{"id":210158,"date":"2025-04-30T05:45:22","date_gmt":"2025-04-30T05:45:22","guid":{"rendered":"https:\/\/learnexams.com\/blog\/?p=210158"},"modified":"2025-04-30T05:45:25","modified_gmt":"2025-04-30T05:45:25","slug":"which-of-the-following-immune-cells-molecules-are-most-effective-at-destroying-intracellular-pathogens-2","status":"publish","type":"post","link":"https:\/\/www.learnexams.com\/blog\/2025\/04\/30\/which-of-the-following-immune-cells-molecules-are-most-effective-at-destroying-intracellular-pathogens-2\/","title":{"rendered":"Which of the following immune cells\/molecules are most effective at destroying intracellular pathogens"},"content":{"rendered":"\n<p>Which of the following immune cells\/molecules are most effective at destroying intracellular pathogens?<\/p>\n\n\n\n<p>a. T helper cells<br>b. B cells<br>c. Antibodies<br>d. Complement<br>e. T cytolytic cells<\/p>\n\n\n\n<p><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-ast-global-color-6-color\"><strong>The correct answer and explanation is :<\/strong><\/mark><\/p>\n\n\n\n<p><strong>Correct Answer: e. T cytolytic cells<\/strong><\/p>\n\n\n\n<p><strong>Explanation:<\/strong><\/p>\n\n\n\n<p>Intracellular pathogens\u2014such as viruses, some bacteria (e.g., <em>Mycobacterium tuberculosis<\/em>), and certain protozoa\u2014reside and replicate within host cells, making them largely inaccessible to components of the immune system that target extracellular threats. Among the immune cells and molecules listed, <strong>T cytolytic cells<\/strong> (also called <strong>cytotoxic T lymphocytes<\/strong> or <strong>CD8+ T cells<\/strong>) are the most effective at <strong>detecting and eliminating infected cells<\/strong> that harbor these intracellular pathogens.<\/p>\n\n\n\n<p>T cytolytic cells recognize infected cells by detecting <strong>peptide fragments of the pathogen<\/strong> that are presented on <strong>MHC class I molecules<\/strong> on the surface of all nucleated cells. Once recognition occurs, these T cells are activated and induce <strong>apoptosis (programmed cell death)<\/strong> in the infected cells. They release <strong>perforin<\/strong>, which forms pores in the target cell membrane, and <strong>granzymes<\/strong>, which enter the cell and trigger the apoptotic cascade, effectively destroying the pathogen\u2019s intracellular niche.<\/p>\n\n\n\n<p>Here\u2019s why the other options are less effective against intracellular pathogens:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>a. T helper cells (CD4+ T cells)<\/strong>: These cells are crucial for orchestrating immune responses and activating other cells (like B cells and macrophages), but they do not directly kill infected cells.<\/li>\n\n\n\n<li><strong>b. B cells<\/strong>: These produce antibodies, which mainly target extracellular pathogens. They are not directly involved in killing infected host cells.<\/li>\n\n\n\n<li><strong>c. Antibodies<\/strong>: Although antibodies can neutralize viruses before they enter cells or tag infected cells for destruction, they cannot access pathogens inside cells directly.<\/li>\n\n\n\n<li><strong>d. Complement system<\/strong>: This is part of the innate immune system and works mainly in the extracellular environment, lysing pathogens or tagging them for phagocytosis, but it is ineffective against intracellular organisms.<\/li>\n<\/ul>\n\n\n\n<p>Thus, <strong>T cytolytic cells (CD8+ T cells)<\/strong> are the primary effectors against <strong>intracellular infections<\/strong>, making option <strong>(e)<\/strong> the correct choice.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Which of the following immune cells\/molecules are most effective at destroying intracellular pathogens? a. T helper cellsb. B cellsc. Antibodiesd. Complemente. T cytolytic cells The correct answer and explanation is : Correct Answer: e. T cytolytic cells Explanation: Intracellular pathogens\u2014such as viruses, some bacteria (e.g., Mycobacterium tuberculosis), and certain protozoa\u2014reside and replicate within host cells, [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"site-sidebar-layout":"default","site-content-layout":"","ast-site-content-layout":"default","site-content-style":"default","site-sidebar-style":"default","ast-global-header-display":"","ast-banner-title-visibility":"","ast-main-header-display":"","ast-hfb-above-header-display":"","ast-hfb-below-header-display":"","ast-hfb-mobile-header-display":"","site-post-title":"","ast-breadcrumbs-content":"","ast-featured-img":"","footer-sml-layout":"","ast-disable-related-posts":"","theme-transparent-header-meta":"","adv-header-id-meta":"","stick-header-meta":"","header-above-stick-meta":"","header-main-stick-meta":"","header-below-stick-meta":"","astra-migrate-meta-layouts":"default","ast-page-background-enabled":"default","ast-page-background-meta":{"desktop":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"ast-content-background-meta":{"desktop":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"footnotes":""},"categories":[25],"tags":[],"class_list":["post-210158","post","type-post","status-publish","format-standard","hentry","category-exams-certification"],"_links":{"self":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/210158","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/comments?post=210158"}],"version-history":[{"count":0,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/210158\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/media?parent=210158"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/categories?post=210158"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/tags?post=210158"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}