1. The objective of the inflammatory response in the case of injury is to eliminate components of damaged tissue, allowing the body to begin healing. The initial step of this procedure is distinguished by a shift in blood flow in the affected region. Blood vessels dilate and increase blood flow into the tissue over time, causing redness in the damaged region. Following this, blood vessel permeability increases, allowing fluid, proteins, and white blood cells to move from the circulation to the site of tissue injury. Swelling is caused by a surge of fluids, cells, and additional substances to the wounded spot. The activity of white blood cells, particularly phagocytes, reduces swelling, heat, and redness in wounded tissue regions. Phagocytes remove cellular debris left behind from the injury. Neutrophil phagocytes contain digestive enzyme granules specialized for this sort of function. Within an hour after damage, they often invade the area that was impacted in significant numbers. Other white cells known as monocytes enter the region one to two days later to finish the process of cleaning out dead cells. In most cases, an inflammatory reaction caused by an injury lasts only a few days. If the inflammation persists, it may become chronic, with continuous low-level swelling, prolonged tissue damage, and exceptionally slow recovery.
2. Humoral immunity constitutes a facet of specialized immune responses targeting specific antigens. It manifests through distinct antibodies synthesized by B lymphocytes, carefully selected to counteract the specific antigen in focus. The generation of these specific antibodies occurs within lymphoid tissues by activated B lymphocytes, commonly known as plasma cells. Consequently, the decrease in peripheral circulation of B cells in response to stressors, such as during space flight, does not provide a straightforward indication of whether humoral immunity has been suppressed or enhanced. This ambiguity arises because a significant portion of cells may have migrated into lymph nodes, positioning themselves to actively produce antibodies.
References:
Rogers, K. (n.d.). How is inflammation involved in swelling? Encyclopedia Britannica. https://www.britannica.com/story/how-is-inflammation-involved-in-swelling#:~:text=Immediately following an injury%2C the,by damage to living tissues.
Pendl, H., & Tizard, I. R. (2016). Immunology. In Elsevier eBooks (pp. 400–432). https://doi.org/10.1016/b978-1-4557-4671-2.00020-3