Isolation and characterization of mouse nasal-associated lymphoid tissue

Area of Science:

• Immunology
• Respiratory Tract Research
• Mucosal Immunity

Background:

• Nasal-associated lymphoid tissue (NALT) is a key component of the respiratory tract's mucosal immune system in rodents.
• Understanding NALT's cellular dynamics is crucial for studying upper respiratory tract infections and immune responses.

Purpose of the Study:

• To develop and validate a method for isolating mouse NALT.
• To characterize the cellular composition of NALT in normal and influenza-infected mice.
• To assess the utility of isolated NALT for immunological investigations.

Main Methods:

• Surgical isolation of paired NALT from the palate of mouse upper jaws.
• Flow cytometry (FACScan) analysis of lymphocyte populations (T-cells, B-cells, CD4+, CD8+).
• Culture of NALT lymphocytes to assess cytokine production (IFN-gamma) and antibody secretion (IgA, IgG) post-influenza infection.

Main Results:

• A reproducible method for NALT isolation yielding approximately 3 x 10^5 lymphocytes per fragment.
• NALT lymphocytes in normal mice comprise roughly equal numbers of T- and B-cells, with a CD4+ to CD8+ ratio of 4:1.
• Influenza infection led to a 2-3 fold increase in NALT T- and B-cells, accompanied by increased IFN-gamma production and influenza-specific IgA/IgG antibody secretion.

Conclusions:

• The developed NALT isolation method is effective for immunological studies.
• NALT plays a significant role in the adaptive immune response to respiratory viral infections.
• This method facilitates research into the cellular dynamics of mucosal immunology in the upper respiratory tract.