Bambancin Lambda: Maganin Allurar rigakafi kuma mafi yaduwa?

Binciken bayanan jama'a

Bayanai game da dangin SARS-CoV-2 da ranar da aka ɗauki samfurin daga jerin abubuwan da ake samu daga Chile an samo su daga rukunin Consorcio Genomas CoV2 da ke akwai a https://auspice.cov2.cl/ncov/chile-global. An samo bayanan rigakafin daga bayanan jama'a daga Ma'aikatar Kimiyya, Fasaha, Ilimi da Ƙirƙirar da ake samu a https://github.com/MinCiencia/Datos-COVID19 (Shafi na 83).

Gwajin kamuwa da cuta

Kwayoyin cuta na Pseudotyped dauke da sunadaran SARS-CoV-2 daban-daban an shirya su kamar yadda muka bayyana a baya¹². A taƙaice, an samar da pseudotypes na tushen SARS-CoV-1 a cikin sel HEK2T ta hanyar canza pNL293-ΔEnv-Luc tare da daidaitaccen pCDNA-SARS-CoV-4.3 Spike coding vector a cikin 2:1 molar rabo. Plasmids suna yin codon-ingantacciyar karu wanda ba shi da amino acid 1 na ƙarshe na ƙarshen C-terminal (SΔ19) wanda aka sani don guje wa riƙewa a cikin endoplasmic reticulum.¹² an samo su ta hanyar haɓakar kwayoyin halitta ko mutagenesis da aka tsara ta hanyar yanar gizo (GeneScript) kuma sun ƙunshi sauye-sauye masu zuwa: layi A (jerin magana), layin B (D614G), layin B.1.1.7 (Δ69-70, Δ144, N501Y, A570D, D614G, P681H, T716I, S982A, D1118H), layi na P.1 (L18F, T20N, P26S, D138Y, R190S, K417T, E484K, N501Y, D614G, H655Y,1027G, T37 75- 76, L246Q, F252S, D452G, T490N). Kowane shiri na pseudotype an share shi ta hanyar centrifugation a 614 rpm a dakin da zafin jiki, ƙididdigewa ta amfani da HIV-859 Gag p3,000 Quantikine ELISA Kit (R&D Systems), aliquoted a cikin 1% fetal bovine serum (Sigma-Aldrich) da kuma adana a -24 °C har sai amfani. An yi amfani da nau'i daban-daban na ƙwayoyin cuta na pseudotyped (kamar yadda matakan furotin na HIV-50 p80 suka ƙayyade) don cutar da kwayoyin HEK-ACE1 da 24 hours daga baya, an auna aikin luciferase na wuta ta amfani da Luciferase Assay Reagent (Promega) a cikin Glomax 2 Microplate. luminometer (Promega).

Gwajin Neutralization

An yi gwaje-gwajen kawar da ƙwayoyin cuta na Pseudotyped da gaske kamar yadda muka bayyana a baya¹². A taƙaice, an shirya serial dilutions na samfuran plasma (1: 4 zuwa 1: 8748) a cikin DMEM tare da 10% fetal bovine serum kuma an sanya shi tare da 5 ng na p24 na kowane ƙwayar cuta ta pseudotyped yayin 1h a 37 ° C sannan, 1 × 10⁴ na sel HEK-ACE2 an ƙara su zuwa kowace rijiya. Kwayoyin HEK293T (ba bayyana ACE2) waɗanda aka haɗa tare da ƙwayar cuta ta pseudotyped (lineage A) an yi amfani da su azaman iko mara kyau. An lysed cell 48 hours daga baya, kuma firefly luciferase aiki da aka auna ta amfani da Luciferase Assay Reagent (Promega) a cikin Glomax 96 Microplate luminometer (Promega). An ƙididdige yawan adadin neutralization na kowane dilution kuma an ƙididdige ID50 na kowane samfurin ta amfani da sigar GraphPad Prism 9.0.1.

