Heat fixation inactivates viral and bacterial pathogens and is compatible with downstream MALDI mass spectrometry tissue imaging

Table 1 Viable virus determination from untreated and heat fixed VEEV (vaccine strain and virulent strain) infected tissue

Pathogen	Tissue	Weight (mg)	Treatment	Dilution and plaque count						Average titer (pfu/ml)
Pathogen	Tissue	Weight (mg)	Treatment	10 ⁻¹	10 ⁻²	10 ⁻³	10 ⁻⁴	10 ⁻⁵	10 ⁻⁶	Average titer (pfu/ml)
VEE (TC83) vaccine strain	brain	100	none	100+	21	3	0	0	0	2.5E + 04
		120	none	100+	30	8	0	0	0	5.5E + 04
		140	HF	0	0	0	0	0	0	0.0E + 00
		125	HF	0	0	0	0	0	0	0.0E + 00
	spleen	47	none	0	0	0	0	0	0	0.0E + 00
		52	none	0	0	0	0	0	0	0.0E + 00
		55	HF	0	0	0	0	0	0	0.0E + 00
		50	HF	0	0	0	0	0	0	0.0E + 00
VEE (Trinidad donkey) virulent strain	brain	210	none	TNTC	TNTC	TNTC	TNTC	TNTC	42	4.2E + 08
		240	none	TNTC	TNTC	TNTC	TNTC	58	14	9.9E + 07
		220	none	TNTC	TNTC	TNTC	TNTC	TNTC	37	3.7E + 08
		190	none	TNTC	TNTC	TNTC	TNTC	TNTC	34	3.4E + 08
		190	HF	0	0	0	0	0	0	0.0E + 00
		180	HF	0	0	0	0	0	0	0.0E + 00
		260	HF	0	0	0	0	0	0	0.0E + 00
		210	HF	0	0	0	0	0	0	0.0E + 00
	spleen	60	none	TNTC	TNTC	42	7	0	0	2.5E + 06
		50	none	45	13	0	0	0	0	8.8E + 03
		50	none	39	11	0	0	0	0	7.5E + 03
		70	none	38	9	0	0	0	0	6.5E + 03
		50	HF	0	0	0	0	0	0	0.0E + 00
		60	HF	0	0	0	0	0	0	0.0E + 00
		50	HF	0	0	0	0	0	0	0.0E + 00
		70	HF	0	0	0	0	0	0	0.0E + 00

ISSN: 1471-2180