Piperlongumine (PL) is a bioactive alkaloid and medicinal compound of piperamide isolated from the long pepper (Piper longum Linn). It has demonstrated bactericidal action against Mycobacterium tuberculosis (MTB), the cause of pulmonary tuberculosis; nevertheless, immunomodulatory activity had not been identified for it in MTB-triggered granulomatous inflammation. This study investigated if piperlongumine could inhibit such inflammation.

Granulocyte-macrophage colony stimulating factor (GM-CSF) and interleukin-4 (IL-4) are cytokines widely used in ex vivo monocyte differentiation experiments, vaccine formulations and disease treatment. The aim of this study was to produce recombinant bovine GM-CSF and IL-4 in an episomal expression system that conserves the postransductional modification of the native proteins and to use the products to differentiate bovine monocytes into dendritic cells.

The role of phospholipase D toxoid (PLD) vaccine in enhancing killing activity of macrophages was demonstrated in this study. Four groups of Balb/c mice were vaccinated with different forms of current vaccines against Corynebacterium pseudotuberculosis (C. pseudotuberculosis). The first group was vaccinated with purified recombinant mutated PLD protein adjuvated vaccine; the second with formalin inactivated whole cells of C. pseudotuberculosis adjuvated vaccine, the third group with combined bacterin-toxoid adjuvated vaccine and the fourth was given viable C. pseudotuberculosis cells. Mononuclear peritoneal cells from each vaccinated groups were collected and inoculated intraperitoneally into naïve recipient Balb/c mice that were subsequently challenged by equal number of live C. pseudotuberculosis cells. Killing activity of peritoneal macrophages collected from each recipient group of mice was assayed by cultivation of lysed macrophages on plates of count brain heart agar. It was reported that the highest killing activity of macrophages were those collected from mice vaccinated with recombinant PLD adjuvated vaccine that reaches 95% of phagocytosed C. pseudotuberculosis living bacteria; where those given viable C. pseudotuberculosis bacteria (80%); then combined vaccine (69.5%) and the least killing activity was performed by macrophages obtained from bacterin vaccinated animals

Macrophages are crucial immune cells that play a role in tissue repair and can exhibit pro- or anti-inflammatory behaviour based on environmental stimulation. Their functional phenotype can be affected by platelet-derived products as determined by those products’ composition. When the inflammatory response caused by implantation is excessive, it can lead to rejection of the implant. Therefore, a thorough evaluation of implant haemocompatibility is necessary to minimise undesirable consequences.