The production of antimicrobial peptides is one of the most evolutionarily ancient mechanisms of defense for multicellular organisms, and most eukaryotic species make many different forms of these proteins. For instance, human paneth cells in the gastrointestinal epithelium make 21 different defensins. The reason for this diversity of antimicrobial peptides is: Epithelial cells make different forms than those made by neutrophils. Neutrophils make many different defensins and store them as inactive proteins in their secretory granules. Most of them are produced only in response to infection. The production of different peptides is induced following a bacterial infection versus a fungal infection. Each one has distinct activities against Gram-negative bacteria, Gram-positive bacteria, or fungi.

Which antibody type description among A- D is falsely characterized? A) O IgA: form dimers; prevent adherence of pathogens to mucosal surfaces 1f1 B) O IgG: circulating antibody with multiple functions; formed in high numbers in secondary antibody response C) O IgM: forms multimers whose function is agglutination of infectious microbes D) O IgE, IgD: carry out their function while bound to the surfaces of specific cell types E) O None are false, A-D are all correct

Please explain why

picture 1 shows the directed migration of two immune cell types, neutrophils (red) and macrophages (green) to a laser-induced injury in the ear of a mouse. As you can observe from the video, there are three stages to this process: 1) an initial phase characterized by fast recruitment of neutrophils (red) to the site of injury followed by 2) the slower recruitment of macrophages after which 3) the interaction between both cell types is stabilized. Recruitment to the injury site is mediated by leukotriene B4 (LTB4), a potent immune signaling molecule (Figure 1A). LTB4 binds to BLT1, a G-protein coupled receptor (GPCR), activating various signaling pathways and resulting in immune cell migration to the site of injury (Figure 1B). With this background information and your knowledge of cell and molecular biology, describe in detail in your own words, as many molecular processes as you can identify that must take place for the cell migration process depicted in the video to be achieved. For…

Based on the figure presented in attachment what is the most likely ligand for TLR-XX? Be as specific as possible, and justify your answer based on these data only. Thanks

All of the following are characteristics of defensins except:     A. There are two classes of defensins   B. They require high ionic strength to become active   C. They have low variability and are highly conserved   D. They have broad antimicrobial properties   E. They lead to ionic burst

2.  https://doi.org/10.1186/s12868-022-00692-1   (link to research) a)   In the immunohistochemistry section of the materials and methods section the authors wrote “The number of positive cells in hotspot areas in ten high power fields (HPFs) in areas of demyelination and plaques in the brain stem were counted using the image analysis software (Lecia Application Suite Version 4.12.0, Welzlar, Germany).”  Why were they looking at demyelination areas for this study? b)   In the effect of mitoxantrone on histopathological changes in the brain section of the results section the authors wrote “Active plaques revealed inflammatory cellular infiltrates with abundant macrophages stuffed with myelin debris, an evidence of ongoing myelin breakdown.”  What does macrophages stuffed with myelin debris have to do with the study?

Immunity has been a major concern globally due to the COVID-19 pandemic. Describe the lymphatic circulation and the different lymphoid organs.

The T-cell receptor gene segments are arranged in a similar pattern to immunoglobulin gene segments and are rearranged by the same enzymes. While B cells and T cells differ markedly in their functions during an immune response, the two lymphocyte subsets share the enzymatic machinery and overall scheme for generating antigen receptor diversity. This is because: B cells and T cells recognize the same form of antigen expressed by an infecting pathogen. Animals with B cells developed first, and later evolving species then developed T cells. B cells and T cells both need enormous antigen receptor diversity to provide protection against the diversity of pathogens. Antibody and T-cell receptor gene segments are both flanked by similar recombination signal sequences. B cells and T cells both secrete their antigen receptor proteins after they are activated by antigen-binding.

Poison oak and poison ivy, which involve a CD8 cell response, are examples of what type of hypersensitivity reaction? O 1) 1 O 2) |I O 3) II O 4) IV