Nazarin ilimin lissafi

An yi nazarin ƙididdiga ta amfani da sigar software ta GraphPad Prism 9.1.2. Kwatancen rukuni da yawa don kawar da titers antibody (NAbTs) a kan kwamitin SARS-CoV-2 pseudotyped ƙwayoyin cuta da kwatancen martanin NAbs ta hanyar jima'i da matsayin hayaki an yi su ta amfani da gwajin sa hannun Wilcoxon guda biyu. An ƙididdige canjin yanayi azaman bambancin ma'anar ma'anar lissafi a cikin ID₅₀ kamar yadda aka kwatanta da na Wild type pseudotyped virus. An gudanar da nazarin daidaito tsakanin NabTs da shekaru ko BMI ta amfani da gwajin Spearman. An yi gwajin kwatancen ANOVA ta hanya ɗaya da Tukey don ƙididdigar ƙididdiga na kamuwa da cuta. An yi la'akari da ƙimar p ≤0.05 a matsayin mahimmancin ƙididdiga.

Amincewa da dabi'a

Kwamitin da'a na Faculty of Medicine a Universidad de Chile (Ayyukan N° 0361-2021 da N° 096-2020) da Clínica Santa Maria (Project N°132604-21) sun amince da tsarin binciken. Duk masu ba da gudummawa sun sanya hannu kan sanarwar da aka sanar, kuma samfuran su ba a ɓoye sunayensu ba.

Tasirin sauye sauye a cikin bambance -bambancen Lambda akan kamuwa da cuta da kawar da martani na ƙwayoyin cuta

Binciken jeri 3695 daga Chile da aka ajiye a GISAID kamar yadda aka yi a ranar 24 ga Yuni^th 2021 yana nuna bayyanannen rinjaye na bambance-bambancen SARS-CoV-2 Gamma da Lambda yayin lissafin watanni na ƙarshe, tare, don kashi 79% na duk jerin.

Abin sha'awa shine, wannan lokacin yana da babban kamfen na rigakafi wanda kashi 65.6% na mutanen da aka yi niyya (masu shekaru 18 da haihuwa) sun sami cikakken tsarin rigakafin kamar yadda aka yi a ranar 27 ga Yuni.^th 2021

Ganin cewa kashi 78.2% na mutanen da aka yiwa cikakken tsari sun sami rigakafin cutar CoronaVac daga Sinovac Biotech, mun nemi bincikar tasirin maye gurbi da ke cikin bambance-bambancen Lambda akan iyawar rigakafin ƙwayoyin cuta da wannan rigakafin ya haifar.

Don wannan, mun ƙirƙiri ƙwayoyin cuta na tushen SARS-CoV-1 na pseudotyped masu ɗauke da furotin mai kauri daga zuriyar Wuhan-2 (Nau'in daji; layin A), maye gurbi na D1G (jinin B), da Alpha (jinin B). .614), Gamma (tsari P.1.1.7) da kuma Lambda (labari C.1).

A yayin shirye-shiryen ƙwayoyin cuta, mun lura akai-akai cewa ƙwayoyin da suka kamu da kwayar cutar pseudotyped ɗauke da karu na Lambda sun samar da mahimman ƙimar bioluminescence idan aka kwatanta da mutantan D614G ko bambance-bambancen Alpha da Gamma waɗanda ke nuna haɓakar kamuwa da cuta ta hanyar furotin na Lambda.

Hoto 1.Cutar sankara ta hanyar sunadaran karu daban-daban.

(A) Tsarin tsari na furotin mai karu na SARS-CoV-2 da bambance-bambancen da aka yi amfani da su a cikin wannan binciken. Ana nuna zuri'a a cikin baka. RBD, yanki mai ɗaure mai karɓa, CM; cytoplasmic wutsiya.

(B) Titration na pseudotypes na kowane zuriya ta amfani da daidai adadin HIV-1 p24. An auna aikin luciferase na firefly azaman raka'o'in luminescence na dangi (RLU) a sa'o'i 48 bayan kamuwa da cuta. Matsakaicin matsakaici da SD an ƙididdige su daga gwaji mai sau uku na wakilci.

Bayan haka, mun yi amfani da ƙwayoyin cuta na pseudotyped da aka ambata a sama don aiwatar da gwaje-gwajen neutralization ta amfani da samfuran plasma 79 daga ma'aikatan kiwon lafiya masu lafiya daga Universidad de Chile da Clínica Santa María a Santiago, Chile.

