抗体依存性感染増強
コロナウイルス感染の場合 > β-コロナウイルス > ADEおよび疾患の発症機序（英語版） > 一次感染 > 抗体を介した、または介さない免疫細胞の感染

SARS-CoV-1：ex vivo の実験で、SARS-CoV-1が初代単球およびマクロファージ内で複製され、不稔感染を引き起こしたり、感染力の低いウイルス力価をもたらしたりする可能性があるという限定的な証拠が存在する。また、Sタンパク質を標的とする抗体が、ex vivo で、単球、B細胞、マクロファージの非生産的なウイルスの不稔感染を促進する可能性があるという証拠も存在している。確立された細胞株と初代ヒトマクロファージは、抗体媒介性の不稔ウイルス感染に対して脆弱である可能性がある。
SARS-CoV-2：ex vivo の実験で、SARS-CoV-2が健康なドナーの末梢血単核球（英語版）（PBMC）から分離された  初代CD4+ T細胞の不稔感染を促進できるという限定的な証拠が存在する。このウイルス複製過程は、抗体の不在下でも進行する。いくつかの予備データは、SARS-CoV-2抗原および複製二本鎖RNA中間体がCOVID-19患者の単球、B細胞、（より頻度は低いが）末梢血単核球由来のCD4+ T細胞で検出されたことを示している。加えてこの研究では、ウイルスはex vivo で健康なドナーの末梢血単核球中で低力価のウイルスを複製できることが示されている。
下表にSARS-CoV-1とSARS-CoV-2による免疫細胞感染の証拠となる論文をまとめる。
| 0 | 1 | 2 | 3 |
| --- | --- | --- | --- |
SARS-CoV-1
| Evidence of viral replication in  immune cells without antibodies | Evidence of viral replication in  immune cells without antibodies | Evidence of viral replication in  immune cells without antibodies | Reference. |
| PBMCs of SARS  patients | Genomic RNA  (+RNA) and replicative intermediates (-RNA) were detected by RT-PCR. | Genomic RNA  (+RNA) and replicative intermediates (-RNA) were detected by RT-PCR. |  |
| Evidence of viral infection of immune cells without antibodies | Evidence of viral infection of immune cells without antibodies | Evidence of viral infection of immune cells without antibodies |  |
| PBMCs of  healthy donors (ex vivo) | Primary monocytes/macrophages | Primary cells from some donors were virus resistant and from others were capable of being infected and produce infectious virions. |  |
| PBMCs of  healthy donors (ex vivo) | Primary monocytes/macrophages | Abortive infection |  |
| PBMCs of  healthy donors (ex vivo) | Immature and mature monocyte-derived dendritic cells | Abortive infection |  |
| PBMCs of  healthy donors (ex vivo) | Monocyte-derived dendritic cells | Low infectious titer of produced virions |  |
| Evidence of antibodies mediated non-productive infection of immune cells | Evidence of antibodies mediated non-productive infection of immune cells | Evidence of antibodies mediated non-productive infection of immune cells |  |
| PBMCs of healthy donors (ex vivo) | Primary monocytes/macrophages | Antibodies  targeting S-protein can promote non-productive viral infection. |  |
| Cell line | Monocyte/macrophage cell line (THP-1) | Antibodies  targeting S-protein can promote non-productive viral infection. |  |
| Cell line | B-cell lines (Raji, Daudi) | Antibodies  targeting S-protein can promote non-productive viral infection. |  |
SARS-CoV-2
| Evidence of viral replication in immune cells without antibodies | Evidence of viral replication in immune cells without antibodies | Evidence of viral replication in immune cells without antibodies |  |
| PBMCs of  COVID-19 patients (ex vivo) | Some traces  of viral RNA are present in PBMCs | Some traces  of viral RNA are present in PBMCs |  |
| PBMCs of  COVID-19 patients (ex vivo) | B-cells, monocytes, CD4+ T-cells | Double stranded viral RNA replication intermediates can be detected |  |
| Evidence of viral infection of immune cells without antibodies | Evidence of viral infection of immune cells without antibodies | Evidence of viral infection of immune cells without antibodies |  |
| PBMCs of healthy donors (ex vivo) | Primary CD4+ T-cells | Non-productive  infection |  |
| PBMCs of healthy donors (ex vivo) | B-cells, monocytes and T-cells | Productive infection with low virus titer |  |
| Evidence of viral infection of immune cells in vivo | Evidence of viral infection of immune cells in vivo | Evidence of viral infection of immune cells in vivo |  |
| PBMCs of COVID-19 patients (in vivo) | B-cells, monocytes, CD4+ T-cells | Positive staining for SARS-CoV-2 antigens and double stranded viral RNA |  |