Histocompatibility & immunogenetics exam prep
1,000+ practice questions across the full blueprint, from HLA nomenclature and molecular typing to crossmatch, transplant, and lab regulation. Each answer comes with a quick summary, a technical breakdown, and the terms worth remembering.
T cell positive selection occurs in which region of the thymus?
Positive selection happens in the thymic cortex; negative selection happens later in the medulla.
Thymocytes enter the thymus as CD4-CD8- double negatives and migrate through the cortex, where they must show at least weak affinity for self-MHC to receive a survival signal. Cells that fail this test (roughly 95%) die by apoptosis. Survivors move to the medulla, where negative selection deletes cells with dangerously high affinity for self-peptide/MHC.
Pick an answer to see the explanation.
What's inside
Work topic by topic through the exam blueprint. Every topic has a 15-question quiz and flashcards. Missed a question? The explanation comes in three levels, so you can skim the idea or go as deep as the exam does.
Randomized exams drawn from the full question bank. Review every miss in one place, and watch your progress bar fill as you work through all of it.
General and advanced review sections for the gaps between quizzes: reagents and QC, result reporting, regulation, UNOS, and more. Written to read like a textbook, not a cram sheet.
See the topic listTopics
Built for technologists and scientists in histocompatibility, molecular, serology, blood bank, and clinical pathology labs. Short, readable sections that build from the immune system up to the bench, useful for ASHI, EFI and other national certifying exams.
Android app and web
HLA365 started as an Android app that works offline, with no account needed. The website brings the same questions and explanations to your laptop, so you can use a big screen at home and your phone on the train.
One purchase covers both. If you already bought the Android app, sign in and your access carries over.
Pricing
Lifetime access
$25one time
Try it free for 3 days first. No subscription, no renewals, and future content updates are included.
Buy lifetime accessSecure checkout. Works on the web and, with the same account, on Android.
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FAQ
It follows the ASHI Certified Histocompatibility Specialist (CHS) blueprint. The material is also useful for EFI accreditation and other national or international histocompatibility certifications.
You get 3 days of full access. After that, a single $25 payment unlocks everything permanently.
Yes. Sign in on the website with your email and your Google Play purchase is recognized, so you won't pay again. If anything doesn't match up, email us and we'll sort it out.
The material is constantly being reviewed and updated. When something is found to be outdated, it is taken out or corrected, and every update is included with your purchase.
The first version of the website keeps your access in sync. Syncing question progress across devices can come later.
Email hla365support@gmail.com, or leave a comment on our Google Play listing.
No. HLA365 is an independent study aid and is not affiliated with or endorsed by ASHI, EFI, or any certifying body.
