HLA-C TYPING

HLA typing detects variations in a person’s human leukocyte antigen genes—cell-surface proteins that help the immune system distinguish self from non‑self. It’s used to match organ and stem‑cell donors and recipients, assess susceptibility to certain autoimmune conditions, predict some drug‑related hypersensitivity reactions (for example, abacavir), and support research and forensic/paternity investigations.

HLA‑C is linked to autoimmune and inflammatory conditions—most strongly psoriasis (especially HLA‑C*06:02) and psoriatic arthritis—and contributes to susceptibility to other spondyloarthropathies. Specific HLA‑C variants also influence antiviral outcomes (HIV, hepatitis C), affect NK‑cell responses via KIR interactions, modulate disease severity and age of onset, and are important for transplant compatibility and immune‑mediated rejection.

The HLA‑C test identifies a person’s HLA‑C gene variants (a class I HLA on chromosome 6). It’s DNA-based typing used for organ and stem-cell donor matching, assessing risk for certain immune-related diseases and pregnancy complications, and guiding clinical decisions. Samples are usually blood or cheek swab, and results specify the individual’s HLA‑C alleles.

HLA-C is a class I human leukocyte antigen that presents intracellular (endogenous) peptide fragments to CD8+ T lymphocytes, enabling detection and killing of virus‑infected or transformed cells. It also binds natural killer (NK) cell receptors (KIRs), delivering inhibitory or activating signals that regulate NK cell cytotoxicity. HLA‑C alleles influence transplant compatibility, immune responses and susceptibility to certain diseases.

A positive HLA test indicates you carry a specific HLA allele linked to certain conditions (e.g., autoimmune disease or transplant compatibility), but it’s not a definitive diagnosis. Clinical correlation, additional tests, and specialist evaluation are usually needed. Results can guide monitoring, screening, treatment decisions, or family counseling. Discuss your specific HLA type and next steps with your healthcare provider.

HLA typing can identify genetic risk factors linked to some autoimmune diseases (for example, HLA‑B27, HLA‑DR4, HLA‑DQ2/DQ8), but it cannot definitively predict who will develop disease. Many people with risk HLA types never get autoimmune illness, and disease can occur without them. HLA results are useful alongside symptoms, antibody tests and clinical evaluation for risk assessment and diagnosis, not as standalone predictors.