Question 1

Which of the following best explains why rabies virus (RABV) is able to evade the host immune response during early infection?

Accepted Answer

RABV employs multiple molecular strategies to avoid detection, including shielding viral RNA and antagonizing interferon signaling.

Question 2

A mouse infected with SHBRABV survives to day 28 and displays high virus-neutralizing antibody (VNA) titers. Which of the following is most likely to be observed in this mouse's draining lymph node?

Accepted Answer

Active germinal center formation with proliferating B cells and plasma cell differentiation.

Question 3

Which viral protein is primarily responsible for antagonizing type I interferon signaling in rabies virus infection?

Accepted Answer

Phosphoprotein (P)

Question 4

In the context of the mouse experiments, which outcome is most indicative of a 'protective' immune response following SADP.5 infection?

Accepted Answer

High VNA titers, balanced Th1/Th2 cytokine profile, and organized germinal centers.

Question 5

A researcher observes that a group of SHBRABV-infected mice have low or undetectable VNA titers and succumb to infection early. Which of the following best explains this outcome?

Accepted Answer

The virus evaded early immune detection, resulting in delayed or impaired adaptive immune activation.

Question 6

Which of the following cytokine patterns is most likely associated with survival and effective viral control in the mouse rabies model?

Accepted Answer

Balanced Th1/Th2 cytokines (e.g., IL-2, IL-4, IFN-γ, IL-10) and strong antiviral cytokines (e.g., IFN-α, IFN-β).

Question 7

Which experimental approach would best distinguish between immune evasion and immune suppression as mechanisms of rabies pathogenesis?

Accepted Answer

Comparing lymphoid architecture and cytokine profiles in survivors versus non-survivors using immunohistochemistry and multiplex cytokine assays.

Question 8

In the mouse model, which of the following best correlates with lower CNS viral burden?

Accepted Answer

Early and robust VNA titers in serum.

Question 9

Which of the following is a key difference between infection with wild-type (street) rabies virus and attenuated vaccine strains in mice?

Accepted Answer

Attenuated strains induce stronger innate and adaptive immune responses, including germinal center formation.

Question 10

A mouse infected with DogRABV at a high dose survives to day 14 but has only borderline VNA titers. What is the most likely explanation for this observation?

Accepted Answer

The mouse mounted a delayed or suboptimal adaptive immune response, possibly due to viral immune evasion.

Question 11

Which of the following best describes the role of the nucleoprotein (N) in rabies virus immune evasion?

Accepted Answer

It shields viral RNA from recognition by RIG-I–like receptors.

Question 12

Which of the following panels of antibodies would be most appropriate to assess germinal center activity in lymphoid tissues by immunohistochemistry?

Accepted Answer

B220, GL7, PNA, BCL6, Ki67, CD138, IgG, IgM

Question 13

A mouse infected with SHBRABV at a very high dose dies by day 6 and shows no detectable VNA titers. Which of the following is the most likely explanation?

Accepted Answer

The mouse's immune system was overwhelmed before adaptive immunity could develop.

Question 14

Which of the following best describes the expected cytokine profile in SADP.5-infected mice that survive to day 14?

Accepted Answer

Balanced Th1/Th2 cytokines and strong antiviral cytokine signature.

Question 15

Which of the following is the most reliable indicator of successful adaptive immune activation in the context of rabies infection in mice?

Accepted Answer

Detectable and robust VNA titers in serum.

Question 16

Which of the following best explains why post-exposure prophylaxis (PEP) is effective in preventing rabies in humans?

Accepted Answer

PEP provides time for the adaptive immune system to generate VNAs before the virus reaches the CNS.

Question 17

Which of the following experimental findings would most strongly support the hypothesis that immune evasion, rather than immune destruction, is the primary mechanism of rabies pathogenesis?

Accepted Answer

Minimal inflammatory lesions in peripheral tissues despite high CNS viral loads.

Question 18

A mouse infected with SADP.5 at a low dose survives and displays high VNA titers, balanced cytokine profile, and organized germinal centers. What does this outcome suggest about the relationship between viral dose and immune response?

Accepted Answer

Even at low doses, an attenuated strain can elicit a strong and protective immune response.

Question 19

Which of the following best describes the relationship between germinal center (GC) activity and VNA titers in the context of rabies infection?

Accepted Answer

High GC activity correlates with high VNA titers and better survival.

Question 20

Which of the following is the most likely outcome in a mouse infected with SHBRABV that fails to mount a timely adaptive immune response?

Accepted Answer

Early death with high CNS viral burden and minimal VNA titers.

Rabies Virus Infection: Immune Response and Pathogenesis in Mouse Models

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