Gujjarlapudi Deepika, Mittal Ankit, Talukdar Rupjyoti, Banerjee Rupa, Yelamanchili Sadhana, Jagtap Nitin, Raju Vidyavathi Devi Gajapathi, Namburu Veeraiah, Duvvur Nageshwar Reddy
Department of Biochemistry, Asian Institute of Gastroenterology, Gachibowli, Hyderabad, Telangana, India.
Department of Infectious Diseases, Asian Institute of Gastroenterology, Gachibowli, Hyderabad, Telangana, India.
J Family Med Prim Care. 2025 Jul;14(7):2885-2891. doi: 10.4103/jfmpc.jfmpc_1977_24. Epub 2025 Jul 21.
The COVID-19 pandemic's global impact was mitigated through rapid vaccine development, leading to a mix of natural and vaccination-derived immunity. The immunological profile in hybrid immunity remains less studied, especially in regions where non-mRNA vaccines were used. This study focuses on the immunological profiles and predictors of immune response in one such population.
This cohort study assessed their humoral and cellular immune responses, breakthrough Omicron infections, and hospitalization rates based on vaccination and infection history. Immunological assays to measure anti-spike protein and neutralizing antibodies and interferon-γ release assay were performed. Regression models were used to estimate predictors of immune response and hospitalization in patients with breakthrough infections.
The study revealed significant differences in immune response among participants based on their hybrid immunity status, vaccination, and infection history. Higher antibody titers and cellular responses were observed in individuals with hybrid immunity, especially those with dual pre-Omicron and Omicron infections (3326 BAU/ml, IQR: 770.25-5678.25 and 4.92 IU of IFN-γ/mL, respectively, < 0.001). Age, hypertension, baseline antibody levels, and vaccination status were found to predict humoral response. Baseline antibody levels were found to be predictive of hospitalization, and no participants with an antibody titer >250 BAU/mL required hospitalization.
Hybrid immunity is linked to a stronger humoral and cellular immune response, and elevated antibody titers can serve as a surrogate marker for protection against hospitalization. These findings highlight the need to prioritize high-risk groups, such as older adults and individuals with comorbidities, for booster vaccinations to strengthen community-level defenses against COVID-19.
通过快速的疫苗研发，新冠疫情的全球影响得到了缓解，从而产生了自然免疫和疫苗接种衍生免疫的混合状态。混合免疫中的免疫特征仍研究较少，尤其是在使用非信使核糖核酸（mRNA）疫苗的地区。本研究聚焦于这样一群人的免疫特征及免疫反应预测因素。
这项队列研究根据疫苗接种和感染史评估了他们的体液免疫和细胞免疫反应、突破性奥密克戎感染情况及住院率。进行了测量抗刺突蛋白和中和抗体的免疫测定以及干扰素-γ释放测定。采用回归模型来估计突破性感染患者免疫反应和住院情况的预测因素。
该研究揭示了参与者之间基于其混合免疫状态、疫苗接种和感染史的免疫反应存在显著差异。在具有混合免疫的个体中观察到更高的抗体滴度和细胞反应，尤其是那些在奥密克戎毒株出现之前和之后均感染过的个体（分别为3326 BAU/ml，四分位距：770.25 - 5678.25和4.92 IU的干扰素-γ/mL，<0.001）。发现年龄、高血压、基线抗体水平和疫苗接种状态可预测体液反应。发现基线抗体水平可预测住院情况，且抗体滴度>250 BAU/mL的参与者均无需住院。
混合免疫与更强的体液免疫和细胞免疫反应相关，且升高的抗体滴度可作为预防住院的替代标志物。这些发现凸显了对老年人和合并症患者等高风险群体优先进行加强接种以强化社区层面新冠疫情防御的必要性。
