Domain: Healthcare — Pathophysiology
Target concept: Viral Hepatitis

Video generation prompt: Two adjacent liver tissue sections from a patient with viral hepatitis are placed on the experimental table -- one stained with HE, the other with immunohistochemical staining for hepatitis B surface antigen (HBsAg) -- and observed under a light microscope.

Evaluation guide:
(i) Target concept: Immunohistochemical detection of HBsAg in hepatocytes is spatially associated with HE-visualized cytopathic changes in viral hepatitis, without a strict one-to-one correspondence at the single-cell level.
Minimum mechanism: Hepatocytes must express HBsAg protein during active HBV infection; DAB chromogen yields brown precipitate upon antibody binding on the IHC section (counterstained with hematoxylin only); on the adjacent HE section, hematoxylin binds DNA (nuclei) and eosin binds cytoplasmic proteins -- this differential affinity enables morphologic assessment of hepatocyte injury for comparison against the IHC section.
(ii)Storyline: [0-2s] Two adjacent glass slides mounted with liver tissue sections from the same biopsy -- one HE-stained, one HBsAg-immunostained -- appear side by side, centered on the table; [2-4s] Light microscope is brought into frame and positioned beside the slides; [4-6s] Microscope eyepiece view fades in on the HE slide's low-power field, confirming tissue location; [6-8s] View zooms to medium power on the HE slide, revealing hepatocyte cords with nuclear hyperchromasia and cytoplasmic ballooning; [8-10s] View shifts to the matching region of the adjacent HBsAg slide, showing brown HBsAg granules concentrated within hepatocyte cytoplasm in the same general area -- mostly overlapping with, though not perfectly matched cell-for-cell to, the region of hepatocyte injury seen on the HE slide. Perspective remains fixed overhead/table-level throughout; no camera movement beyond controlled zoom/fade; all transitions are continuous, non-teleporting, and maintain strict spatial adjacency.

Manual:
Experimental Procedure
1. Prepare two adjacent serial sections from the same liver biopsy: one stained with HE, the other with immunohistochemical staining for HBsAg (hematoxylin counterstain plus DAB chromogen).
2. Mount both slides side by side on the experimental table.
3. Position light microscope adjacent to the slides with objective aligned, examining the HE slide first and then the matching region of the HBsAg slide.
Observation of Experimental Phenomena
- HE slide: hepatocyte nuclei purple/blue, cytoplasm pink; viral hepatitis features include ballooned hepatocytes, acidophilic (Councilman) bodies, and portal lymphocytic infiltrate.
- HBsAg slide: discrete brown granules concentrated in hepatocyte cytoplasm within the same general region as the HE slide's injured hepatocytes; ground-glass hepatocytes bearing abundant HBsAg typically show their own distinctive granular, glassy cytoplasm instead of ballooning or acidophilic change, and cells undergoing apoptosis (Councilman bodies) frequently lose antigen positivity.
Summary of Experimental Principles
Viral hepatitis causes hepatocyte injury; HBsAg accumulates intracellularly in infected hepatocytes (including morphologically distinct ground-glass cells) and is detected via immunohistochemistry on a serial section; comparing this section to an adjacent HE-stained section shows that antigen expression and histopathological injury are spatially associated within affected liver lobules, without a strict one-to-one correspondence at the single-cell level.

Prompt Grounding rubric:
level_1: Neither slide nor microscope appears; no liver tissue section is shown; no staining (HE or HBsAg) is visible anywhere; no experimental table is shown; none of the core objects -- tissue sections, glass slides, microscope -- appear at all.
level_2: At least one core object appears (for example a tissue section, or a microscope, or a glass slide) but they are not properly assembled -- a tissue is unstained or unmounted, the microscope is empty or facing away from the slides, or the slide(s) show no recognizable staining; nothing is placed on a table.
level_3: Two glass slides with mounted liver tissue sit side by side on the experimental table, with a light microscope positioned nearby; one slide reads as HE-stained (visible pink/purple tones) and the other reads as HBsAg-immunostained (visible brown tones present somewhere on it).
level_4: Everything required for score 3 is shown, and in addition: the two slides are clearly identifiable as a matched HE slide and an HBsAg slide from the same specimen; the HE slide shows the full pink-purple hematoxylin-eosin palette somewhere on the tissue, and the HBsAg slide shows brown DAB granules somewhere on its tissue; the microscope's eyepiece/objective is aligned toward the slides rather than pointed away.
level_5: Everything required for score 4 is shown, and in addition: the microscope is shown actively examining the slides -- an eyepiece view or inset is displayed showing tissue at higher magnification; the HE eyepiece view shows the pink-purple palette clearly across the visible field, and the HBsAg eyepiece view (from the adjacent slide) shows brown granules clearly across its visible field; both views show liver tissue architecture (hepatocyte cords) rather than an unrelated or blank field.

