{"id":266338,"date":"2026-08-26T23:07:00","date_gmt":"2026-08-27T02:07:00","guid":{"rendered":"https:\/\/www.em.com.br\/emalta\/?p=266338"},"modified":"2026-08-24T17:11:17","modified_gmt":"2026-08-24T20:11:17","slug":"o-que-significam-as-letras-a-b-ab-e-o-e-os-sinais-positivo-e-negativo-nos-tipos-sanguineos","status":"publish","type":"post","link":"https:\/\/www.em.com.br\/emalta\/2026\/08\/26\/o-que-significam-as-letras-a-b-ab-e-o-e-os-sinais-positivo-e-negativo-nos-tipos-sanguineos\/","title":{"rendered":"O que significam as letras A, B, AB e O e os sinais positivo e negativo nos tipos sangu\u00edneos?"},"content":{"rendered":"\n<p class=\"wp-block-paragraph\">Um resultado como A+, O- ou AB+ re\u00fane duas classifica\u00e7\u00f5es diferentes. Nos <strong>tipos sangu\u00edneos<\/strong>, as letras A, B, AB e O pertencem ao sistema ABO e indicam ant\u00edgenos presentes nas hem\u00e1cias. O sinal positivo ou negativo informa, na classifica\u00e7\u00e3o rotineira, se o ant\u00edgeno RhD est\u00e1 presente.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">O que as letras A, B, AB e O representam nas hem\u00e1cias?<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">As hem\u00e1cias podem apresentar estruturas chamadas ant\u00edgenos em sua superf\u00edcie. No sistema ABO, os principais que definem os quatro grupos s\u00e3o os ant\u00edgenos A e B.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">A <strong><a href=\"https:\/\/hemominas.mg.gov.br\/doacao-e-atendimento-ambulatorial\/hemoterapia\/componentes-e-tipos-sanguineos?format=pdf&amp;tmpl=component\" target=\"_blank\" rel=\"noopener noreferrer\">Funda\u00e7\u00e3o Hemominas<\/a><\/strong> explica que o grupo A expressa ant\u00edgeno A e o grupo B expressa ant\u00edgeno B. AB apresenta os dois. O grupo O n\u00e3o expressa esses ant\u00edgenos espec\u00edficos do sistema ABO.<\/p>\n\n\n<div class=\"wp-block-image\">\n<figure class=\"aligncenter size-large\"><img decoding=\"async\" width=\"1024\" height=\"576\" src=\"https:\/\/www.em.com.br\/emalta\/wp-content\/uploads\/2026\/08\/sangues23-1024x576.jpg\" alt=\"\" class=\"wp-image-266411\" srcset=\"https:\/\/www.em.com.br\/emalta\/wp-content\/uploads\/2026\/08\/sangues23-1024x576.jpg 1024w, https:\/\/www.em.com.br\/emalta\/wp-content\/uploads\/2026\/08\/sangues23-300x169.jpg 300w, https:\/\/www.em.com.br\/emalta\/wp-content\/uploads\/2026\/08\/sangues23-768x432.jpg 768w, https:\/\/www.em.com.br\/emalta\/wp-content\/uploads\/2026\/08\/sangues23-750x422.jpg 750w, https:\/\/www.em.com.br\/emalta\/wp-content\/uploads\/2026\/08\/sangues23-1140x641.jpg 1140w, https:\/\/www.em.com.br\/emalta\/wp-content\/uploads\/2026\/08\/sangues23.jpg 1280w\" sizes=\"(max-width: 1024px) 100vw, 1024px\" \/><figcaption class=\"wp-element-caption\">Os sinais positivo e negativo est\u00e3o relacionados principalmente ao fator Rh<\/figcaption><\/figure>\n<\/div>\n\n\n<h2 class=\"wp-block-heading\">Como cada uma das quatro letras muda o que existe no sangue?<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Al\u00e9m dos ant\u00edgenos na superf\u00edcie das hem\u00e1cias, o plasma costuma apresentar anticorpos naturais contra determinados ant\u00edgenos ABO que a pr\u00f3pria pessoa n\u00e3o possui.