**Core Concept**
Acantholytic cells are keratinocytes that have lost their intercellular connections, resulting in their separation from adjacent cells. This phenomenon is characteristic of pemphigus, a group of autoimmune skin disorders. The loss of cell-cell adhesion is due to the presence of autoantibodies against desmoglein 3, a protein that plays a crucial role in maintaining cell-to-cell adhesion in the epidermis.

**Why the Correct Answer is Right**
In pemphigus, the autoantibodies target the desmoglein 3 protein, which disrupts the desmosomal complex and leads to the breakdown of cell-cell adhesion. As a result, keratinocytes become detached from each other, forming acantholytic cells. This process is a hallmark of pemphigus and can be observed in skin biopsy specimens. The acantholytic cells are typically seen in the epidermis, particularly in the suprabasal layer.

**Why Each Wrong Option is Incorrect**

* **Option A:** Pemphigoid is a different autoimmune skin disorder characterized by the presence of autoantibodies against the basement membrane zone, not desmoglein 3. It does not typically show acantholytic cells.
* **Option B:** Eczema or atopic dermatitis is a chronic inflammatory skin condition that can exhibit spongiosis, but it does not typically show acantholytic cells.
* **Option C:** Psoriasis is a chronic inflammatory skin condition characterized by hyperproliferation of keratinocytes, but it does not typically show acantholytic cells.

**Clinical Pearl / High-Yield Fact**
Acantholytic cells are a key diagnostic feature of pemphigus, and their presence can help differentiate this condition from other autoimmune skin disorders. In clinical practice, a skin biopsy showing acantholytic cells can be a crucial finding in the diagnosis of pemphigus.

**Correct Answer: D. Bullous pemphigoid is incorrect. The correct answer is actually "Pemphigus".