In vitro quantitation of Theileria parva sporozoites for use - TropMed ...

Chapter 6: Storage of Theileria parva stabilates at 4°C and -20°C 85
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1
0.9
Predicted proportion of positive wells
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0
-8 -7 -6 -5 -4 -3
Dose (ln t.e.)
Figure 14: Titration curves of Katete-K2g () and K2s (-----) stabilates stored on ice for 0
(control), 6, 12 and 24 h (from left to right). [ln t.e.] is the natural log of the stabilate dose
expressed in tick equivalents. Individual graphs and data points illustrated in Appendix IX.
Infectivity losses of glycerol and sucrose stabilates (K2g and K2s) in function of time of storage at -20ºC
Sucrose stabilates retained only 2.3, 2.7 and 0.7% of the infectivity of control stabilate after 1, 2 and
4 weeks of storage respectively (Figure 16). The effect of storage time on infectivity was significant
at all storage periods (P