Imunski odgovor nosečnice s tvorbo protiteles na okužbo z virusom SARS-CoV-2 in njihovo prehajanje skozi posteljico​​

Druškovič, Mirjam (avtor), Premru Sršen, Tanja (mentor), Ihan, Alojz (komentor)

Izhodišče: Okužba z virusom SARS-CoV-2 sproži proti virusu humoralni imunski odziv s tvorbo specifičnih protiteles IgG in IgA, ki jih lahko preučujemo po de novo okužbi pri necepljenih nosečnicah v njihovi krvi ob porodu, 42 dni po porodu in v popkovnični krvi kot posledici prenosa protiteles skozi posteljico k plodu. Metode: V raziskavo je bilo vključenih 387 preiskovank s potrjeno okužbo s SARS-CoV-2 med nosečnostjo z uporabo RT-PCR. Protitelesa IgG in IgA proti SARS-CoV-2 smo kvantificirali z uporabo metode ELISA ob porodu in 42 dni po porodu v krvi preiskovank ter v popkovnični krvi ob porodu. Povezavo med prisotnostjo in ravnjo protiteles s trajanjem nosečnosti ob okužbi, s časom od okužbe do poroda ter kliničnimi značilnostmi preiskovank smo analizirali z uporabo univariatnih in multivariatnih logističnih in linearnih regresijskih modelov. Rezultati: Povprečno trajanje nosečnosti ob okužbi je bilo 31 4/7 tednov; 88,1 % preiskovank je imelo simptomatski potek covida-19. Protitelesa IgG in IgA so bila ob porodu odkrita pri 45,7 % oz. 58,9 %, 42 dni po porodu pa se je ta delež povečal na 72,7 % oz. 76,8 %. Prisotnost protiteles v krvi preiskovank ob porodu je bila neodvisno povezana s simptomatskim potekom covida-19 (razmerje obetov (RO) 3,13; 95-odstotni interval zaupanja (IZ) 1,47–6,69 za IgG in RO 3,62; 95-odstotni IZ 1,8–7,26 za IgA) in višjim indeksom telesne mase pred zanositvijo (p < 0,05), ne pa s časom od okužbe do poroda ali trajanjem nosečnosti ob okužbi. Prisotnost protiteles 42 dni po porodu je bila močno povezana tudi s prisotnostjo protiteles ob porodu (RO 29,97; 95-odstotni IZ 10,11–88,82 za IgG in RO 13,09; 95-odstotni IZ 6,37–26,9 za IgA) in višjim indeksom telesne mase pred zanositvijo (p < 0,05). Prisotnost protiteles IgG v popkovnični krvi je bila statistično značilno povezana s prisotnostjo protiteles IgG v krvi preiskovank ob porodu (p < 0,001). 78,8 % preiskovank s protitelesi IgG v krvi ob porodu je imelo prisotna protitelesa IgG v popkovnični krvi. Razmerje med ravnjo protiteles IgG v popkovnični krvi in ravnjo protiteles IgG v krvi preiskovank ob porodu (razmerje prenosa) je bilo več kot ena in je bilo pomembno povezano s časom od okužbe do poroda (p < 0,001). Zaključek: Simptomatski potek covida-19 in višji indeks telesne mase pred zanositvijo vplivata na prisotnost protiteles po okužbi z virusom SARS-CoV-2 v nosečnosti. Protitelesa IgG prehajajo skozi posteljico k plodu in dosežejo premo sorazmerni delež v popkovnični krvi z deležem v krvi preiskovank že po desetih dneh od okužbe.

• Jezik: Slovenski jezik
• Ključne besede: okužba, virus SARS-CoV-2, humoralni imunski odziv, protitelesa IgG in IgA, covid-19, nosečnice, prenos protiteles skozi posteljico
• Vrsta gradiva: Doktorsko delo/naloga
• Organizacija: MF - Medicinska fakulteta
• Leto izida: 2026
• PID: 20.500.12556/RUL-181007
• Datum objave v RUL: 22.03.2026

Sekundarni jezik

• Jezik: Angleški jezik
• Naslov: Immune respon​se of a pregnant​ woman with the formation of antibodies to infection with the SARS-CoV-2​ virus and their passage​ through the placenta