Mun cire samfurori 4 saboda ba mu iya ƙididdige adadin ID50 ba. Daga samfuran da aka bincika, 73% sun dace da mata, matsakaicin shekaru 34 shekaru (IQR 29 - 43) da max index (BMI) na 25 (IQR 22.7-27). Kashi 20.5% na mahalarta sun bayyana cewa su ne masu shan taba yayin da lokacin rigakafin ya ƙare. An samo samfurori a cikin tsaka-tsakin kwanaki 95 (IQR 76 - 96) bayan kashi na biyu na maganin CoronaVac

Mun lura cewa neutralization na pseudotyped ƙwayoyin cuta dauke da nau'in furotin na karu ya haifar da dilution na hanawa na 50% (ID).₅₀) Ma'anar INTER na 191.46 (154.9), 227.95% ci,), yayin da 95% ci), 153.92 (115.68 (192.16% ci), 95 (124.73% ci), 86.2 (163.2% ci), 95 (104.57 (75.02%), 134.11 (95 (78.75%), 49.8 (107.6% ci), 95 (614% ci), XNUMX (XNUMX% ci), XNUMX (XNUMX (XNUMX%), XNUMX (XNUMX% ci), XNUMX (XNUMX (XNUMX%), XNUMX (XNUMX% ci), XNUMX (XNUMX% ci), XNUMX (XNUMX% ci), XNUMX (XNUMX (XNUMX%) ) da XNUMX (XNUMX - XNUMX, XNUMX% CI) don ƙwayoyin cuta na pseudotyped ɗauke da furotin mai karu daga mutantan DXNUMXG ko bambance-bambancen Alpha, Gamma da Lambda, bi da bi.

Mun kuma lura cewa ma'anar ma'anar geometric na ID₅₀ titers sun ragu da kashi 3.05 (2.57 - 3.61, 95% CI) don ƙwayar cuta ta pseudotyped ɗauke da ƙaruwar Lambda, 2.33 (1.95 - 2.80, 95% CI) don ƙaruwar Gamma, 2.03 (1.71 - 2.41), 95. don karu na Alpha da 1.37 (1.20 - 1.55, 95% CI) don karu na D614G idan aka kwatanta da nau'in daji.

Ba a sami alaƙa tsakanin jima'i, shekaru, ƙididdiga ta jiki (BMI) ko matsayin hayaki da kawar da titers a cikin ƙungiyar bincikenmu ba.

Hoto 2.Gwajin tsaka-tsaki ta amfani da samfuran plasma daga allurar CoronaVac

(A) Canje-canje a cikin juzu'i na tsaka tsaki na 50% (ID₅₀) a cikin samfuran plasma daga masu karɓar 75 na rigakafin CoronaVac a kan D614G (lineage B), Alpha (jinin B.1.1.7),

Gamma (jinin P.1) da Lambda (jinin C.37) bambance-bambancen idan aka kwatanta da nau'in cutar daji. Ana nuna sakamako azaman bambanci a cikin titers neutralization na samfuran da suka dace. P ƙimar don kwatanta ID₅₀ ana ƙididdige su tare da gwajin sa hannun Wilcoxon.

(B) Filayen akwatin sun nuna tsaka-tsaki da kewayon tsaka-tsaki (IQR) na ID₅₀ ga kowane nau'in kwayar cutar pseudotyped. Ana nuna canje-canjen abubuwa azaman bambancin ma'anar ma'anar lissafi a cikin ID₅₀ kamar yadda aka kwatanta da waɗanda na Wild type pseudotyped virus. An yi nazarin ƙididdiga ta amfani da gwajin sa hannun Wilcoxon-match-pairs.

Tare, bayananmu sun nuna cewa furotin mai karu na sabon nau'in nau'in sha'awa Lambda, wanda ke yaduwa sosai a cikin Chile da ƙasashen Kudancin Amurka, yana ɗaukar maye gurbin da ke ba da ƙarin kamuwa da cuta da ikon tserewa daga kawar da ƙwayoyin cuta da CoronaVac ke haifarwa.