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Volume 27, Number 4—April 2021

Difficulties in Differentiating Coronaviruses from Subcellular Structures in Human Tissues by Electron Microscopy

Hannah A. BullockComments to Author , Cynthia S. Goldsmith, Sherif R. Zaki, Roosecelis B. Martines, and Sara E. Miller
Author affiliations: Synergy America, Inc., Atlanta, Georgia, USA (H.A. Bullock); Centers for Disease Control and Prevention, Atlanta (C.S. Goldsmith, S.R. Zaki, R.B. Martines); Duke Medical Center, Durham, North Carolina, USA (S.E. Miller)

Main Article


Structures misidentified as coronavirus particles by transmission electron microscopy in publications, March–November 2020*

Original reference Tissue Structures misidentified as coronavirus (Figure no., panel) Correct identification Response
Yao et al. (1)
Spiked vesicles in the cytoplasm (1, A–C)
Pesaresi et al. (2) Lung Vacuole containing vesicles (1, A, B) MVB NA
Clusters of dark particles some associated with membranes (1, C, D) RER and possibly ribosomes

Clusters of dark particles (2, A, B, E)
Unidentifiable structures

Grimes et al. (3) Lung Vacuole containing vesicles (2, A) MVB NA

Spiked vesicle in cytoplasm (2, B)
Possible CCV

Ackermann et al. (4)
Dark circular structures (3, D)
Unidentifiable structure
Scholkmann et al. (29)
Borczuk et al. (5) Lung Clusters of dark particles associated with membranes (6, E) Vesiculating RER NA

Spiked vesicle in cytoplasm (7, F)

Bradley et al. (6) Lung Collections of vesicles (5, A, D) Unidentifiable structures Dittmayer et al. (30)
Coated vesicles (5, B) CCVs

Vacuole containing vesicles (5, C)

Intestine Circular membranes in cytoplasm (5, E) Unidentifiable structures NA

Extracellular spiked vesicles (5, F)
Unidentifiable structures

Kidney Spiked vesicles within a membrane (5, G) CCVs NA

Membrane bound vesicles (5, H)
Unidentifiable structures

Su et al. (7)
Spiked vesicles in cytoplasm (2, A–D)
Calomeni et al. (24); Miller et al. (27); Roufosse et al. (28)
Kissling et al. (8)
Vacuole containing vesicles (1, E, F)
Calomeni et al. (24); Miller et al. (27); Roufosse et al. (28)
Varga et al. (9)
Circular membrane structures with surrounding black dots (1, A, B)
Vesiculating RER
Goldsmith et al. (26); Roufosse et al. (28)
Farkash et al. (10) Kidney Spiked vesicles in cytoplasm (3, A–C) CCVs Miller et al. (25); Roufosse et al. (28)

Vacuole containing vesicles (3, D)

B. Diao et al., unpub. data,
Spiked vesicles in cytoplasm (3)
Roufosse et al. (28)
Abbate et al. (11)
Spiked vesicle in cytoplasm (1)
Menter et al. (12) Kidney Vacuoles containing vesicles (4, A–C) MVB, NA

Collection of membrane bound particles (4, D)
Unidentifiable structure

Werion et al. (13)
Circular vesicles with internal black dots (3, A–C)
Outside-in RER
Tavazzi et al. (14)
Spiked vesicles in cytoplasm (2, A–F)
Dittmayer et al. (30)
Dolhnikoff et al. (15) Heart Roughly circular black structures (3, A, D) Unidentifiable structures Dittmayer et al. (30)

Clusters of dark particles, some associated with membranes (3, B, C)
RER and clusters of ribosomes

Paniz-Mondolfi et al. (16) Brain Vacuole containing circular particles (3, A, B) Unidentifiable structures NA

Vacuole containing vesicles (1, C, D)

Wang et al. (17)
Circular structures with surrounding black dots (1, M; 2, J)
Vesiculating RER
Qian et al. (18)
Spiked vesicles in cytoplasm (3, A, B)
Colmenero et al. (19)
Spiked vesicle in cytoplasm (4, D)
Hosier et al. (20) Placenta Spiked vesicles in cytoplasm (4, C–F) CCVs NA

Spherical particles (4, G–I)
Unidentifiable structures

Algarroba et al. (21)
Spiked vesicles in cytoplasm (2–6)
Sisman et al. (22) Placenta Vacuole containing circular particles (1, C) Unidentifiable structures NA

*CCV, clathrin or coatomer coated vesicles; MVB, multivesicular body; NA, not applicable; RER, rough endoplasmic reticulum.

Main Article

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Page updated: March 18, 2021
Page reviewed: March 18, 2021
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