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">A combina\u00e7\u00e3o b\u00e1sica fica assim:<\/p>\n\n\n\n<style>\r\n.card-list{\r\n  box-sizing:border-box;\r\n  display:flex;\r\n  flex-direction:column;\r\n  gap:10px;\r\n  width:100%;\r\n  max-width:680px;\r\n  margin:16px auto;\r\n  font-family:Arial,'Segoe UI',sans-serif;\r\n}\r\n.card-list .item{\r\n  box-sizing:border-box;\r\n  display:grid;\r\n  grid-template-columns:38px minmax(0,1fr);\r\n  gap:11px;\r\n  align-items:start;\r\n  width:100%;\r\n  padding:13px;\r\n  background:#ffffff;\r\n  border:1px solid #e3e7eb;\r\n  border-radius:14px;\r\n  box-shadow:0 3px 10px rgba(0,0,0,.045);\r\n}\r\n.card-list .num{\r\n  display:flex;\r\n  align-items:center;\r\n  justify-content:center;\r\n  width:36px;\r\n  height:36px;\r\n  margin:0;\r\n  background:#0050b3;\r\n  color:#ffffff;\r\n  border-radius:10px;\r\n  font-size:13px;\r\n  font-weight:800;\r\n  line-height:1;\r\n}\r\n.card-list .txt{\r\n  display:flex;\r\n  flex-direction:column;\r\n  gap:4px;\r\n  min-width:0;\r\n  padding-top:1px;\r\n}\r\n.card-list .title{\r\n  display:block;\r\n  color:#1d1d1f;\r\n  font-size:14px;\r\n  font-weight:700;\r\n  line-height:1.35;\r\n}\r\n.card-list .desc{\r\n  display:block;\r\n  color:#626a73;\r\n  font-size:12px;\r\n  line-height:1.5;\r\n}\r\n@media(min-width:641px){\r\n  .card-list{\r\n    gap:14px;\r\n    margin:18px auto;\r\n  }\r\n  .card-list .item{\r\n    grid-template-columns:46px minmax(0,1fr);\r\n    gap:14px;\r\n    padding:16px;\r\n    border-radius:18px;\r\n    box-shadow:0 7px 20px rgba(0,0,0,.055);\r\n  }\r\n  .card-list .num{\r\n    width:42px;\r\n    height:42px;\r\n    border-radius:12px;\r\n    font-size:14px;\r\n  }\r\n  .card-list .title{\r\n    font-size:15px;\r\n  }\r\n  .card-list .desc{\r\n    font-size:13px;\r\n  }\r\n}\r\n<\/style>\r\n<div class=\"google-auto-ads-ignore card-list\">\r\n<div class=\"item\"><div class=\"num\">A<\/div><div class=\"txt\"><span class=\"title\">Tipo A<\/span><span class=\"desc\">As hem\u00e1cias apresentam ant\u00edgeno A, enquanto o plasma normalmente possui anticorpos anti-B.<\/span><\/div><\/div>\r\n<div class=\"item\"><div class=\"num\">B<\/div><div class=\"txt\"><span class=\"title\">Tipo B<\/span><span class=\"desc\">As hem\u00e1cias apresentam ant\u00edgeno B e o plasma normalmente possui anticorpos anti-A.<\/span><\/div><\/div>\r\n<div class=\"item\"><div class=\"num\">AB<\/div><div class=\"txt\"><span class=\"title\">Tipo AB<\/span><span class=\"desc\">As hem\u00e1cias apresentam os ant\u00edgenos A e B e n\u00e3o h\u00e1 os anticorpos naturais anti-A e anti-B t\u00edpicos do sistema ABO.<\/span><\/div><\/div>\r\n<div class=\"item\"><div class=\"num\">O<\/div><div class=\"txt\"><span class=\"title\">Tipo O<\/span><span class=\"desc\">As hem\u00e1cias n\u00e3o apresentam ant\u00edgeno A nem B, enquanto o plasma possui anticorpos anti-A e anti-B.<\/span><\/div><\/div>\r\n<\/div>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Leia tamb\u00e9m: <a href=\"https:\/\/www.em.com.br\/emalta\/2026\/08\/23\/o-que-significa-a-inscricao-uv400-encontrada-nas-etiquetas-dos-oculos-de-sol\/\" target=\"_blank\" rel=\"noreferrer noopener\">O que significa a inscri\u00e7\u00e3o UV400 encontrada nas etiquetas dos \u00f3culos de sol?<\/a><\/strong><\/p>\n\n\n\n<h2 class=\"wp-block-heading\">O que os sinais positivo e negativo acrescentam \u00e0 letra?<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">O sinal est\u00e1 ligado \u00e0 classifica\u00e7\u00e3o RhD. Quando as hem\u00e1cias apresentam o ant\u00edgeno D, a pessoa \u00e9 classificada rotineiramente como RhD positivo; quando ele n\u00e3o \u00e9 detectado, a classifica\u00e7\u00e3o \u00e9 RhD negativo.