This TNF-α enzyme linked immunosorbent assay (ELISA) applies a technique called a quantitative sandwich immunoassay. The microtiter plate provided in this kit has been pre-coated with a monoclonal antibody specific to TNF-α. Standards or samples are then added to the appropriate microtiter plate wells with a biotin-conjugated monoclonal antibody preparation specific for TNF-α and incubated. TNF-α, if present, will bind and become immobilized by the antibody pre-coated on the wells and then be “sandwiched” by biotin conjugate. The microtiter plate wells are thoroughly washed to remove unbound TNF-α and other components of the sample. In order to quantify the amount of TNF-α present in the sample, Avidin conjugated to Horseradish Peroxidase (HRP) is added to each microplate well and incubated. Avidin is a tetramer containing four identical subunits that each has a high affinity-binding site for biotin. The wells are thoroughly washed to remove all unbound HRP-conjugated Avidin and a TMB (3,3'5,5' tetramethyl-enzidine) substrate solution is added to each well. The enzyme (HRP) and substrate are allowed to react over a short incubation period. Only those wells that contain TNF-α, biotin conjugated antibody, and enzyme-conjugated Avidin will exhibit a change in colour. The enzyme-substrate reaction is terminated by the addition of a sulphuric acid solution and the colour change is measured spectrophotometrically at a wavelength of 450 nm ± 2 nm.

In order to measure the concentration of TNF-α in the samples, this kit includes two calibration diluents (Calibrator Diluent I for serum/plasma testing and Calibrator Diluent II for cell culture supernatant testing.) According to the testing system, the provided standard is diluted (2-fold) with the appropriate Calibrator Diluent and assayed at the same time as the samples. This allows the operator to produce a standard curve of Optical Density (O.D) versus TNF-α concentration (pg/mL). The concentration of TNF-α in the samples is then determined by comparing the O.D. of the samples to the standard curve.

Platform

Microplate

Detection Type

Colorimetric

Sample Type

Serum, plasma, cell culture supernatant, and other biological fluids.

Sensitivity

< 4 pg/ml

Product Range

4-2000 pg/ml

Assay Time

2h 30m - 3h

Specificity

This sandwich ELISA recognises both natural and recombinant human TNF-α.

Reactivity

Human

Cross Reactivity

This assay has shown no cross-reactivity with other cytokines tested.

Storage

Store at 2-8°C.

Synonyms

APC1, APC1 protein, Cachectin, DIF, Differentiation inducing factor, Macrophage cytotoxic factor, soluble form, Tnf, TNF a, TNF alpha, TNF macrophage derived, TNF monocyte derived, TNF superfamily member 2 , TNF superfamily, member 2, TNF, macrophage derived, TNF, monocyte derived, TNF-a, TNF-alpha, TNFA, TNFA_HUMAN, TNFSF2, Tumor necrosis factor, Tumor necrosis factor (TNF superfamily member 2) , Tumor necrosis factor ligand superfamily member 2, Tumor Necrosis Factor, Membrane Form, Tumor necrosis factor, soluble form

Disclaimer

This product is for research use only. It is not intended for diagnostic or therapeutic use.

Scientific Validation Data (1)

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Figure 1: Standard Curve - Human Tumor Necrosis Factor alpha ELISA Kit (A33004)

Representative Standard Curve using Human Tumor Necrosis Factor alpha ELISA Kit (EL10019).

Citations (3)

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Breast-feeding protects infantile diarrhea caused by intestinal protozoan infections.

References: Human Tumor Necrosis Factor alpha ELISA Kit (A33004)

Abstract:

This study investigated the effect of breast-feeding in protection against protozoan infection in infants with persistent diarrhea. Infants were classified into 2 groups; 161 breast-fed infants and the same number of non-breast-fed infants. Microscopic examinations of stool were done for detection of parasites and measuring the intensity of infection. Moreover, serum levels of IgE and TNF-α were measured by ELISA. Cryptosporidium spp., Entamoeba histolytica/Entamoeba dispar, Giardia lamblia, and Blastocystis sp. were demonstrated in infants with persistent diarrhea. The percentage of protozoan infections was significantly lower in breast-fed infants than that in the non-breast-fed infants. The levels of IgE and TNF-α were significantly lower in the breast-fed group than in the non-breast-fed group. There were significant positive associations between the serum levels of IgE and TNF-α and the intensity of parasite infection in the breast-fed group. It is suggested that breast-feeding has an attenuating effect on the rate and intensity of parasite infection.

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Effects of rosiglitazone treatment on insulin resistance and TNF-alpha levels in patients with chronic kidney disease: a prospective study.

References: Human Tumor Necrosis Factor alpha ELISA Kit (A33004)

Abstract:

AIM:

The aim of the study was to investigate the effects of rosiglitazone treatment on insulin resistance (IR) and tumor necrosis factor-alpha (TNF-alpha) levels in non-diabetic chronic kidney disease (CKD) patients with IR.

PATIENTS AND METHODS:

Thirty non-diabetic CKD patients with IR were enrolled in the study. Patients were grouped into two: group 1 (n = 15) received rosiglitazone 4 mg tablet for 3 months and patients who did not receive rosiglitazone treatment constituted the group 2 (n = 15). Baseline and after rosiglitazone treatment, homeostatis model assessment-insulin resistance (HOMA-IR) and TNF-alpha levels were measured.

RESULTS:

There were no statistical differences in gender, age, HOMA-IR and TNF-alpha levels among group 1 and group 2 (p > 0.05 for all). Compared to baseline in group 1, significant differences were found in HOMA-IR and TNF-alpha levels after 3 months (p = 0.023; p = 0.001, respectively).

CONCLUSIONS:

Our study indicates that, rosiglitazone treatment improves the IR and decreases TNF-alpha levels in non-diabetic patients CKD with IR.

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