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Background and Objectives: Protein abnormalities include monoclonal gammopathies of undetermined significance (MGUS) and malignant lymphoplasmacytic tumors such as multiple myeloma (MM), Waldenström macroglobulinemia, and amyloid light-chain amyloidosis. MGUS prevalence increases with age, especially in individuals over 50. MGUS progresses to various lymphoplasmacytic diseases, including smoldering MM and MM. Almost all blood donors (BDs) are asymptomatic but some of them could present protein abnormalities. Our objective was to assess the prevalence and impact of protein abnormalities and monoclonal gammopathies (MGs) on transfusion safety among BDs in Morocco. Methods: Two hundred eighty-one serum samples were collected from BDs aged over 40 years old. Total serum protein measurement and protein electrophoresis were performed using the Architect ci8200 and Capillarys-2-Piercing automated systems, respectively. Immunofixation was conducted using hydrates. Results: Protein levels ranged between 59 and 87 g/L (average = 71.69 ± 4.96 g/L). Our results showed 195 (69.39%) normal profiles, 6 (2.13%) MGs, 14 (4.98%) heterogeneous restriction of γ-globulins, and 66 other abnormalities (23.48%) regarding the levels of albumin and proteins from alpha and beta fractions. Conclusion: Our preliminary results appeal to blood transfusion professionals regarding ethical considerations and transfusion safety. BDs with abnormal protein levels should benefit systematically from diagnostic tests and therapies.

SARS-CoV-2 has caused a huge pandemic affecting millions of people and resulting innumerous deaths. A better understanding of the correlation between binding antibodies and neutralizing antibodies is necessary to address protective immunity post-infection or vaccination. Here, we investigate the humoral immune response and the seroprevalence of neutralizing antibodies following vaccination with adenovirus-based vector in 177 serum samples. A Microneutralization (MN) assay was used as a reference method to assess whether neutralizing antibody titers correlated with a positive signal in two commercially available serological tests:a rapid lateral flow immune-chromatographic assay (LFIA) and an enzyme-linked Fluorescence Assay (ELFA). Neutralizing antibodies were detected in most serum samples (84%). COVID-19 convalescent individuals showed high antibody titers and significant neutralizing activity. Spearman correlation coefficients between the serological and neutralization results ranged from 0.8 to 0.9, suggesting a moderate to strong correlation between commercial immunoassays test results (LFIA and ELFA) and virus neutralization.

The characterized 10 Streptomyces isolates were previously selected by their abilities to solubilize phosphates. To investigate whether these isolates represent multifaceted plant growth-promoting rhizobacteria (PGPR), their potassium-solubilizing, auxin-producing and inhibitory activities were determined. The 10 Streptomyces spp. yielded a variable biomass in the presence of insoluble orthoclase as the sole potassium (K) source, indicating that they were able to extract different amounts of K from this source for their own growth. Three strains (AZ, AYD and DE2) released soluble K from insoluble orthoclase in large amounts into the culture broth. The production levels ranged from 125.4 mg/L to 216.6 mg/L after 5 days of culture. Only two strains, Streptomyces enissocaesilis (BYC) and S. tunisiensis (AI), released a larger amount of soluble K from orthoclase and yielded much more biomass. This indicated that the rate of K released from this insoluble orthoclase exceeded its consumption rate for bacterial growth and that some strains solubilized K more efficiently than others. The results also suggest that the K solubilization process of AZ, AYD and DE2 strains, the most efficient K-solubilizing strains, involves a slight acidification of the medium. Furthermore, these 10 Streptomyces spp. were able to secrete indole acetic acid (IAA) in broth medium and ranged from 7.9 ± 0.1 µg/mL to 122.3 ± 0.1 µg/mL. The results of the antibiosis test proved the potential of the 10 tested strains to limit the growth of fungi and bacteria. In dual culture, S. bellus (AYD) had highest inhibitory effect against the three identified fungal causal agents of root rot of sugar beet: Fusarium equiseti and two F. fujikuroi at 55, 43 and 36%, respectively. Streptomyces enissocaesilis (BYC), S. bellus (AYD) and S. saprophyticus (DE2) exhibited higher multifaceted PGPR with their potassium-solubilizing, auxin-producing and inhibitory activities, which could be expected to lead to effectiveness in field trials of sugar beet.