Pre-treatment of canine plasma with heat, rather than acid, efficiently enhances Dirofilaria immitis antigen detection

Table 2 OD values from twofold serial dilutions of positive plasma sample (control) and four ICD protocols

Dilution	No treatment		ICD-1			ICD-2			ICD-3			ICD-4
Dilution	OD ± SD	Color	OD ± SD	P***	Color	OD ± SD	P	Color	OD ± SD	P	Color	OD ± SD	P	Color
2¹	0.435 ± 0.066*	+ **	0.525 ± 0.039	0.02	+	0.624 ± 0.017	10⁻⁴	+	0.392 ± 0.020	0.22	+	0.534 ± 0.026	0.01	+
2²	0.385 ± 0.063	+	0.472 ± 0.065	0.02	+	0.568 ± 0.033	10⁻⁴	+	0.285 ± 0.041	0.01	+	0.446 ± 0.023	0.07	+
2³	0.279 ± 0.021	+	0.510 ± 0.015	10⁻⁴	+	0.513 ± 0.006	10⁻⁴	+	0.292 ± 0.005	0.54	+	0.377 ± 0.008	10⁻³	+
2⁴	0.184 ± 0.004	+	0.436 ± 0.006	10⁻⁴	+	0.441 ± 0.027	10⁻⁴	+	0.299 ± 0.019	10⁻⁴	+	0.250 ± 0.013	10⁻⁴	+
2⁵	0.128 ± 0.013	+	0.318 ± 0.011	10⁻⁴	+	0.334 ± 0.002	10⁻⁴	+	0.118 ± 0.037	0.19	+	0.192 ± 0.014	10⁻⁴	+
2⁶	0.069 ± 0.002	+	0.190 ± 0.015	10⁻⁴	+	0.215 ± 0.011	10⁻⁴	+	0.080 ± 0.017	0.07	+	0.099 ± 0.002	10⁻⁴	+
2⁷	0.031 ± 0.003	+	0.085 ± 0.018	10⁻⁴	+	0.121 ± 0.006	10⁻⁴	+	0.053 ± 0.006	10⁻³	+	0.046 ± 0.008	10⁻²	+
2⁸	0.011 ± 0.005	−	0.044 ± 0.017	10⁻⁴	+	0.042 ± 0.004	10⁻⁴	+	0.018 ± 0.004	0.06	−	0.020 ± 0.001	0.02	−
2⁹	0.006 ± 0.002	−	0.019 ± 0.006	10⁻³	+	0.011 ± 0.003	0.04	+	0.003 ± 0.002	0.27	−	0.006 ± 0.003	0.94	−
2¹⁰	0.007 ± 0.002	−	0.006 ± 0.005	0.83	−	0.007 ± 0.003	0.98	−	0.011 ± 0.008	0.37	−	0.006 ± 0.000	0.73	−
2¹¹	0.004 ± 0.002	−	0.002 ± 0.002	0.22	−	0.005 ± 0.003	0.58	−	0.002 ± 0.002	0.14	−	0.010 ± 0.001	10⁻²	−
2¹²	0.006 ± 0.002	−	0.004 ± 0.001	0.45	−	0.003 ± 0.003	0.28	−	0.003 ± 0.002	0.37	−	0.013 ± 0.003	0.09	−

^*The optical density values are expressed as mean ± standard deviation (SD)
^**The color change based on the DiroCheck is read as + (positive) or – (negative)
^***P value was calculated by comparing the OD values between NO Treatment group and ICD-1, ICD-2, ICD-3, or ICD-4

ISSN: 1756-3305