Measles (paramyxovirus) inclusion bodies: where are the characteristic inclusions typically found within infected cells?

Introduction / Context:
Inclusion bodies are accumulations of viral components or altered host structures visible under light microscopy with appropriate stains. For measles virus (a member of the Paramyxoviridae family), inclusion bodies help pathologists and virologists recognize infection in tissues and cell culture.

Given Data / Assumptions:

• Measles virus is an enveloped, negative-sense RNA virus.
• Cytopathic effects include multinucleated giant cells (Warthin–Finkeldey cells) and characteristic inclusions.
• Question asks for the location(s) of inclusions.

Concept / Approach:
Measles infection can produce both cytoplasmic and nuclear inclusion bodies. Cytoplasmic inclusions reflect sites of nucleocapsid accumulation and replication complex components; nuclear inclusions can also be observed in infected lymphoid tissues. Recognition of inclusions is part of classic histopathological diagnosis, although modern diagnosis relies on serology and molecular testing.

Step-by-Step Solution:

Verification / Alternative check:
Histology texts describe Warthin–Finkeldey giant cells with both intranuclear and intracytoplasmic inclusions in measles-affected lymphoid tissues.

Why Other Options Are Wrong:

• Intracytoplasmic only or intranuclear only: Each is incomplete for measles, which can display both.
• None of these: Incorrect because inclusions are indeed observed.

Common Pitfalls:
Confusing measles with rabies (Negri bodies are cytoplasmic) or CMV (prominent intranuclear inclusions); assuming a single compartment for all RNA viruses.

Final Answer:
both (a) and (b)