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Essa informa\u00e7\u00e3o \u00e9 independente da letra do sistema ABO.<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>A+ significa grupo A e RhD positivo.<\/li>\n\n\n\n<li>A- significa grupo A e RhD negativo.<\/li>\n\n\n\n<li>O+ significa grupo O e RhD positivo.<\/li>\n\n\n\n<li>AB- significa grupo AB e RhD negativo.<\/li>\n\n\n\n<li>Qualquer uma das quatro letras pode aparecer com positivo ou negativo.<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">O <strong><a href=\"https:\/\/bvsms.saude.gov.br\/bvs\/publicacoes\/imuno_hematologia_laboratorial.pdf\" target=\"_blank\" rel=\"noopener noreferrer\">Minist\u00e9rio da Sa\u00fade<\/a><\/strong> ressalta que a classifica\u00e7\u00e3o rotineira RhD considera presen\u00e7a ou aus\u00eancia do ant\u00edgeno D. O sistema Rh completo \u00e9 mais complexo e possui outros ant\u00edgenos al\u00e9m dele.<\/p>\n\n\n<div class=\"wp-block-image\">\n<figure class=\"aligncenter size-large\"><img decoding=\"async\" width=\"1024\" height=\"576\" src=\"https:\/\/www.em.com.br\/emalta\/wp-content\/uploads\/2026\/08\/sangues34-1-1024x576.jpg\" alt=\"\" class=\"wp-image-266413\" srcset=\"https:\/\/www.em.com.br\/emalta\/wp-content\/uploads\/2026\/08\/sangues34-1-1024x576.jpg 1024w, https:\/\/www.em.com.br\/emalta\/wp-content\/uploads\/2026\/08\/sangues34-1-300x169.jpg 300w, https:\/\/www.em.com.br\/emalta\/wp-content\/uploads\/2026\/08\/sangues34-1-768x432.jpg 768w, https:\/\/www.em.com.br\/emalta\/wp-content\/uploads\/2026\/08\/sangues34-1-750x422.jpg 750w, https:\/\/www.em.com.br\/emalta\/wp-content\/uploads\/2026\/08\/sangues34-1-1140x641.jpg 1140w, https:\/\/www.em.com.br\/emalta\/wp-content\/uploads\/2026\/08\/sangues34-1.jpg 1280w\" sizes=\"(max-width: 1024px) 100vw, 1024px\" \/><figcaption class=\"wp-element-caption\">A combina\u00e7\u00e3o dessas informa\u00e7\u00f5es forma tipos como A positivo, O negativo e AB positivo<\/figcaption><\/figure>\n<\/div>\n\n\n<h2 class=\"wp-block-heading\">Por que essas combina\u00e7\u00f5es s\u00e3o t\u00e3o importantes antes de uma transfus\u00e3o?<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Uma transfus\u00e3o precisa evitar combina\u00e7\u00f5es capazes de provocar rea\u00e7\u00e3o entre anticorpos do receptor e ant\u00edgenos presentes nas hem\u00e1cias transfundidas. ABO e RhD est\u00e3o entre os sistemas de maior import\u00e2ncia nesse processo.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">A leitura b\u00e1sica dos grupos pode ser organizada assim:<\/p>\n\n\n\n<style>\r\n.premium-tbl{\r\n  box-sizing:border-box;\r\n  display:flex;\r\n  flex-direction:column;\r\n  width:100%;\r\n  max-width:720px;\r\n  margin:18px auto;\r\n  font-family:Arial,'Segoe UI',sans-serif;\r\n}\r\n.premium-tbl table{\r\n  display:block !important;\r\n  width:100% !important;\r\n  margin:0 !important;\r\n  border:0 !important;\r\n  border-collapse:collapse !important;\r\n}\r\n.premium-tbl thead{\r\n  display:none !important;\r\n}\r\n.premium-tbl tbody{\r\n  display:flex !important;\r\n  flex-direction:column;\r\n  gap:10px;\r\n  width:100%;\r\n}\r\n.premium-tbl tr{\r\n  box-sizing:border-box;\r\n  display:block !important;\r\n  width:100% !important;\r\n  overflow:hidden;\r\n  background:#ffffff;\r\n  border:1px solid #e2e6ea !important;\r\n  border-radius:14px;\r\n  box-shadow:0 3px 10px rgba(0,0,0,.045);\r\n}\r\n.premium-tbl td{\r\n  box-sizing:border-box !important;\r\n  display:block !important;\r\n  width:100% !important;\r\n  padding:10px 13px !important;\r\n  background:#ffffff !important;\r\n  color:#242424 !important;\r\n  border:0 !important;\r\n  border-bottom:1px solid #edf0f2 !important;\r\n  font-size:13px !important;\r\n  line-height:1.45 !important;\r\n  text-align:left !important;\r\n  vertical-align:top !important;\r\n  overflow-wrap:anywhere;\r\n}\r\n.premium-tbl td:last-child{\r\n  border-bottom:0 !important;\r\n}\r\n.premium-tbl td::before{\r\n  content:attr(data-label);\r\n  display:block;\r\n  margin-bottom:4px;\r\n  color:#7a828c;\r\n  font-size:9px;\r\n  font-weight:800;\r\n  line-height:1.2;\r\n  text-align:left;\r\n  text-transform:uppercase;\r\n  letter-spacing:.045em;\r\n}\r\n.premium-tbl .main{\r\n  display:block;\r\n  margin:0 0 2px;\r\n  color:#1a1a1a;\r\n  font-size:14px;\r\n  font-weight:700;\r\n  line-height:1.3;\r\n  text-align:left;\r\n}\r\n.premium-tbl .sub{\r\n  display:block;\r\n  color:#68717c;\r\n  font-size:11px;\r\n  line-height:1.4;\r\n  text-align:left;\r\n}\r\n.premium-tbl .badge{\r\n  display:inline-flex;\r\n  align-items:center;\r\n  max-width:100%;\r\n  padding:4px 9px;\r\n  border-radius:999px;\r\n  font-size:11px;\r\n  font-weight:700;\r\n  line-height:1.25;\r\n  white-space:normal;\r\n}\r\n.premium-tbl .ok{\r\n  background:#e1f5ee;\r\n  color:#0f6e56;\r\n}\r\n.premium-tbl .alerta{\r\n  background:#faeeda;\r\n  color:#854f0b;\r\n}\r\n.premium-tbl .risco{\r\n  background:#fcebeb;\r\n  color:#a32d2d;\r\n}\r\n.premium-tbl .neutro{\r\n  background:#e6f1fb;\r\n  color:#185fa5;\r\n}\r\n@media(min-width:641px){\r\n  .premium-tbl{\r\n    overflow:hidden;\r\n    background:#ffffff;\r\n    border:1px solid #e2e6ea;\r\n    border-radius:16px;\r\n    box-shadow:0 6px 18px rgba(0,0,0,.06);\r\n  }\r\n  .premium-tbl table{\r\n    display:table !important;\r\n    width:100% !important;\r\n    max-width:none !important;\r\n    min-width:0 !important;\r\n    table-layout:fixed !important;\r\n  }\r\n  .premium-tbl thead{\r\n    display:table-header-group !important;\r\n  }\r\n  .premium-tbl tbody{\r\n    display:table-row-group !important;\r\n  }\r\n  .premium-tbl tr{\r\n    display:table-row !important;\r\n    border:0 !important;\r\n    border-radius:0;\r\n    box-shadow:none;\r\n  }\r\n  .premium-tbl th{\r\n    box-sizing:border-box !important;\r\n    padding:14px 16px !important;\r\n    background:#0050b3 !important;\r\n    color:#ffffff !important;\r\n    border:0 !important;\r\n    font-size:12px !important;\r\n    font-weight:700 !important;\r\n    line-height:1.35 !important;\r\n    text-align:left !important;\r\n    text-transform:uppercase;\r\n    letter-spacing:.03em;\r\n  }\r\n  .premium-tbl td{\r\n    display:table-cell !important;\r\n    width:auto !important;\r\n    padding:14px 16px !important;\r\n    font-size:14px !important;\r\n    line-height:1.45 !important;\r\n    border-bottom:1px solid #e8ebee !important;\r\n  }\r\n  .premium-tbl td::before{\r\n    display:none;\r\n  }\r\n  .premium-tbl tbody tr:nth-child(odd) td{\r\n    background:#fafafa !important;\r\n  }\r\n  .premium-tbl tbody tr:nth-child(even) td{\r\n    background:#ffffff !important;\r\n  }\r\n  .premium-tbl tbody tr:last-child td{\r\n    border-bottom:0 !important;\r\n  }\r\n  .premium-tbl th:nth-child(1),\r\n  .premium-tbl td:nth-child(1){\r\n    width:32% !important;\r\n  }\r\n  .premium-tbl th:nth-child(2),\r\n  .premium-tbl td:nth-child(2){\r\n    width:40% !important;\r\n  }\r\n  .premium-tbl th:nth-child(3),\r\n  .premium-tbl td:nth-child(3){\r\n    width:28% !important;\r\n  }\r\n  .premium-tbl .main{\r\n    font-size:14px;\r\n  }\r\n  .premium-tbl .sub{\r\n    font-size:12px;\r\n  }\r\n  .premium-tbl .badge{\r\n    font-size:12px;\r\n    padding:5px 9px;\r\n  }\r\n}\r\n<\/style>\r\n<div class=\"google-auto-ads-ignore premium-tbl\">\r\n<table>\r\n<thead><tr><th>Grupo<\/th><th>Ant\u00edgenos ABO na hem\u00e1cia<\/th><th>Anticorpos ABO no plasma<\/th><\/tr><\/thead>\r\n<tbody>\r\n<tr><td data-label=\"Grupo\"><span class=\"main\">A<\/span><span class=\"sub\">Sistema ABO<\/span><\/td><td data-label=\"Ant\u00edgenos ABO na hem\u00e1cia\">Ant\u00edgeno A<\/td><td data-label=\"Anticorpos ABO no plasma\"><span class=\"badge neutro\">Anti-B<\/span><\/td><\/tr>\r\n<tr><td data-label=\"Grupo\"><span class=\"main\">B<\/span><span class=\"sub\">Sistema ABO<\/span><\/td><td data-label=\"Ant\u00edgenos ABO na hem\u00e1cia\">Ant\u00edgeno B<\/td><td data-label=\"Anticorpos ABO no plasma\"><span class=\"badge neutro\">Anti-A<\/span><\/td><\/tr>\r\n<tr><td data-label=\"Grupo\"><span class=\"main\">AB<\/span><span class=\"sub\">Sistema ABO<\/span><\/td><td data-label=\"Ant\u00edgenos ABO na hem\u00e1cia\">A e B<\/td><td data-label=\"Anticorpos ABO no plasma\"><span class=\"badge ok\">Sem anti-A e anti-B naturais<\/span><\/td><\/tr>\r\n<tr><td data-label=\"Grupo\"><span class=\"main\">O<\/span><span class=\"sub\">Sistema ABO<\/span><\/td><td data-label=\"Ant\u00edgenos ABO na hem\u00e1cia\">Nem A nem B<\/td><td data-label=\"Anticorpos ABO no plasma\"><span class=\"badge alerta\">Anti-A e anti-B<\/span><\/td><\/tr>\r\n<\/tbody>\r\n<\/table>\r\n<\/div>\n\n\n\n<h2 class=\"wp-block-heading\">ABO e Rh s\u00e3o os \u00fanicos grupos sangu\u00edneos que existem?<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">N\u00e3o. Eles s\u00e3o extremamente importantes na pr\u00e1tica transfusional, mas existem muitos outros sistemas de grupos sangu\u00edneos. Hemominas cita, entre outros, Kidd, Duffy, MNS e Lewis.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Por isso, conhecer apenas que algu\u00e9m \u00e9 O+, A- ou AB+ n\u00e3o substitui os testes feitos antes de uma transfus\u00e3o. Servi\u00e7os de hemoterapia analisam compatibilidade e outros anticorpos relevantes para reduzir o risco de rea\u00e7\u00f5es.<\/p>\n\n\n\n<style>\r\n.curio-box{\r\n  box-sizing:border-box;\r\n  display:flex;\r\n  flex-direction:column;\r\n  gap:6px;\r\n  width:100%;\r\n  max-width:680px;\r\n  margin:20px auto 4px;\r\n  background:#f5f7fa;\r\n  border:1px solid #e5e7eb;\r\n  border-radius:16px;\r\n  padding:16px 18px;\r\n  box-shadow:0 6px 18px rgba(0,0,0,.05);\r\n  font-family:Arial,'Segoe UI',sans-serif;\r\n}\r\n.curio-box .tag{\r\n  display:flex;\r\n  align-items:center;\r\n  gap:6px;\r\n  font-size:11px;\r\n  font-weight:800;\r\n  text-transform:uppercase;\r\n  letter-spacing:.05em;\r\n  color:#2c3e50;\r\n}\r\n.curio-box .txt{\r\n  font-size:13px;\r\n  color:#333;\r\n  line-height:1.6;\r\n}\r\n<\/style>\r\n<div class=\"google-auto-ads-ignore curio-box\">\r\n<span class=\"tag\">\ud83d\udca1 Curiosidade<\/span>\r\n<span class=\"txt\">Karl Landsteiner descreveu os primeiros grupos do sistema ABO em 1900; o grupo AB foi relatado pouco depois, em 1902, completando a classifica\u00e7\u00e3o b\u00e1sica usada at\u00e9 hoje.