| HLA-SD | human lymphocyte antigen-serologically defined |
|---|---|
| HLT | heart-lung transplantation; human lipotropin; human lymphocyte transformation |
| HoaRhLG | horse anti-rhesus lymphocyte globulin |
| HPL | human parotid lysozyme; human peripheral lymphocyte; human placental lactogen |
| HTLA | high-titer, low acidity; human T-lymphocyte antigen |