Scientific and Causal Correctness rubric:
level_1: The HBsAg signal appears in a color other than brown -- blue, green, or red; the HE slide shows no nuclear blue/purple staining or no pink cytoplasmic staining at all; the tissue architecture does not resemble liver (no hepatocyte cords, no recognizable lobular pattern).
level_2: One of the two stains is clearly wrong: either the HE slide lacks any nuclear/cytoplasmic color contrast (looks like one flat color), or the HBsAg slide shows no brown signal at all, or shows it as a diffuse haze rather than discrete granules, or shows it only outside the tissue (in stroma or vessels); the tissue looks like it came from a different organ (for example lung or kidney architecture) rather than liver.
level_3: The HE slide shows purple/blue nuclei and pink cytoplasm, and is recognizably hepatic (cords, sinusoids, a central vein); the HBsAg slide shows discrete brown granules and is recognizably the matching liver region; however, the brown granules are not clearly confined to hepatocyte cytoplasm -- they also appear in inflammatory cells or in the background matrix, rather than mainly inside liver cells.
level_4: The HE slide shows recognizable viral hepatitis features -- ballooned hepatocytes, acidophilic (Councilman) bodies, or portal lymphocytic infiltrate; the HBsAg slide's brown granules sit mainly inside hepatocyte cytoplasm rather than in inflammatory cells or stroma; the region of the HBsAg slide with the most granules corresponds to roughly the same area of the HE slide that shows the ballooned/injured hepatocytes.
level_5: Everything required for score 4 holds, and in addition: the area of densest HBsAg staining and the area of most severe hepatocyte injury on the HE slide clearly overlap in general location, showing that antigen expression and histopathological damage cluster together in the same region of the liver sample -- without requiring every single antigen-positive cell to also show ballooning or acidophilic change, since HBsAg-laden ground-glass hepatocytes typically show their own distinctive granular cytoplasm rather than ballooning, and without requiring every injured cell to retain antigen, since apoptotic cells often lose it.

Spatiotemporal Consistency rubric:
level_1: A slide or the microscope appears in mid-air and then snaps onto the table with no motion in between; the microscope's position jumps between shots; the lighting swings from bright to dark within consecutive frames; either tissue section flips or rotates with no visible motion carrying it there.
level_2: A slide's placement onto the table happens instantly rather than through a visible motion; the eyepiece view cuts in abruptly with no fade or zoom transition; the shadow cast by the microscope or slides points in a different direction from one frame to the next with no change in the light source.
level_3: Both slides and the microscope stay in the same relative spots on the table for the whole clip; the light and the shadows the objects cast keep the same direction and strength throughout; neither slide nor the microscope blinks out of view and comes back; the slides stay flat on the table and the microscope stays upright; if an eyepiece view is shown, it fades or zooms in rather than cutting in abruptly, and keeps a steady focus and orientation once it appears.
level_4: Everything required for score 3 holds, and in addition: any hand or mechanism placing a slide onto the table slows down naturally as it sets the slide down, rather than stopping instantly; the focus knob, if shown turning, turns through a continuous range rather than skipping between focus levels; any eyepiece view's zoom level changes in a way that matches a real magnification change, without the field boundary suddenly resizing.
level_5: Everything required for score 4 holds, and in addition: the distance between the slides and the microscope's objective lens stays constant throughout; the slides' tilt matches what the eyepiece view would show from that angle; if the camera moves at all, every object shifts at a speed and depth consistent with the others; no frame shows trembling, warping, or a mistimed jump in the image.