<\/span>\r\n<\/div>\n","protected":false},"excerpt":{"rendered":"<p>Um resultado como A+, O- ou AB+ re\u00fane duas classifica\u00e7\u00f5es diferentes. Nos tipos sangu\u00edneos, as letras A, B, AB e O pertencem ao sistema ABO e indicam ant\u00edgenos presentes nas hem\u00e1cias. O sinal positivo ou negativo informa, na classifica\u00e7\u00e3o rotineira, se o ant\u00edgeno RhD est\u00e1 presente. O que as letras A, B, AB e O [&hellip;]<\/p>\n","protected":false},"author":30,"featured_media":266410,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"jnews-multi-image_gallery":[],"jnews_single_post":{"format":"standard"},"jnews_primary_category":[],"jnews_social_meta":[],"jnews_override_counter":[],"footnotes":""},"categories":[29],"tags":[36390,36391,9234,36389],"class_list":["post-266338","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-entretenimento","tag-fator-rh","tag-hemoterapia","tag-sangue","tag-sistema-abo"],"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v28.3 - https:\/\/yoast.com\/product\/yoast-seo-wordpress\/ -->\n<title>O que significam as letras A, B, AB e O e os sinais positivo e negativo nos tipos sangu\u00edneos? - Estado de Minas - Em Alta<\/title>\n<meta name=\"description\" content=\"As letras A, B, AB e O indicam ant\u00edgenos do sistema ABO, enquanto os sinais positivo e negativo mostram a presen\u00e7a ou aus\u00eancia do RhD.\" \/>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/www.em.com.br\/emalta\/2026\/08\/26\/o-que-significam-as-letras-a-b-ab-e-o-e-os-sinais-positivo-e-negativo-nos-tipos-sanguineos\/\" \/>\n<meta property=\"og:locale\" content=\"pt_BR\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"O que significam as letras A, B, AB e O e os sinais positivo e negativo nos tipos sangu\u00edneos? - Estado de Minas - Em Alta\" \/>\n<meta property=\"og:description\" content=\"As letras A, B, AB e O indicam ant\u00edgenos do sistema ABO, enquanto os sinais positivo e negativo mostram a presen\u00e7a ou aus\u00eancia do RhD.\" \/>\n<meta property=\"og:url\" content=\"https:\/\/www.em.com.br\/emalta\/2026\/08\/26\/o-que-significam-as-letras-a-b-ab-e-o-e-os-sinais-positivo-e-negativo-nos-tipos-sanguineos\/\" \/>\n<meta property=\"og:site_name\" content=\"Estado de Minas - Em Alta\" \/>\n<meta property=\"article:published_time\" content=\"2026-08-27T02:07:00+00:00\" \/>\n<meta property=\"og:image\" content=\"https:\/\/www.em.com.br\/emalta\/wp-content\/uploads\/2026\/08\/sangues1.jpg\" \/>\n\t<meta property=\"og:image:width\" content=\"1280\" \/>\n\t<meta property=\"og:image:height\" content=\"720\" \/>\n\t<meta property=\"og:image:type\" content=\"image\/jpeg\" \/>\n<meta name=\"author\" content=\"Guilherme Ara\u00fajo\" \/>\n<meta name=\"twitter:card\" content=\"summary_large_image\" \/>\n<meta name=\"twitter:label1\" content=\"Escrito por\" \/>\n\t<meta name=\"twitter:data1\" content=\"Guilherme Ara\u00fajo\" \/>\n\t<meta name=\"twitter:label2\" content=\"Est. tempo de leitura\" \/>\n\t<meta name=\"twitter:data2\" content=\"4 minutos\" \/>\n<!-- \/ Yoast SEO plugin. -->","yoast_head_json":{"title":"O que significam as letras A, B, AB e O e os sinais positivo e negativo nos tipos sangu\u00edneos? 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