Hella cell line belongs to -

Ans. is 'c' i.e., Continuous cell line Cultivation of viruses* As viruses are obligate intracellular parasites they cannot be grown on any inanimate culture medium(AI05).* Three methods are employed for cultivation of viruses :1. Animal Inoculation# Mice are most widely employed animals. Other animals used are guinea pigs, rabbits and ferrets.* Usually adult mice are used. But for coxsackie virus, suckling mice are used as adult mice is not susceptible.2. Embryonated eggs# Sites of inoculation are :a) Chorioallantoic Membrane - visible pocks are produced -> HSV, Vaccinia, Small pox, Monkey pox, Cow pox, Camel pox.b) Amniotic Sac - Influenza, mumps.c) Allantoic Cavity - Influenza, Some paramyxovirusesd) Yolk Sac - Some viruses, Chlamydia, Rickettsia3. Tissue culture# Most important method for virus isolation.# Three types of tissue culture are availablei) Organ Cultureii) Explant Cultureiii) Cell Culture - (routinely employed)Cell culture* It is the most commonly employed method for virus isolation. It is of following types1) Primary cell culture: Cannot be maintained in serial cultures. Examples are Rhesus monkey kidney, Human amnion, chick embryo fibroblast and human embryonic kidney.2) Diploid cell strains : Can be maintained in serial culture for a limited number of times (about 50 passages). Example are WI-38, HL-8 and human diploid fibroblast.* Human diploid fibroblasts (HDF) cell line is used for cultivation of coxsackie A7, 9, 16; CMV;Echovirus; enteroviruses; HSV-1, 2; Poliovirus; parainfluenza virus, rhinovirus and VZV.3) Continuous cell line : Can be maintained in serial culture indefinitely. Examples are Hela, HEP-2, McCoy, vero cells, BHK and Detroid-6.