Immunologic analysis of blood samples obtained from horses and stored for twenty-four hours.

This research aimed to determine if blood samples from horses, stored in a refrigerator for twenty-four hours, can still provide accurate information regarding immune function. The study also evaluated the effectiveness of a non-radioactive lymphocyte proliferation assay.

Methodology

• A total of 224 blood samples were collected from 28 clinically normal adult horses.
• The collected samples were treated with heparin, a substance that helps prevent clotting and were then divided into two equal parts. One part was refrigerated overnight, mimicking the process of shipping blood samples, while the other was analyzed on the day of collection.
• Lymphocytes, which are a type of white blood cell integral to the immune response, were isolated from the samples and counted using a specialized procedure.
• The viability and function of these cells were evaluated using cytologic examination, flow cytometry, and mitogen-induced proliferation assays. These are common techniques used to analyze different cell properties.
• Lymphocyte proliferation, or the rapid increase in the number of lymphocytes in response to specific triggers, was also assessed using a radioactive thymidine incorporation assay and a nonradioactive lymphocyte proliferation assay.

Results

• The study found that lymphocytes that had been refrigerated for up to twenty-four hours were still suitable for use in immunologic analysis. The researchers determined that these chilled lymphocytes essentially maintained their viability and exhibited no significant changes in their subsets, with the exception of CD8 cells when compared with freshly isolated lymphocytes.
• The research revealed comparable results in mitogen-induced lymphocyte proliferation assays — methods of examining cell growth and function — between the fresh and refrigerated samples.
• The researchers concluded that the nonradioactive lymphocyte proliferation assay proved to be a reliable alternative to the standard radioactive assay generally used for assessing the proliferation of equine lymphocytes.

Conclusion and Clinical Relevance

• The study results suggest that blood samples can be refrigerated and shipped overnight to a laboratory for immunological assessments. The results of these assessments can enhance a clinician’s ability to diagnose and monitor the effectiveness of treatments.

This study is significant because it proves that blood samples from horses can be stored in a refrigerator for up to twenty-four hours without compromising their suitability for immunologic analysis. This enables horse health diagnostics via blood sampling to become more accessible and feasible for remote locations where immediate sample analysis is not possible.