it is in the human host (intracellular), and promastigote when it exists in the vector (extracellular).
How does an infected sandfly become a promastigote?
Life Cycle. Sandflies become infected by ingesting infected cells during blood meals (, ). In sandflies, amastigotes transform into promastigotes, develop in the gut (in the hindgut for leishmanial organisms in the Viannia subgenus; in the midgut for organisms in the Leishmania subgenus), and migrate to the proboscis .
