Objectives: Convalescent plasma (CP) as a passive source of neutralizing antibodies and immunomodulators is a century-old therapeutic option used for the management of viral diseases. We investigated its effectiveness for the treatment of COVID-19. Design: Open-label, parallel-arm, phase II, multicentre, randomized controlled trial. Setting: Thirty-nine public and private hospitals across India. Participants: Hospitalized, moderately ill confirmed COVID-19 patients (PaO2/FiO2: 200-300 or respiratory rate > 24/min and SpO2 ≤ 93% on room air). Intervention: Participants were randomized to either control (best standard of care (BSC)) or intervention (CP + BSC) arm. Two doses of 200 mL CP was transfused 24 hours apart in the intervention arm. Main Outcome Measure: Composite of progression to severe disease (PaO2/FiO2<100) or all-cause mortality at 28 days post-enrolment. Results: Between 22 nd April to 14 th July 2020, 464 participants were enrolled; 235 and 229 in intervention and control arm, respectively. Composite primary outcome was achieved in 44 (18.7%) participants in the intervention arm and 41 (17.9%) in the control arm [aOR: 1.09; 95% CI: 0.67, 1.77]. Mortality was documented in 34 (13.6%) and 31 (14.6%) participants in intervention and control arm, respectively [aOR) 1.06 95% CI: -0.61 to 1.83]. Interpretation: CP was not associated with reduction in mortality or progression to severe COVID-19. This trial has high generalizability and approximates real-life setting of CP therapy in settings with limited laboratory capacity. A priori measurement of neutralizing antibody titres in donors and participants may further clarify the role of CP in management of COVID-19.

SUMMARY Experiments were conducted to investigate the non‐H‐2 genetic effects on experimental autoimmune thyroiditis (EAT). Strains having C3H or BALB backgroud in general produced higher autoimmune responses to mouse thyroglobulin (MTg) than the B10 or A strains. Comparisons of C3H and B10 congenic strains carrying similar H‐2 haplotypes demonstrated that the C3H congenics had significantly higher MTg antibody titres and more severe thyroid damage, even when the strains carry the low responder H‐2 haplotypes. These observations show that non‐H‐2 gene(s) influences EAT, in addition to genes in the MHC.

Background: The ABO and Rhesus (Rh) blood group systems are important for transfusion of blood and its components, organ transplantation, genetic studies and in medico-legal issues. Despite the long list of several other blood groups discovered so far, the knowledge and distribution of ABO and Rh-D blood group are essential for effective management of blood bank inventory. Methods: We retrospectively studied the distribution of ABO and Rh blood group antigens in donors presenting to our tertiary care teaching hospital blood bank in south India during the period January 2007 to August 2014. Blood group was determined by commercially available standard monoclonal antisera by test tube agglutination technique. Results: A total of 49,110 donor samples were tested during the study period for ABO grouping and Rh-D typing. Out of these 96.9% were males. The frequency of O, B, A, AB and Bombay blood groups were 41.7%, 32.2% 20%, 6.1% and 0.03% respectively. Rh (D) positive and negative blood groups were seen in 92.8% and 7.2% respectively. The allele frequencies of the I A , I B and I O alleles were 0.1398, 0.2148 and 0.6454 respectively. In case of Rh-D group, the calculated gene frequencies for I D and I d were 0.7321 and 0.2679 respectively. Conclusion: Knowledge of blood group systems as documented in the present study helps in efficient management of blood bank and transfusion services in emergencies.

Background: All antibodies to red cell antigens, other than naturally occurring anti-A and anti-B are considered unexpected. They can be either alloantibodies or auto antibodies. In pregnant women, these antibodies may cross the placenta and cause haemolytic disease of the foetus and newborn (HDFN). Timely detection of such antibodies in antenatal women is essential for early management of HDFN. Methods: A prospective cross-sectional study was carried out on 2060 multiparous pregnant women attending the Government Maternity Hospital, Tirupati to detect prevalence of unexpected antibodies. The women were grouped and typed for ABO and rhesus (Rh) D antigens by tube method and screened for alloantibodies by column agglutination technology. The medical and detailed obstetric history of these women were reviewed. Results: The overall prevalence of alloantibodies was 1.1%. There was a statistically significant difference between alloimmunization rates in the Rh D-antigen negative and D-antigen positive women (12.8% versus 0.3%). The antibodies detected in this study were, anti-D (63.8%), anti-D+C (13.7%), anti-C, anti-E, anti-M, anti-Le a , and anti-Le b (4.5% each). Anti-D contributed to 77.3% of total alloimmunization in this study. Conclusions:In spite of the introduction of prophylactic Rh-immunoglobulin, anti-D (77.3%) is still a common antibody identified in the antenatal women of our region. In developing countries like India, universal antenatal antibody screening, though desirable may not be justified at present as the cost and infrastructure required would be immense. However, it is necessary to impose properly formulated protocols to screen at least the pregnant women with adverse obstetric history.