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2.
Blood Adv ; 6(1): 207-211, 2022 01 11.
Article in English | MEDLINE | ID: covidwho-1542102

ABSTRACT

Immunocompromised individuals such as patients with chronic lymphocytic leukemia (CLL) are at risk of impaired immune responses to vaccination. The objective of our study was to evaluate severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-specific antibody responses in patients with CLL after the first, second, and third doses of the BNT162b2 or mRNA-1273 vaccines and after a single dose for patients with confirmed previous COVID-19. In all, 530 patients were included in the study. Patients received 2 doses at a 4-week interval and a third dose if they were seronegative after the second dose. Response rate was 27% after dose 1 and 52% after dose 2. Post-dose 2 treatment-naïve patients had the highest response rate (72%) followed by patients previously treated by chemoimmunotherapy (60%). Among patients receiving therapy, those receiving Bruton tyrosine kinase inhibitor alone (22%) or in combination with anti-CD20 monoclonal antibodies or venetoclax (0%) had the poorer response rate whereas patients who received venetoclax monotherapy achieved a significantly higher response rate (52%). A multivariable analysis identified age older than 65 years, ongoing CLL treatment, and gamma globulin ≤6 g/L as independent predictors of the absence of seroconversion. Post-dose 2 seronegative patients had a global response rate of 35% after dose 3. This study provides an argument for the use of a third dose and for prophylactic SARS-CoV-2 neutralizing monoclonal antibodies.


Subject(s)
COVID-19 , Leukemia, Lymphocytic, Chronic, B-Cell , 2019-nCoV Vaccine mRNA-1273 , Aged , Antibodies, Viral , BNT162 Vaccine , COVID-19 Vaccines , Humans , Leukemia, Lymphocytic, Chronic, B-Cell/drug therapy , RNA, Messenger/genetics , SARS-CoV-2
3.
Front Physiol ; 12: 578708, 2021.
Article in English | MEDLINE | ID: covidwho-1207712

ABSTRACT

Background: A computational proteomic analysis suggested that SARS-CoV-2 might bind to hemoglobin (Hb). The authors hypothesized that this phenomenon could result in a decreased oxygen (O2) binding and lead to hemolytic anemia as well. The aim of this work was to investigate whether the affinity of Hb for O2 was altered during COVID-19. Methods: In this retrospective, observational, single-center study, the blood gas analyses of 100 COVID-19 patients were compared to those of 100 non-COVID-19 patients. Fifty-five patients with carboxyhemoglobin (HbCO) ≥8% and 30 with sickle cell disease (SCD) were also included ("positive controls" with abnormal Hb affinity). P50 was corrected for body temperature, pH, and PCO2. Results: Patients did not differ statistically for age or sex ratio in COVID-19 and non-COVID-19 groups. Median P50 at baseline was 26 mmHg [25.2-26.8] vs. 25.9 mmHg [24-27.3], respectively (p = 0.42). As expected, P50 was 22.5 mmHg [21.6-23.8] in the high HbCO group and 29.3 mmHg [27-31.5] in the SCD group (p < 0.0001). Whatever the disease severity, samples from COVID-19 to non-COVID-19 groups were distributed on the standard O2-Hb dissociation curve. When considering the time-course of P50 between days 1 and 18 in both groups, no significant difference was observed. Median Hb concentration at baseline was 14 g.dl-1 [12.6-15.2] in the COVID-19 group vs. 13.2 g.dl-1 [11.4-14.7] in the non-COVID-19 group (p = 0.006). Among the 24 COVID-19 patients displaying anemia, none of them exhibited obvious biological hemolysis. Conclusion: There was no biological argument to support the hypothesis that SARS-CoV-2 could alter O2 binding to Hb.

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