ABSTRACT
BACKGROUND: Vulnerable populations, such as hemodialysis (HD) patients and kidney transplant (RTx) recipients, have priority for anti-COVID-19 vaccination, because of their impaired immune status. Here, we investigated the immune response after vaccination with BNT162b2 (two doses plus booster) in HD and RTx patients. METHODS: A prospective, observational study was started in two homogeneous groups of 55 HD and 51 RTx patients previously matched from a cohort of 336 patients. Anti-RBD IgG levels, assayed after the second dose with BNT162b2 mRNA, were used to stratify subjects into quintiles. After the second dose and after booster, anti-RBD and IGRA test were evaluated in RTx and HD, belonging to the first and fifth quintiles. RESULTS: After the second dose of vaccine, the median circulating levels of anti-RBD IgG were significantly higher in HD (1456 AU/mL) compared to RTx (27.30 AU/mL). IGRA test showed significantly higher values in the HD (382 mIU/mL) compared with the RTx (73 mIU/mL). After the booster, humoral response increased significantly in both HD (p = 0.0002) and RTx groups (p = 0.009), whereas the T-cellular immunity remained essentially stable in most patients. In RTx patients with a low humoral response after the second dose, the third dose did not significantly strengthen either humoral or cellular immunity. CONCLUSIONS: For HD and RTx, there is great variability in the humoral response to anti-COVID-19 vaccination, with a stronger response in the HD group. The booster dose was ineffective at reinforcing the humoral and cellular immune response in most RTx patients hyporesponsive to the second dose.
Subject(s)
COVID-19 Vaccines , COVID-19 , Kidney Transplantation , Renal Dialysis , Humans , Antibodies, Viral , BNT162 Vaccine , Immunoglobulin G , Kidney Transplantation/adverse effects , Prospective Studies , Transplant Recipients , Vaccines , COVID-19/prevention & control , COVID-19 Vaccines/adverse effectsABSTRACT
Background: SARS-CoV-2 T-cells are crucial for long-term protection against reinfection. The aim was to demonstrate the Interferon-gamma Release Assay (IGRA) test could be useful for vaccination monitoring. Methods: In a prospective cohort of 98 vaccinated healthcare workers for SARS-CoV-2, we selected 23 people in low-antibodies (Group 1, N = 8), high-antibodies (Group 2, N = 9), and negative control groups (Group 3, N = 6). SARS-CoV-2-specific humoral and cellular responses were analyzed at 8 months after two doses of Pfizer BioNTech, evaluating anti-RBD (Receptor Binding Domain) and RBD-ACE2 (Angiotensin Converting Enzyme-2) blocking antibodies in sera through a Chemiluminescence Immunoassay (CLIA) and T-cells through the IGRA test in heparinized plasma. Moreover, lymphocyte subtyping was executed by a flow cytometer. Statistical analysis was performed. Results: The data confirmed that RBD and RBD-ACE2 blocking ACE2 antibody levels of Group 1 were significantly lower than Group 2; p < 0.001. However, T-cells showed no significant difference between Group 1 and Group 2. Conclusions: This work suggests the need for new strategies for booster doses administration.
ABSTRACT
Tuberculosis (TB) is top infectious disease killer caused by a single organism responsible for 1.5 million deaths in 2018. Both COVID-19 and the pandemic response are risking to affect control measures for TB and continuity of essential services for people affected by this infection in western countries and even more in developing countries. Knowledge about concomitant pulmonary TB and COVID-19 is extremely limited. The double burden of these two diseases can have devastating effects. Here, we describe from both the clinical and the immunological point of view a case of a patient with in vitro immune cell anergy affected by bilateral cavitary pulmonary TB and subsequent COVID-19-associated pneumonia with a worst outcome. COVID-19 can be a precipitating factor in TB respiratory failure and, during ongoing SARS-COV-2 pandemic, clinicians must be aware of this possible co-infection in differential diagnosis of patients with active TB and new or worsening chest imaging.