Triiodothyronine (T3)

T3 Antibody

Name	Triiodothyronine (T3) antibody
Catalog #	R515n5	R514n5		R513c8
Type	Rabbit monoclonal antibody
React Species	Human
Platforms	Chemiluminescence Immunoassay (CLIA)		Immunochromatography assay (ICA)
Matched Pair	R515n5 (Capture) - R514n5 (Detection) R515n5 (Capture) - R513c8 (Detection)		R513c8 (Capture) - R515n5 (Detection)
Purity	Purity>95%, purified by Protein A/G chromatography
Buffer	1 x PBS, pH 7.4
Storage	Aliquot and store at -20°C or lower. Avoid freeze / thaw cycles.

Labeled & Conjugated antibody

Name	Catalog #	Conjugate	Matched Pair	Platform	Methodology
T3 Antibody	L344h1	AE	L343h1 (Capture) - L344h1 (Detection)	Chemiluminescence Immunoassay (CLIA)	Sandwich
T3 Antibody	L343h1	Biotin	L343h1 (Capture) - L344h1 (Detection)	Chemiluminescence Immunoassay (CLIA)	Sandwich

OEM Reagents

Name	Catalog #	Platform	Methodology
fT3 Reagents	Q120k1	Chemiluminescence Immunoassay	Sandwich

Product Information

Antibody Affinity

T3 antibodies R513c8, R514n5, and R515n5 were detected via ELISA platform using the T3 antigen with EC50s of 6.86, 7.71, and 50.8 ng/mL, respectively.

Direct Chemiluminescent Immunoassay (CLIA) platform

Roche-assigned fT3/tT3 clinical samples were detected using the R515n5 (Capture)-R514n5 (Detection) antibody pair. The T3 Sandwich antibodies (R515n5, R514n5) on the direct Chemiluminescent Immunoassay (CLIA) platform demonstrated a 10 times higher signal-to-noise ratio (S/N) compared to the Competitive Immunoassay. The fT3 detection sensitivity achieved is 0.1 pmol/L, and a strong correlation (R² > 0.99) was confirmed between the detection results and Roche-assigned samples.

fT3 Lowest Detection Limit

Calibrator	Concentration（pmol/L）	RLU Avg.	Curve
S1	0	5407	y=38133x+5407
S2	3.3	131246
20 times RLU Avg.（Blank）		5549
SD		143.2
Average Value +2SD		5836
Lowest Detection Limit (pmol/L)		0.011

fT3 Sample Coincidence Rate

Sample	Concentration (pmol/L)	RLU
1	0.000	5407
2	3.32	131246
3	7.15	265489
4	18.63	856983
5	30.12	1656988
6	49.55	2556942

Table 1. fT3 Clinical comparison analysis data on CLIA

Figure 4. fT3 Standard curve on CLIA

tT3 Sample Coincidence Rate

Sample	Concentration (pmol/L)	RLU
1	0.000	3407
2	0.40	90705
3	1.00	244456
4	2.48	1094240
5	4.94	3139387
6	10.12	7028859

Table 2. tT3 Clinical comparison analysis data on CLIA

Figure 5. tT3 Standard curve on CLIA

Cross Reactivity

L-T4 at 500ng/mL was measured via T4 sandwich antibodies (R515n5, R514n5), and the cross-reactivity was 0.01%.

Time-resolved Fluorescent Immunoassay (TRFIA) platform

Roche-assigned fT3/tT3 clinical samples were detected using the T3 Sandwich antibody pair R513c8 (Capture) - R515n5 (Detection) on the Time-resolved Fluorescent Immunoassay (TRFIA) platform. A strong correlation (R² > 0.94) was confirmed between the detection results and Roche-assigned samples.

f/tT3 Sample Coincidence Rate

Concentration (ng/mL)	T value	C value	T/C
0	205	20862	0.0098
0.08	5411	20484	0.2641
0.16	10342	21160	0.4888
0.8	40969	19130	2.1416
4	64041	19371	3.3061
20	84362	21193	3.9807

Table 3. T3 Clinical comparison analysis data on TRFIA

Concentration (ng/mL)	T value	C value	T/C
5	345	22103	0.0156
20	1564	20159	0.0776
100	8298	18947	0.4380
500	31267	21537	1.4518
2000	50473	20476	2.4650

Table 4. T4 Cross reactivity data on TRFIA

Figure 6. fT3 Standard curve on TRFIA

Figure 7. tT3 Standard curve on TRFIA

Clinical Significance

Biological function and diagnostic significance of 3,3',5-Triiodo-L-thyronine (T3)

Guidelines to thyroid disease diagnosis/treatment and summary of professional consensus

3,3',5-Triiodo-L-thyronine (T3) is a kind of hormone and micromolecular hapten secreted by thyroid gland, with a molecular weight of 650. T3 affects almost every physiological process of the body, including body growth, metabolism, body temperature and heart rate. About 80% of T3 in human body is bound to thyroid-binding globulin (TBG), and the rest is bound to thyroxine-binding precursor protein or serum protein. Only about 0.3% of T3 exists in free status (fT3). However, only fT3 has biological activity promoting material metabolism, energy release and body growth.

Thyroid function

3,3',5-Triiodo-L-thyronine (T3) is an important clinical indicator to evaluate thyroid function, which has important clinical significance in the diagnosis and efficacy detection of thyroid disease such as hyperthyroidism and hypothyroidism.
Research indicates that the level of free T3 (fT3) in serum can better reflect the clinical status than the total T3 level (the total T3 level changes with the concentration of carrier protein, while the fT3 level remains relatively constant). The increase of serum T3 concentration is mainly observed in hyperthyroidism. The combined detection of serum fT3 and serum free Thyroid hormones (fT4) can be used in the diagnosis, disease assessment and efficacy monitoring of hyperthyroidism and hypothyroidism.

Cardiovascular diseases

The concentration of serum free triiodothyronine (fT3) can reflect the activity of thyroid hormones. Thyroid function disorders can significantly increase the incidence rate and mortality of cardiovascular diseases. During long-term follow-ups, the incidence rate of cardiovascular diseases in the low fT3 level group was found significantly higher than that in the normal fT3 group, indicating that serum fT3 level is an important influencing factor for cardiovascular diseases, and low fT3 level indicates such risk may take place.

Moreover, the concentration of serum fT3 can directly affect the metabolism of blood lipids and blood glucose, and dyslipidemia can lead to the endothelial dysfunction. Research indicates that among familial hypercholesterolemia patients, the increase of cholesterol can lead to the disorder of endothelial function, which is one of the important mechanisms of early stage atherosclerosis.