Human TNF-α ELISA Kit

RACTIVITY	Human
SENSITIVITY	<4 pg/mL
ASSAY RANGE	4-2000 pg/mL
REAGENTS PROVIDED	TNF-α MICROTITER PLATE  BIOTIN CONJUGATE  AVIDIN CONJUGATE TNF-α STANDARD  CALIBRATOR DILUENT I  CALIBRATOR DILUENT II  WASH BUFFER (20X/96 wells, 30X/192 wells)  SUBSTRATE A  SUBSTRATE B  STOP SOLUTION

INTENDED USE

This Human TNF-alpha (a) ELISA Kit is to be used for the in vitro quantitative determination of human tumour necrosis factor alpha (TNF-a) concentrations in cell culture supernatant, serum, plasma, and other biological fluids. This kit is intended FOR LABORATORY RESEARCH USE ONLY and not for use in diagnostic or therapeutic procedures.

INTRODUCTION

Tumour Necrosis Factor alpha (TNF-a), also known as cachectin was initially named for its remarkable ability to cause hemorrhagic necrosis of tumours in mice.¹  The TNF-a gene located on chromosome 6 encodes a 233 amino acid (a.a.) prohormone bound to the plasma membrane, with the mature form (157a.a., 17kDa) exposed on the extracellular surface.  Soluble, mature TNF-a is released upon cleavage of the C-terminal.^2,3  The primary source in vivo of TNF-a is thought to be the monocyte/macrophage but various cell types are known to express this cytokine such as lymphocytes, basophils, eosinophils, mast cells, NK cells, T cells, B cells, kerantinocytes, Kupffer cells, astrocytes, and some types of tumours.  TNF-a is produced upon stimulation with cytokines such as IL-1, 1L-2, GM-CSF, TNF-a itself and with bacterial lipopolysaccharide (LPS) which is a potent inducer.⁴ TNF-a once produced and secreted will bind to TNF-a receptors (TNF-a R1, 55 kDa and TNF-a R2, 75 kDa), located on the plasma membrane of most cells throughout the body except the red blood cell.⁵  The two TNF-a receptors deliberate the biological effects of TNF-a.  It has been reported that TNF-a R1 is responsible for mediating LPS toxicity⁶ and cell cytotoxicity⁷ and TNF-a R2 is involved in cellular proliferation.⁸  Various pathological conditions are associated with the production of high levels of TNF-a.  These include septic shock syndrome, cachexia (e.g. HIV, tuberculosis, cancer), autoimmune diseases, hepatitis, leukemia, myocardial ischaemia, organ transplantation rejection, multiple sclerosis, rheumatoid arthritis, and meningococcal septicemia.^4,9,10,11  Many people die annually from a complication of infectious disease called septic shock syndrome which is triggered by TNF-a.  In many cases elevated TNF-a serum levels predict a higher mortality.¹² TNF-a is a pleiotropic cytokine that can induce disease through TNF-a toxicity (tissue injury, catabolic illness, and mediating shock) and improve host defense mechanisms (stimulating inflammation and increasing immune cell function).⁴  In the future, therapies may be developed by blocking TNF-a harmful effects and enhancing TNF-a beneficial effects.

This TNF-a ELISA is a 2.5-3 hour solid phase immunoassay readily applicable to measure TNF-a levels in serum, plasma, cell culture supernatant, and other biological fluids in the range of 0 to 1000 pg/mL.  It showed no cross reactivity with other cytokines tested.  

CITATIONS

1. Wu G et al. The influence of psychological stress on the rat temporomandibular joint with the application of countermeasures. J Surg Res. 2012 Dec;178(2):728-36.

2. Ekhlas Hamed Abdel-Hafeez et al. Breast-Feeding Protects Infantile Diarrhea Caused by Intestinal Protozoan Infections. Korean J. Parasitol. Oct, 2013; 51(5): 519-524.

3. T. BASTURK et al. Effects of rosiglitazone treatment on insulin resistance and TNF-alpha levels in patients with chronic kidney disease: a prospective study. European Review for Medical and Pharmacological Sciences. 2012; 16: 1519-1524.

4. Jiang C, Niu J, Li M, Teng Y, Wang H, Zhang Y.Tumor vasculature-targeted recombinant mutated human TNF-α enhanced the antitumor activity of doxorubicin by increasing tumor vessel permeability in mouse xenograft models. PLoS One 2014; 1(9):e87036.

5. Khan A, Ali Z.Normal Ranges for Acute Phase Reactants (Interleukin-6, Tumour Necrosis Factor-alpha and C-reactive Protein) in Umbilical Cord Blood of Healthy Term Neonates at the Mount Hope Women's Hospital, Trinidad. West Indian Med J 2014; 5(63):465-9.

6. Han X, Tao YL, Deng YP, Yu JW, Cai J, Ren GF, Sun YN, Jiang GJ.Metformin ameliorates insulitis in STZ-induced diabetic mice. PeerJ 2017; (5):e3155.

7. Zhu L, Zhang D, Zhu H, Zhu J, Weng S, Dong L, Liu T, Hu Y, Shen X.Berberine treatment increases Akkermansia in the gut and improves high-fat diet-induced atherosclerosis in Apoe-/- mice. Atherosclerosis 2018; (268):117-126.

8. Guo Y, Shi G, Wan H, Zhou M.Hedgehog signaling regulates the expression levels of inflammatory mediators in cigarette‑induced airway inflammation. Mol Med Rep 2018; 6(17):8557-8563.

9. Stockfelt L, Sallsten G, Almerud P, Basu S, Barregard L.Short-term chamber exposure to low doses of two kinds of wood smoke does not induce systemic inflammation, coagulation or oxidative stress in healthy humans. Inhal Toxicol 2013; 8(25):417-25.

10. Jiang XG, Yang XD, Lv Z, Zhuang PH.Elevated serum levels of TNF-α, IL-8, and ECP can be involved in the development and progression of bronchial asthma. J Asthma. 2018 Feb;55(2):111-118.