Parasitology(Helminthology)
TABLE OF CONTENTS PAGES
INTRODUCTION……………………………………………………………………………. 2
LIFE CYCLE OF Loa loa ……………………………………………………………...4
PATHOLOGY of Loa loa …………………………………………………………………… 6
IMMUNE RESPONSE AND MOLECULAR BIOLOGY OF Loa loa………………... 9
CONCLUSION………………………………………………………………………………...11
REFERENCES
TERM PAPER
TOPIC: PATHOLOGY , IMMUNE RESONSE AND MOLECULAR BIOLOGY OF Loa loa . INTRODUCTION
Loa loa is a filarial parasite transmitted by tabanid female flies of the genus Chrysops (C silacea and C dimidiate). The incidence of infection within endemic region of the central and west African rain forest is high with 20-40% of the population being microfilaraemic , and about twice as many habouring adult worms without showing patent microfilaraemia (Dupont et al.,2007). The adult worms actively migrate through subcutaneous tissues at rates of up to 1cm/ min. Female Loa loa measures 50- 70mm in length and 0.5mm in diameter, while the males measures 30 -35mm in length and 0.4mm in diameter. The microfilariae forms, measures 290-300µm by 6-8µm in size. During infection the microfilariae forms are released into the blood stream, where they become numerous between 10a m and 2pm(diurnal periodicity). Moreso, the presence of the sheath and three or more terminal nuclei distinguish the microfilariae of L. loa from other blood –borne microfilariae. ( Strickland, 2000)
Transmission is by day –biting female tabanid flies, which pick up the microfilaria of L loa during blood meals . The injested
INTRODUCTION……………………………………………………………………………. 2
LIFE CYCLE OF Loa loa ……………………………………………………………...4
PATHOLOGY of Loa loa …………………………………………………………………… 6
IMMUNE RESPONSE AND MOLECULAR BIOLOGY OF Loa loa………………... 9
CONCLUSION………………………………………………………………………………...11
REFERENCES
TERM PAPER
TOPIC: PATHOLOGY , IMMUNE RESONSE AND MOLECULAR BIOLOGY OF Loa loa . INTRODUCTION
Loa loa is a filarial parasite transmitted by tabanid female flies of the genus Chrysops (C silacea and C dimidiate). The incidence of infection within endemic region of the central and west African rain forest is high with 20-40% of the population being microfilaraemic , and about twice as many habouring adult worms without showing patent microfilaraemia (Dupont et al.,2007). The adult worms actively migrate through subcutaneous tissues at rates of up to 1cm/ min. Female Loa loa measures 50- 70mm in length and 0.5mm in diameter, while the males measures 30 -35mm in length and 0.4mm in diameter. The microfilariae forms, measures 290-300µm by 6-8µm in size. During infection the microfilariae forms are released into the blood stream, where they become numerous between 10a m and 2pm(diurnal periodicity). Moreso, the presence of the sheath and three or more terminal nuclei distinguish the microfilariae of L. loa from other blood –borne microfilariae. ( Strickland, 2000)
Transmission is by day –biting female tabanid flies, which pick up the microfilaria of L loa during blood meals . The injested
References: Baize ,S, Wahl, G, Soboslay,PT, Egwang,TG, and Georges,AJ, (1997). T helper responsiveness in human Loa loa infection; defective specific proliferation and cytokine production by CD4+ T Couissinier – Paris ,P, and Dessein ,AJ, (1995). Schistosomal –specific helper T cell clones from subjects resistant to infection by Schistosoma mansoni are Th0/2 Immunology 25:2295-302 Dupont , A, Zue-N’dong , J, and Pinder, M, (2007) Loaloa filariasis within the endemic region. Trans R soc Trop. Med Hyg, 82:730 John, MG, and Wayne, M, (2005) John Wiley and Sons, New York Karita ,H, Taru ,M, and Sakari ,JT, (2010) Maizels , RM, Bundy ,DAP, Selkirk, ME, Smith, DF, Anderson ,RM,( 2008). Immunological modulation and evasion by helminthes parasites in human populations Oyerinde, JPO, (1999). The filarial worm,pp 256-257. Essential of Tropical Medical Parasitology , 1st (ed) University of Lagos Press. Piessens ,WF, and Partono , F, (2007). Host-vector –parasite relationships in human filariasis. Semin Infect Dis 3:131-5 Pinder , M, Dupont, A, Egwang ,TG, (1990) . Identification of a surface on Loaloa microfilariae the recognition of which correlates with the amicrofilaremic state in man .Journal Immunology 141:2480-6 Ralph , C, and Eagle(Jr), MD, (2010) Wills Eye Hospital Strickland, GT, (2000)