A two-codon mutant of cholera toxin lacking ADP-ribosylating activity functions as an effective adjuvant for eliciting mucosal and systemic cellular immune responses to peptide antigens

Abstract Vaccination with peptide antigens is an effective strategy against mucosal viral infections. We tested a two-codon mutant of cholera toxin (CT-2*) lacking ADP-ribosylating activity and toxicity as a mucosal adjuvant for T cell epitope peptides for intranasal immunization of mice. Efficient induction of helper and cytotoxic T lymphocyte responses associated with TH1 cytokine production were observed in the systemic and mucosal compartments including nasal, gut, and vaginal associated lymphoid tissues. Single or multiple dosing with the peptide antigen and CT-2* induced strong memory immunity without tolerance. These results demonstrate CT-2* as a suitable mucosal adjuvant for priming antigen-specific cellular immune responses

AN ANTIFUNGAL EXTRACELLULAR ENZYMES FROM MALBRANCHEA CHRYSOSPORIOIDEA

ABSTRACT Extracellular enzymes of Malbranchea chrysosporioidea grown on prawn chitin showed chitinase, glucanase and protease activities in crude enzyme. The effect of the crude chitinolytic enzymes was studied for antifungal activity on the growth of several fungi on liquid and solid medium. Fifty percent growth inhibition was observed in liquid cultures by extracelluar enzymes at a concentration of 97-99 μg of protein for Neurospora crassa, Rhizopus chinensis and Trichoderma viridae and for Aspergillus niger at 122 μg. The growth inhibition was more pronounced at low concentration in liquid than in solid culture. These results demonstrate the utilization of crude enzymes of Malbranchea chrysosporioidea in biocontrol activity and opening new path for biotechnological applications

Sex distribution of bacterial isolates from septic wounds.

<p>Sex distribution of bacterial isolates from septic wounds.</p

Predominant bacterial isolates from septic wound patients.

<p>Predominant bacterial isolates from septic wound patients.</p

Isolation and <i>in vitro</i> evaluation of bacteriophages against MDR-bacterial isolates from septic wound infections

<div><p>Multi-drug resistance has become a major problem for the treatment of pathogenic bacterial infections. The use of bacteriophages is an attractive approach to overcome the problem of drug resistance in several pathogens that cause fatal diseases. Our study aimed to isolate multi drug resistant bacteria from patients with septic wounds and then isolate and apply bacteriophages <i>in vitro</i> as alternative therapeutic agents. Pus samples were aseptically collected from Rajiv Gandhi Institute of Medical Science (RIMS), Kadapa, A.P., and samples were analyzed by gram staining, evaluating morphological characteristics, and biochemical methods. MDR-bacterial strains were collected using the Kirby-Bauer disk diffusion method against a variety of antibiotics. Bacteriophages were collected and tested <i>in vitro</i> for lytic activity against MDR-bacterial isolates. Analysis of the pus swab samples revealed that the most of the isolates detected had <i>Pseudomonas aeruginosa</i> as the predominant bacterium, followed by <i>Staphylococcus aureus</i>, <i>Klebsiella pneumoniae</i> and <i>Escherichia coli</i>. Our results suggested that gram-negative bacteria were more predominant than gram-positive bacteria in septic wounds; most of these isolates were resistant to ampicillin, amoxicillin, penicillin, vancomycin and tetracycline. All the gram-positive isolates (100%) were multi-drug resistant, whereas 86% of the gram-negative isolates had a drug resistant nature. Further bacteriophages isolated from sewage demonstrated perfect lytic activity against the multi-drug resistant bacteria causing septic wounds. <i>In vitro</i> analysis of the isolated bacteriophages demonstrated perfect lysis against the corresponding MDR-bacteria, and these isolated phages may be promising as a first choice for prophylaxis against wound sepsis, Moreover, phage therapy does not enhance multi-drug resistance in bacteria and could work simultaneously on a wide variety of MDR-bacteria when used in a bacteriophage cocktail. Hence, our results suggest that these bacteriophages could be potential therapeutic options for treating septic wounds caused by <i>P</i>. <i>aeruginosa</i>, <i>S</i>. <i>aureus</i>, <i>K</i>. <i>pneumoniae</i> and <i>E</i>. <i>coli</i>.</p></div

Wound type with significant bacterial type.

<p>Wound type with significant bacterial type.</p

Spot assay of lytic phages on the MDR-bacteria from septic wounds.

<p><b>Spot assay of lytic phages on the lawn of MDR-bacterial isolates</b>. A. Spot assay of phage MDR-SA1 on the lawn of multi-drug resistant <i>S</i>. <i>aureus</i>. B. Spot assay of phage MDR-PA4 on the lawn of multi-drug resistant <i>P</i>. <i>aeruginosa</i>. C. Spot assay of phage MDR-KP1 on the lawn of multi-drug resistant <i>K</i>. <i>pneumoniae</i>. D. Spot assay of phage MDR-EC3 on the lawn of multi-drug resistant <i>E</i>. <i>coli</i>.</p

Percentage of multi-drug resistance against a variety of antibiotics in septic wound causing bacteria.

<p>Percentage of multi-drug resistance against a variety of antibiotics in septic wound causing bacteria.</p

Age distribution of patients with significant bacterial growth.

<p>Age distribution of patients with significant bacterial growth.</p