Izvleček

Background: Infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) triggers a humoral immune response that leads to the formation of specific immunoglobulin G (IgG) and immunoglobulin A (IgA) antibodies against the virus. The aim of the study was to examine the humoral immune response after de novo SARS-CoV-2 infection in unvaccinated pregnant women by determining the profile of IgG and IgA antibodies in maternal blood at delivery and 42 days after delivery. A further aim was to assess the transplacental transfer of these antibodies to the fetus by measuring their presence in umbilical cord blood. The antibody profiles were analyzed in relation to the interval from infection to delivery, the gestational age at the time of infection, the clinical course of coronavirus disease 2019 (COVID-19), and the clinical characteristics of the pregnant women. Methods: A prospective cohort study was conducted between September 1, 2020 and March 1, 2021 at the Department of Perinatology, Division of Gynecology and Obstetrics, University Medical Center Ljubljana, in collaboration with the Institute of Microbiology and Immunology, Faculty of Medicine,University of Ljubljana. A total of 387 pregnant women with SARS-CoV-2 infection confirmed during pregnancy by real-time reverse transcription polymerase chain reaction (RT-PCR) were included. Clinical data were recorded, including age, body mass index (BMI), smoking status, chronic diseases, gestational age at infection and at delivery, and complications during pregnancy, delivery, and the postpartum period. IgG and IgA antibodies were quantified using enzyme-linked immunosorbent assay (ELISA) in maternal blood samples at delivery and 42 days postpartum, and in umbilical cord blood at delivery. Associations between antibody presence and levels and gestational age at infection, the interval from infection to delivery, and clinical characteristics were analyzed using univariate and multivariate logistic and linear regression models. Results: The mean gestational age at the time of infection was 31 4/7 weeks. Overall, 88.1% of participants had a symptomatic course of COVID-19. IgG and IgA antibodies were detected in 45.7% and 58.9% of participants at delivery, respectively, increasing to 72.7% and 76.8% at 42 days postpartum. The presence of IgG and IgA antibodies in maternal blood at delivery was independently associated with symptomatic COVID-19 (odds ratio [OR] 3.13; 95% confidence interval [CI] 1.47–6.69 and OR 3.62; 95% CI 1.8–7.26), but not with the interval from the positive RT-PCR test to delivery or the gestational age at the positive RT-PCR test. Antibody presence at 42 days postpartum was strongly associated with antibody presence at delivery (OR 29.97; 95% CI 10.11–88.82 for IgG and OR 13.09; 95% CI 6.37–26.9 for IgA). Higher pre-pregnancy BMI was significantly associated with the presence of IgG and IgA antibodies at both delivery and 42 days postpartum (p < 0.05), independent of maternal age and chronic diseases. Participants without chronic diseases had lower antibody levels at delivery, and those with cardiovascular diseases were less likely to have antibodies six weeks after delivery. Smoking significantly reduced the likelihood of having IgG antibodies at delivery. Other clinical parameters did not show a significant association. The presence of IgG antibodies in umbilical cord blood was significantly associated with the presence of IgG antibodies in maternal blood at delivery (p < 0.001). IgG antibodies were present in cord blood in 78.8% of participants with IgG antibodies in maternal blood at delivery. The median ratio of IgG levels in cord blood to maternal blood was 118%. The only factor significantly associated with the cord-to-maternal IgG ratio was the time from infection to delivery (p < 0.001). The transmission ratio (TR) was greater than 1 when at least 10 days had elapsed from infection to delivery. Conclusion: Most pregnant women in this cohort were infected with SARS-CoV-2 during the third trimester. A substantial proportion developed specific IgG and IgA antibodies during pregnancy and in the postpartum period. These humoral responses were significantly associated with a symptomatic course of COVID-19 and a higher pre-pregnancy BMI. IgG crossed the placenta in most women with detectable maternal antibodies at delivery. A significant direct correlation between maternal and umbilical cord blood IgG levels was evident as early as 10 days after infection, suggesting a potential contribution to neonatal immunity and protection against SARS-CoV-2 infection after delivery.

• Ključne besede: infection, SARS-CoV-2, humoral immune response, antibodies, IgG, IgA, COVID-19, pregnancy, transplacental transfer of antibodies