Interleukin 8 Association with respiratory syncytial virus bronchiolitis: a systematic review and meta-analysis.

Infants with the respiratory syncytial virus (RSV) and human rhinovirus respiratory infection (HRV) produce inflammatory interleukins (ILs) in the respiratory epithelium. The aim of this study was to evaluate the levels of interleukin-8 in RSV negative and RSV positive patients. This study search was conducted without a time limit until 2020 through the databases of PubMed, Wiley, Springer, ScienceDirect and Google Scholar search engines, by two researchers independently. The random-effects model was used to compare of interleukin-8 in RSV negative vs. RSV positive patients, using Revman software version 5 meta-analysis software. Totally, 921 patients were evaluated (207 RSV-negative and 714 RSV-positive). The mean concentration of IL8 in RSV positive patients was 15.02 pg/ml (95% CI: 13.68- 16.35%).  According to the meta-analysis results, the standardized mean difference (SMD) of IL8 concentration between RSV-positive and negative patients was 6.31 pg/ml) (95% confidence interval: 2.50- 10.13%). subtotal analysis of the IL8 laboratory assessment method revealed that there was no significant SMD deference in the studies that have used chemiluminescence (P=0.21). while IL8 concentrations were significantly higher in RSV positives in ELISA and Magnetic bead-based assays (P<0.05).  It appears that RSV positive patients may have greater levels of IL8 than RSV negative ones; whereas the synthesis of IL8 tends to be more secreted into the nasopharyngeal space; whereas the evaluation approach can also affect the results.

Reconstituting National Institute for Biological Standards and Control (NIBSC) chemokines.

We observed significant discrepancies between immunoassay results when using different internally prepared reference preparations for interleukin-8 (IL-8) and monocyte chemoattractant protein-1 (MCP-1) from the National Institute for Biological Standards and Control (NIBSC). To evaluate the reasons for this we prepared the chemokines using diluents that incorporated protein at different steps. This showed that even brief addition of water to these preparations, in the absence of additional protein, resulted in loss of immunoreactivity in assays. The data obtained emphasise the importance of adding protein at an early stage of preparation to avoid loss of material and potential loss of activity.

Serum and urine levels of interleukin-8 in patients with non-Hodgkin's lymphoma.

Angiogenesis plays an important role in many types of cancer. Interleukin-8 (IL-8) is known to be a pro-inflammatory and pro-angiogenic cytokine, and IL-8 has been reported to be associated with tumor progression, prognosis and survival in several types of cancers. However, the role of IL-8 in non-Hodgkin's lymphoma (NHL) has not been fully determined. Here, we evaluated the usefulness of measuring serum and urine IL-8 levels in patients with NHL. We developed reference intervals for serum and urine IL-8 level in 131 control individuals. We measured serum IL-8 and urine IL-8 levels in patients with NHL, and we compared the concentrations with those of control individuals. The reference intervals for serum IL-8 and urine IL-8 corrected by creatinine (Cr) were 15.9-430.3 pg/mL and 0.0-28.4 pg/mg Cr, respectively. The concentrations of urine IL-8/Cr were significantly higher in patients than in controls (48.9+/-194.4 vs. 5.2+/-13.8 pg/mg Cr, P<0.001). However, there were no significant differences in serum IL-8 concentrations between NHL patients and controls (159.2+/-40.4 vs. 99.6+/-107.1 pg/mL; P=0.099). Receiver operating characteristic (ROC) analysis gave 0.83 and 0.43 ROC area values for urine IL-8/Cr and serum IL-8, respectively. There was no correlation between the serum and urine concentrations of IL-8 and clinical variables, the only exception being the international prognostic index (IPI), which showed a marginal correlation with urine IL-8/Cr levels (P=0.07). This study indicated that urine IL-8/Cr levels might be useful as a diagnostic marker of NHL.

Spectroscopic characterization of chemokines: relevance for quality control and standardization.

Chemokines are mediators of inflammation and trafficking of cells of the immune system including a pivotal role in the recruitment and activation of leukocytes. Due to their involvement in a variety of disease processes, chemokines are potential therapeutic targets. The use of chemokines as pharmaceuticals will require that the folded state and the association properties of the protein are well characterized. In this report, we describe the utility of nuclear magnetic resonance spectroscopy as a tool to study these aspects of chemokine structural properties.

Cytokine and growth factor standardization: the need for research to answer modern issues.

New and novel cytokines are being discovered, cloned and entered into clinical trials at such a rate that often the biological activities of these proteins are poorly understood during their development as therapeutic agents. When estimating the biological activity of different preparations with different specific activities by bioassay, mass units cannot be used. Biological activity is therefore expressed as "biological potency units". Due to the pleiotropic nature of cytokine activity, the biological unit requires definition by a standard that is assay-independent. The need to investigate the biological activity of any proposed standard material in a variety of assays, with statistically valid numbers of participants and with appropriate scientific rationale, has led to the design of international collaborative studies that have provided extremely useful data about the biological activity of cytokines. Such information has had a great impact on the choice of material to serve as a standard and has prevented the establishment of inappropriate preparations. Over the years, WHO international standards have been used to reduce the variation in estimates of cytokine preparations within and between laboratories for both immunoassays and bioassays.

Implications for the assay and biological activity of interleukin-8: results of a WHO international collaborative study.

Eight ampouled preparations of interleukin-8 (IL-8) have been evaluated for their suitability to serve as an international standard for IL-8 by 30 laboratories in 12 countries in an international collaborative study. The preparations were assayed in a wide range of in vitro bioassays and immunoassays. It is clear from the study that different recombinant preparations of IL-8 can have different biological specific activities, even though all were produced using E. coli. It is of interest that the intra-laboratory variability of estimates provided by several neutrophil degranulation bioassays was less than that of the immunoassays, suggesting that these bioassays can be as precise, if not more so, than immunoassays. In addition, immunoassay estimates of IL-8 preparations differed from those of bioassays, illustrating the fact that immunoassays do not necessarily measure biologically active cytokine. The large reduction in the inter-laboratory variability of estimates in terms of a common reference preparation clearly illustrates the need for a standard for IL-8. On the basis of the results reported here, with the agreement of the participants of the study and with the authorisation of the Expert Committee on Biological Standardization (ECBS) of the World Health Organization (WHO) the preparation of IL-8 (89/520) was established as the International Standard for IL-8 with an assigned unitage of 1000 IU/ampoule.